cellular-shader/pngwriter/pngwriter.cc

//**********  pngwriter.cc   **********************************************
//  Author:                    Paul Blackburn
//
//  Email:                     individual61@users.sourceforge.net
//
//  Version:                   0.5.4   (19 / II / 2009)
//
//  Description:               Library that allows plotting a 48 bit
//                             PNG image pixel by pixel, which can
//                             then be opened with a graphics program.
//
//  License:                   GNU General Public License
//                             Copyright 2002, 2003, 2004, 2005, 2006, 2007,
//                             2008, 2009 Paul Blackburn
//
//  Website: Main:             http://pngwriter.sourceforge.net/
//           Sourceforge.net:  http://sourceforge.net/projects/pngwriter/
//           Freshmeat.net:    http://freshmeat.net/projects/pngwriter/
//
//  Documentation:             The header file (pngwriter.h) is commented, but for a
//                             quick reference document, and support,
//                             take a look at the website.
//
//*************************************************************************

/*
 *     This program is free software; you can redistribute it and/or modify
 *     it under the terms of the GNU General Public License as published by
 *     the Free Software Foundation; either version 2 of the License, or
 *     (at your option) any later version.
 *
 *     This program is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public License
 *     along with this program; if not, write to the Free Software
 *     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * */

#include "pngwriter.h"

// Default Constructor
////////////////////////////////////////////////////////////////////////////
pngwriter::pngwriter() {

	filename_ = new char[255];
	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_  = new char[255];
	textsoftware_ = new char[255];
	should_free = true;

	strcpy(filename_, "out.png");
	width_ = 250;
	height_ = 250;
	backgroundcolour_ = 65535;
	compressionlevel_ = -2;
	filegamma_ = 0.5;
	transformation_ = 0;

	strcpy(textauthor_, "PNGwriter Author: Paul Blackburn");
	strcpy(textdescription_, "http://pngwriter.sourceforge.net/");
	strcpy(textsoftware_, "PNGwriter: An easy to use graphics library.");
	strcpy(texttitle_, "out.png");

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//graph_[vhhh][6*hhh + i] where i goes from 0 to 5
			tempindex = 6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}

};

//Copy Constructor
//////////////////////////////////////////////////////////////////////////
pngwriter::pngwriter(const pngwriter& rhs) {
	width_ = rhs.width_;
	height_ = rhs.height_;
	backgroundcolour_ = rhs.backgroundcolour_;
	compressionlevel_ = rhs.compressionlevel_;
	filegamma_ = rhs.filegamma_;
	transformation_ = rhs.transformation_;;
	should_free = true;

	filename_ = new char[strlen(rhs.filename_)+1];
	textauthor_ = new char[strlen(rhs.textauthor_)+1];
	textdescription_ = new char[strlen(rhs.textdescription_)+1];
	textsoftware_ = new char[strlen(rhs.textsoftware_)+1];
	texttitle_ = new char[strlen(rhs.texttitle_)+1];

	strcpy(filename_, rhs.filename_);
	strcpy(textauthor_, rhs.textauthor_);
	strcpy(textdescription_, rhs.textdescription_);
	strcpy(textsoftware_,rhs.textsoftware_);
	strcpy(texttitle_, rhs.texttitle_);

	int kkkk;

	bit_depth_ = rhs.bit_depth_;
	colortype_= rhs.colortype_;
	screengamma_ = rhs.screengamma_;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}
	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//   graph_[vhhh][6*hhh + i ] i=0 to 5
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = rhs.graph_[vhhh][tempindex];
			graph_[vhhh][tempindex+1] = rhs.graph_[vhhh][tempindex+1];
			graph_[vhhh][tempindex+2] = rhs.graph_[vhhh][tempindex+2];
			graph_[vhhh][tempindex+3] = rhs.graph_[vhhh][tempindex+3];
			graph_[vhhh][tempindex+4] = rhs.graph_[vhhh][tempindex+4];
			graph_[vhhh][tempindex+5] = rhs.graph_[vhhh][tempindex+5];
		}
	}

};

//Constructor for int colour levels, char * filename
//////////////////////////////////////////////////////////////////////////
pngwriter::pngwriter(int x, int y, int backgroundcolour, char* filename) {
	width_ = x;
	height_ = y;
	backgroundcolour_ = backgroundcolour;
	compressionlevel_ = 1;
	filegamma_ = 0.6;
	transformation_ = 0;
	should_free = true;

	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_ = new char[strlen(filename)+1];
	textsoftware_ = new char[255];
	filename_ = new char[strlen(filename)+1];

	strcpy(textauthor_, "PNGwriter Author: Paul Blackburn");
	strcpy(textdescription_, "http://pngwriter.sourceforge.net/");
	strcpy(textsoftware_, "PNGwriter: An easy to use graphics library.");
	strcpy(texttitle_, filename);
	strcpy(filename_, filename);

	if((width_<0)||(height_<0)) {
		std::cerr << " PNGwriter::pngwriter - ERROR **: Constructor called with negative height or width. Setting width and height to 1." << std::endl;
		width_ = 1;
		height_ = 1;
	}

	if(backgroundcolour_ >65535) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour greater than 65535. Setting to 65535."<<std::endl;
		backgroundcolour_ = 65535;
	}

	if(backgroundcolour_ <0) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour lower than 0. Setting to 0."<<std::endl;
		backgroundcolour_ = 0;
	}

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//graph_[vhhh][6*hhh + i] i = 0  to 5
			tempindex = 6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}

};

pngwriter::pngwriter(int x, int y, unsigned char * data, char const * filename) {
	width_ = x;
	height_ = y;
	compressionlevel_ = -2;
	filegamma_ = 0.6;
	transformation_ = 0;

	should_free = false;

	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_ = new char[strlen(filename)+1];
	textsoftware_ = new char[255];
	filename_ = new char[strlen(filename)+1];

	strcpy(textauthor_, "Joshua Moerman");
	strcpy(textdescription_, "");
	strcpy(textsoftware_, "");
	strcpy(texttitle_, filename);
	strcpy(filename_, filename);

	if((width_<0)||(height_<0)) {
		std::cerr << " PNGwriter::pngwriter - ERROR **: Constructor called with negative height or width. Setting width and height to 1." << std::endl;
		width_ = 1;
		height_ = 1;
	}

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = &data[kkkk*width_*6];
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

};

//Constructor for double levels, char * filename
/////////////////////////////////////////////////////////////////////////
pngwriter::pngwriter(int x, int y, double backgroundcolour, char* filename) {
	width_ = x;
	height_ = y;
	compressionlevel_ = -2;
	filegamma_ = 0.6;
	transformation_ = 0;
	backgroundcolour_ = int(backgroundcolour*65535);
	should_free = true;

	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_ = new char[strlen(filename)+1];
	textsoftware_ = new char[255];
	filename_ = new char[strlen(filename)+1];

	strcpy(textauthor_, "PNGwriter Author: Paul Blackburn");
	strcpy(textdescription_, "http://pngwriter.sourceforge.net/");
	strcpy(textsoftware_, "PNGwriter: An easy to use graphics library.");
	strcpy(texttitle_, filename);
	strcpy(filename_, filename);

	if((width_<0)||(height_<0)) {
		std::cerr << " PNGwriter::pngwriter - ERROR **: Constructor called with negative height or width. Setting width and height to 1." << std::endl;
		width_ = 1;
		height_ = 1;
	}

	if(backgroundcolour_ >65535) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour greater than 1.0. Setting to 1.0."<<std::endl;
		backgroundcolour_ = 65535;
	}

	if(backgroundcolour_ < 0) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour lower than 0.0. Setting to 0.0."<<std::endl;
		backgroundcolour_ = 0;
	}

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			// graph_[vhhh][tempindex + i] where i = 0 to 5
			tempindex = 6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}

};

//Destructor
///////////////////////////////////////
pngwriter::~pngwriter() {
	delete [] filename_;
	delete [] textauthor_;
	delete [] textdescription_;
	delete [] texttitle_;
	delete [] textsoftware_;

	if(should_free){
		for(int jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
		free(graph_);
	}
};

//Constructor for int levels, const char * filename
//////////////////////////////////////////////////////////////
pngwriter::pngwriter(int x, int y, int backgroundcolour, const char* filename) {
	width_ = x;
	height_ = y;
	backgroundcolour_ = backgroundcolour;
	compressionlevel_ = -2;
	filegamma_ = 0.6;
	transformation_ = 0;
	should_free = true;

	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_ = new char[strlen(filename)+1];
	textsoftware_ = new char[255];
	filename_ = new char[strlen(filename)+1];

	strcpy(textauthor_, "PNGwriter Author: Paul Blackburn");
	strcpy(textdescription_, "http://pngwriter.sourceforge.net/");
	strcpy(textsoftware_, "PNGwriter: An easy to use graphics library.");
	strcpy(texttitle_, filename);
	strcpy(filename_, filename);

	if((width_<0)||(height_<0)) {
		std::cerr << " PNGwriter::pngwriter - ERROR **: Constructor called with negative height or width. Setting width and height to 1." << std::endl;
		height_ = 1;
		width_ = 1;
	}

	if(backgroundcolour_ >65535) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour greater than 65535. Setting to 65535."<<std::endl;
		backgroundcolour_ = 65535;
	}

	if(backgroundcolour_ <0) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour lower than 0. Setting to 0."<<std::endl;
		backgroundcolour_ = 0;
	}

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//graph_[vhhh][6*hhh + i] where i = 0 to 5
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}

};

//Constructor for double levels, const char * filename
/////////////////////////////////////////////////////////////////////////
pngwriter::pngwriter(int x, int y, double backgroundcolour, const char* filename) {
	width_ = x;
	height_ = y;
	compressionlevel_ = -2;
	backgroundcolour_ = int(backgroundcolour*65535);
	filegamma_ = 0.6;
	transformation_ = 0;

	textauthor_ = new char[255];
	textdescription_ = new char[255];
	texttitle_ = new char[strlen(filename)+1];
	textsoftware_ = new char[255];
	filename_ = new char[strlen(filename)+1];

	strcpy(textauthor_, "PNGwriter Author: Paul Blackburn");
	strcpy(textdescription_, "http://pngwriter.sourceforge.net/");
	strcpy(textsoftware_, "PNGwriter: An easy to use graphics library.");
	strcpy(texttitle_, filename);
	strcpy(filename_, filename);

	if((width_<0)||(height_<0)) {
		std::cerr << " PNGwriter::pngwriter - ERROR **: Constructor called with negative height or width. Setting width and height to 1." << std::endl;
		width_ = 1;
		height_ = 1;
	}

	if(backgroundcolour_ >65535) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour greater than 65535. Setting to 65535."<<std::endl;
		backgroundcolour_ = 65535;
	}

	if(backgroundcolour_ <0) {
		std::cerr << " PNGwriter::pngwriter - WARNING **: Constructor called with background colour lower than 0. Setting to 0."<<std::endl;
		backgroundcolour_ = 0;
	}

	int kkkk;

	bit_depth_ = 16; //Default bit depth for new images
	colortype_=2;
	screengamma_ = 2.2;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//etc
			tempindex = 6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}

};

// Overloading operator =
/////////////////////////////////////////////////////////
pngwriter& pngwriter::operator = (const pngwriter& rhs) {
	if(this==&rhs) {
		return *this;
	}

	width_ = rhs.width_;
	height_ = rhs.height_;
	backgroundcolour_ = rhs.backgroundcolour_;
	compressionlevel_ = rhs.compressionlevel_;
	filegamma_ = rhs.filegamma_;
	transformation_ = rhs.transformation_;

	filename_ = new char[strlen(rhs.filename_)+1];
	textauthor_ = new char[strlen(rhs.textauthor_)+1];
	textdescription_ = new char[strlen(rhs.textdescription_)+1];
	textsoftware_ = new char[strlen(rhs.textsoftware_)+1];
	texttitle_ = new char[strlen(rhs.texttitle_)+1];

	strcpy(textauthor_, rhs.textauthor_);
	strcpy(textdescription_, rhs.textdescription_);
	strcpy(textsoftware_,rhs.textsoftware_);
	strcpy(texttitle_, rhs.texttitle_);
	strcpy(filename_, rhs.filename_);

	int kkkk;

	bit_depth_ = rhs.bit_depth_;
	colortype_= rhs.colortype_;
	screengamma_ = rhs.screengamma_;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::pngwriter - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = rhs.graph_[vhhh][tempindex];
			graph_[vhhh][tempindex+1] = rhs.graph_[vhhh][tempindex+1];
			graph_[vhhh][tempindex+2] = rhs.graph_[vhhh][tempindex+2];
			graph_[vhhh][tempindex+3] = rhs.graph_[vhhh][tempindex+3];
			graph_[vhhh][tempindex+4] = rhs.graph_[vhhh][tempindex+4];
			graph_[vhhh][tempindex+5] = rhs.graph_[vhhh][tempindex+5];
		}
	}

	return *this;
}

///////////////////////////////////////////////////////////////
void pngwriter::plot(int x, int y, int red, int green, int blue) {
	int tempindex;

	if(red > 65535) {
		red = 65535;
	}
	if(green > 65535) {
		green = 65535;
	}
	if(blue > 65535) {
		blue = 65535;
	}

	if(red < 0) {
		red = 0;
	}
	if(green < 0) {
		green = 0;
	}
	if(blue < 0) {
		blue = 0;
	}

	if((bit_depth_ == 16)) {
		//	if( (height_-y >-1) && (height_-y <height_) && (6*(x-1) >-1) && (6*(x-1)+5<6*width_) )
		if((y<=height_) && (y>0) && (x>0) && (x<=width_)) {
			//graph_[height_-y][6*(x-1) + i] where i goes from 0 to 5
			tempindex= 6*x-6;
			graph_[height_-y][tempindex] = (char) floor(((double)red)/256);
			graph_[height_-y][tempindex+1] = (char)(red%256);
			graph_[height_-y][tempindex+2] = (char) floor(((double)green)/256);
			graph_[height_-y][tempindex+3] = (char)(green%256);
			graph_[height_-y][tempindex+4] = (char) floor(((double)blue)/256);
			graph_[height_-y][tempindex+5] = (char)(blue%256);
		};

		/*
		 if(!( (height_-y >-1) && (height_-y <height_) && (6*(x-1) >-1) && (6*(x-1)+5<6*width_) ))
		 {
		 std::cerr << " PNGwriter::plot-- Plotting out of range! " << y << "   " << x << std::endl;
		 }
		 */
	}

	if((bit_depth_ == 8)) {
		//	 if( (height_-y >-1) && (height_-y <height_) && (3*(x-1) >-1) && (3*(x-1)+5<3*width_) )
		if((y<height_+1) && (y>0) && (x>0) && (x<width_+1)) {
			//	     graph_[height_-y][3*(x-1) + i] where i goes from 0 to 2
			tempindex = 3*x-3;
			graph_[height_-y][tempindex] = (char)(floor(((double)red)/257.0));
			graph_[height_-y][tempindex+1] = (char)(floor(((double)green)/257.0));
			graph_[height_-y][tempindex+2] = (char)(floor(((double)blue)/257.0));

		};

		/*
		 if(!( (height_-y >-1) && (height_-y <height_) && (6*(x-1) >-1) && (6*(x-1)+5<6*width_) ))
		 {
		 std::cerr << " PNGwriter::plot-- Plotting out of range! " << y << "   " << x << std::endl;
		 }
		 */
	}
};

void pngwriter::plot(int x, int y, double red, double green, double blue) {
	this->plot(x,y,int(red*65535),int(green*65535),int(blue*65535));
};

///////////////////////////////////////////////////////////////
int pngwriter::read(int x, int y, int colour) {
	int temp1,temp2;

	if((colour !=1)&&(colour !=2)&&(colour !=3)) {
		std::cerr << " PNGwriter::read - WARNING **: Invalid argument: should be 1, 2 or 3, is " << colour << std::endl;
		return 0;
	}

	if((x>0) && (x <= (this->width_)) && (y>0) && (y <= (this->height_))) {

		if(bit_depth_ == 16) {
			temp2=6*(x-1);
			if(colour == 1) {
				temp1 = (graph_[(height_-y)][temp2])*256 + graph_[height_-y][temp2+1];
				return temp1;
			}

			if(colour == 2) {
				temp1 = (graph_[height_-y][temp2+2])*256 + graph_[height_-y][temp2+3];
				return temp1;
			}

			if(colour == 3) {
				temp1 = (graph_[height_-y][temp2+4])*256 + graph_[height_-y][temp2+5];
				return temp1;
			}
		}

		if(bit_depth_ == 8) {
			temp2=3*(x-1);
			if(colour == 1) {
				temp1 = graph_[height_-y][temp2];
				return temp1*256;
			}

			if(colour == 2) {
				temp1 =  graph_[height_-y][temp2+1];
				return temp1*256;
			}

			if(colour == 3) {
				temp1 =  graph_[height_-y][temp2+2];
				return temp1*256;
			}
		}
	} else {
		return 0;
	}

	std::cerr << " PNGwriter::read - WARNING **: Returning 0 because of bitdepth/colour type mismatch."<< std::endl;
	return 0;
}

///////////////////////////////////////////////////////////////
int pngwriter::read(int xxx, int yyy) {
	int temp1,temp2,temp3,temp4,temp5;

	if(
		(xxx>0) &&
		(xxx <= (this->width_)) &&
		(yyy>0) &&
		(yyy <= (this->height_))
	) {
		if(bit_depth_ == 16) {
			//	temp1 = (graph_[(height_-yyy)][6*(xxx-1)])*256 + graph_[height_-yyy][6*(xxx-1)+1];
			temp5=6*xxx;
			temp1 = (graph_[(height_-yyy)][temp5-6])*256 + graph_[height_-yyy][temp5-5];
			temp2 = (graph_[height_-yyy][temp5-4])*256 + graph_[height_-yyy][temp5-3];
			temp3 = (graph_[height_-yyy][temp5-2])*256 + graph_[height_-yyy][temp5-1];
			temp4 =  int((temp1+temp2+temp3)/3.0);
		} else if(bit_depth_ == 8) {
			//	temp1 = graph_[height_-yyy][3*(xxx-1)];
			temp5 = 3*xxx;
			temp1 = graph_[height_-yyy][temp5-3];
			temp2 =  graph_[height_-yyy][temp5-2];
			temp3 =  graph_[height_-yyy][temp5-1];
			temp4 =  int((temp1+temp2+temp3)/3.0);
		} else {
			std::cerr << " PNGwriter::read - WARNING **: Invalid bit depth! Returning 0 as average value." << std::endl;
			temp4 = 0;
		}

		return temp4;

	} else {
		return 0;
	}
}

/////////////////////////////////////////////////////
double  pngwriter::dread(int x, int y, int colour) {
	return double(this->read(x,y,colour))/65535.0;
}

double  pngwriter::dread(int x, int y) {
	return double(this->read(x,y))/65535.0;
}

///////////////////////////////////////////////////////
void pngwriter::clear() {
	int pen = 0;
	int pencil = 0;
	int tempindex;

	if(bit_depth_==16) {
		for(pen = 0; pen<width_; pen++) {
			for(pencil = 0; pencil<height_; pencil++) {
				tempindex=6*pen;
				graph_[pencil][tempindex] = 0;
				graph_[pencil][tempindex+1] = 0;
				graph_[pencil][tempindex+2] = 0;
				graph_[pencil][tempindex+3] = 0;
				graph_[pencil][tempindex+4] = 0;
				graph_[pencil][tempindex+5] = 0;
			}
		}
	}

	if(bit_depth_==8) {
		for(pen = 0; pen<width_; pen++) {
			for(pencil = 0; pencil<height_; pencil++) {
				tempindex=3*pen;
				graph_[pencil][tempindex] = 0;
				graph_[pencil][tempindex+1] = 0;
				graph_[pencil][tempindex+2] = 0;
			}
		}
	}

};

/////////////////////////////////////////////////////
void pngwriter::pngwriter_rename(char* newname) {
	delete [] filename_;
	delete [] texttitle_;

	filename_ = new char[strlen(newname)+1];
	texttitle_ = new char[strlen(newname)+1];

	strcpy(filename_,newname);
	strcpy(texttitle_,newname);
};

///////////////////////////////////////////////////////
void pngwriter::pngwriter_rename(const char* newname) {
	delete [] filename_;
	delete [] texttitle_;

	filename_ = new char[strlen(newname)+1];
	texttitle_ = new char[strlen(newname)+1];

	strcpy(filename_,newname);
	strcpy(texttitle_,newname);
};

///////////////////////////////////////////////////////
void pngwriter::pngwriter_rename(long unsigned int index) {
	char buffer[255];

	//   %[flags][width][.precision][modifiers]type
	//
	if((index > 999999999)||(index < 0)) {
		std::cerr << " PNGwriter::pngwriter_rename - ERROR **: Numerical name is out of 0 - 999 999 999 range (" << index <<")." << std::endl;
		return;
	}

	if(0>  sprintf(buffer, "%9.9lu.png",index)) {
		std::cerr << " PNGwriter::pngwriter_rename - ERROR **: Error creating numerical filename." << std::endl;
		return;
	}

	delete [] filename_;
	delete [] texttitle_;

	filename_ = new char[strlen(buffer)+1];
	texttitle_ = new char[strlen(buffer)+1];

	strcpy(filename_,buffer);
	strcpy(texttitle_,buffer);

};

///////////////////////////////////////////////////////
void pngwriter::settext(char* title, char* author, char* description, char* software) {
	delete [] textauthor_;
	delete [] textdescription_;
	delete [] texttitle_;
	delete [] textsoftware_;

	textauthor_ = new char[strlen(author)+1];
	textdescription_ = new char[strlen(description)+1];
	textsoftware_ = new char[strlen(software)+1];
	texttitle_ = new char[strlen(title)+1];

	strcpy(texttitle_, title);
	strcpy(textauthor_, author);
	strcpy(textdescription_, description);
	strcpy(textsoftware_, software);
};

///////////////////////////////////////////////////////
void pngwriter::settext(const char* title, const char* author, const char* description, const char* software) {
	delete [] textauthor_;
	delete [] textdescription_;
	delete [] texttitle_;
	delete [] textsoftware_;

	textauthor_ = new char[strlen(author)+1];
	textdescription_ = new char[strlen(description)+1];
	textsoftware_ = new char[strlen(software)+1];
	texttitle_ = new char[strlen(title)+1];

	strcpy(texttitle_, title);
	strcpy(textauthor_, author);
	strcpy(textdescription_, description);
	strcpy(textsoftware_, software);
};

///////////////////////////////////////////////////////
void pngwriter::close() {
	FILE*            fp;
	png_structp     png_ptr;
	png_infop       info_ptr;

	fp = fopen(filename_, "wb");
	if(fp == NULL) {
		std::cerr << " PNGwriter::close - ERROR **: Error creating file (fopen() returned NULL pointer)." << std::endl;
		perror(" PNGwriter::close - ERROR **");
		return;
	}

	png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
	info_ptr = png_create_info_struct(png_ptr);
	png_init_io(png_ptr, fp);
	if(compressionlevel_ != -2) {
		png_set_compression_level(png_ptr, compressionlevel_);
	} else {
		png_set_compression_level(png_ptr, PNGWRITER_DEFAULT_COMPRESSION);
	}

	png_set_IHDR(png_ptr, info_ptr, width_, height_,
				 bit_depth_, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
				 PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);

	if(filegamma_ < 1.0e-1) {
		filegamma_ = 0.5;  // Modified in 0.5.4 so as to be the same as the usual gamma.
	}

	png_set_gAMA(png_ptr, info_ptr, filegamma_);

	time_t          gmt;
	png_time        mod_time;
	png_text        text_ptr[5];
	time(&gmt);
	png_convert_from_time_t(&mod_time, gmt);
	png_set_tIME(png_ptr, info_ptr, &mod_time);
	text_ptr[0].key = "Title";
	text_ptr[0].text = texttitle_;
	text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
	text_ptr[1].key = "Author";
	text_ptr[1].text = textauthor_;
	text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
	text_ptr[2].key = "Description";
	text_ptr[2].text = textdescription_;
	text_ptr[2].compression = PNG_TEXT_COMPRESSION_NONE;
	text_ptr[3].key = "Creation Time";
	text_ptr[3].text = png_convert_to_rfc1123(png_ptr, &mod_time);
	text_ptr[3].compression = PNG_TEXT_COMPRESSION_NONE;
	text_ptr[4].key = "Software";
	text_ptr[4].text = textsoftware_;
	text_ptr[4].compression = PNG_TEXT_COMPRESSION_NONE;
	png_set_text(png_ptr, info_ptr, text_ptr, 5);

	png_write_info(png_ptr, info_ptr);
	png_write_image(png_ptr, graph_);
	png_write_end(png_ptr, info_ptr);
	png_destroy_write_struct(&png_ptr, &info_ptr);
	fclose(fp);
}

//////////////////////////////////////////////////////
void pngwriter::line(int xfrom, int yfrom, int xto, int yto, int red, int green,int  blue) {
	//  Bresenham Algorithm.
	//
	int dy = yto - yfrom;
	int dx = xto - xfrom;
	int stepx, stepy;

	if(dy < 0) {
		dy = -dy;
		stepy = -1;
	} else {
		stepy = 1;
	}

	if(dx < 0) {
		dx = -dx;
		stepx = -1;
	} else {
		stepx = 1;
	}
	dy <<= 1;     // dy is now 2*dy
	dx <<= 1;     // dx is now 2*dx

	this->plot(xfrom,yfrom,red,green,blue);

	if(dx > dy) {
		int fraction = dy - (dx >> 1);

		while(xfrom != xto) {
			if(fraction >= 0) {
				yfrom += stepy;
				fraction -= dx;
			}
			xfrom += stepx;
			fraction += dy;
			this->plot(xfrom,yfrom,red,green,blue);
		}
	} else {
		int fraction = dx - (dy >> 1);
		while(yfrom != yto) {
			if(fraction >= 0) {
				xfrom += stepx;
				fraction -= dy;
			}
			yfrom += stepy;
			fraction += dx;
			this->plot(xfrom,yfrom,red,green,blue);
		}
	}

}

void pngwriter::line(int xfrom, int yfrom, int xto, int yto, double red, double green,double  blue) {
	this->line(xfrom,
			   yfrom,
			   xto,
			   yto,
			   int (red*65535),
			   int (green*65535),
			   int (blue*65535)
			  );
}

///////////////////////////////////////////////////////////////////////////////////////////
void pngwriter::square(int xfrom, int yfrom, int xto, int yto, int red, int green, int blue) {
	this->line(xfrom, yfrom, xfrom, yto, red, green, blue);
	this->line(xto, yfrom, xto, yto, red, green, blue);
	this->line(xfrom, yfrom, xto, yfrom, red, green, blue);
	this->line(xfrom, yto, xto, yto, red, green, blue);
}

void pngwriter::square(int xfrom, int yfrom, int xto, int yto, double red, double green, double blue) {
	this->square(xfrom,  yfrom,  xto,  yto, int(red*65535), int(green*65535), int(blue*65535));
}

//////////////////////////////////////////////////////////////////////////////////////////////////
void pngwriter::filledsquare(int xfrom, int yfrom, int xto, int yto, int red, int green, int blue) {
	for(int caca = xfrom; caca <xto+1; caca++) {
		this->line(caca, yfrom, caca, yto, red, green, blue);
	}
}

void pngwriter::filledsquare(int xfrom, int yfrom, int xto, int yto, double red, double green, double blue) {
	this->filledsquare(xfrom,  yfrom,  xto,  yto, int(red*65535), int(green*65535), int(blue*65535));
}

//////////////////////////////////////////////////////////////////////////////////////////////////
void pngwriter::circle(int xcentre, int ycentre, int radius, int red, int green, int blue) {
	int x = 0;
	int y = radius;
	int p = (5 - radius*4)/4;

	circle_aux(xcentre, ycentre, x, y, red, green, blue);
	while(x < y) {
		x++;
		if(p < 0) {
			p += 2*x+1;
		} else {
			y--;
			p += 2*(x-y)+1;
		}
		circle_aux(xcentre, ycentre, x, y, red, green, blue);
	}
}

void pngwriter::circle(int xcentre, int ycentre, int radius, double red, double green, double blue) {
	this->circle(xcentre,ycentre,radius, int(red*65535), int(green*65535), int(blue*65535));
}

////////////////////////////////////////////////////////////

void pngwriter::circle_aux(int xcentre, int ycentre, int x, int y, int red, int green, int blue) {
	if(x == 0) {
		this->plot(xcentre, ycentre + y, red, green, blue);
		this->plot(xcentre, ycentre - y, red, green, blue);
		this->plot(xcentre + y, ycentre, red, green, blue);
		this->plot(xcentre - y, ycentre, red, green, blue);
	} else if(x == y) {
		this->plot(xcentre + x, ycentre + y, red, green, blue);
		this->plot(xcentre - x, ycentre + y, red, green, blue);
		this->plot(xcentre + x, ycentre - y, red, green, blue);
		this->plot(xcentre - x, ycentre - y, red, green, blue);
	} else if(x < y) {
		this->plot(xcentre + x, ycentre + y, red, green, blue);
		this->plot(xcentre - x, ycentre + y, red, green, blue);
		this->plot(xcentre + x, ycentre - y, red, green, blue);
		this->plot(xcentre - x, ycentre - y, red, green, blue);
		this->plot(xcentre + y, ycentre + x, red, green, blue);
		this->plot(xcentre - y, ycentre + x, red, green, blue);
		this->plot(xcentre + y, ycentre - x, red, green, blue);
		this->plot(xcentre - y, ycentre - x, red, green, blue);
	}

}

////////////////////////////////////////////////////////////
void pngwriter::filledcircle(int xcentre, int ycentre, int radius, int red, int green, int blue) {
	for(int jjj = ycentre-radius; jjj< ycentre+radius+1; jjj++) {
		this->line(xcentre - int(sqrt((double)(radius*radius) - (-ycentre + jjj)*(-ycentre + jjj))), jjj,
				   xcentre + int(sqrt((double)(radius*radius) - (-ycentre + jjj)*(-ycentre + jjj))),jjj,red,green,blue);
	}
}

void pngwriter::filledcircle(int xcentre, int ycentre, int radius, double red, double green, double blue) {
	this->filledcircle(xcentre, ycentre,  radius, int(red*65535), int(green*65535), int(blue*65535));
}

////////////////Reading routines/////////////////////
/////////////////////////////////////////////////

// Modified with Mikkel's patch
void pngwriter::readfromfile(char* name) {
	FILE*            fp;
	png_structp     png_ptr;
	png_infop       info_ptr;
	unsigned char**   image;
	unsigned long   width, height;
	int bit_depth, color_type, interlace_type;
	//   png_uint_32     i;
	//
	fp = fopen(name,"rb");
	if(fp==NULL) {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file \"" << std::flush;
		std::cerr << name <<std::flush;
		std::cerr << "\"." << std::endl << std::flush;
		perror(" PNGwriter::readfromfile - ERROR **");
		return;
	}

	if(!check_if_png(name, &fp)) {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". This may not be a valid png file. (check_if_png() failed)." << std::endl;
		// fp has been closed already if check_if_png() fails.
		return;
	}

//   Code as it was before Sven's patch
	/*   if(!read_png_info(fp, &png_ptr, &info_ptr))
	     {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_info() failed." << std::endl;
		// fp has been closed already if read_png_info() fails.
		return;
	     }

	   if(!read_png_image(fp, png_ptr, info_ptr, &image, &width, &height))
	     {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_image() failed." << std::endl;
		// fp has been closed already if read_png_image() fails.
		return;
	     }

	   //stuff should now be in image[][].

	 */ //End of code as it was before Sven's patch.

	//Sven's patch starts here
	////////////////////////////////////

	/*

	if(!read_png_info(fp, &png_ptr, &info_ptr))
	  {

	std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_info() failed." << std::endl;
	// fp has been closed already if read_png_info() fails.
	return;
	  }

	// UPDATE: Query info struct to get header info BEFORE reading the image

	png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
	bit_depth_ = bit_depth;
	colortype_ = color_type;

	if(color_type == PNG_COLOR_TYPE_PALETTE)
	  {
	png_set_expand(png_ptr);
	png_read_update_info(png_ptr, info_ptr);
	  }

	if(!read_png_image(fp, png_ptr, info_ptr, &image, &width, &height))
	  {
	std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_image() failed." << std::endl;
	// fp has been closed already if read_png_image() fails.
	return;
	  }

	//stuff should now be in image[][].
	*/
	//Sven's patch ends here.
	////////////////////////////////

	// Mikkel's patch starts here
	// ///////////////////////////////////

	if(!read_png_info(fp, &png_ptr, &info_ptr)) {

		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_info() failed." << std::endl;
		// fp has been closed already if read_png_info() fails.
		return;
	}

	//Input transformations
	png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
	bit_depth_ = bit_depth;
	colortype_ = color_type;


	// Changes palletted image to RGB
	if(color_type == PNG_COLOR_TYPE_PALETTE /*&& bit_depth<8*/) {
		// png_set_expand(png_ptr);
		png_set_palette_to_rgb(png_ptr);  // Just an alias of png_set_expand()
		transformation_ = 1;
	}

	// Transforms grescale images of less than 8 bits to 8 bits.
	if(color_type == PNG_COLOR_TYPE_GRAY && bit_depth<8) {
		// png_set_expand(png_ptr);
		png_set_gray_1_2_4_to_8(png_ptr);  // Just an alias of the above.
		transformation_ = 1;
	}

	// Completely strips the alpha channel.
	if(color_type & PNG_COLOR_MASK_ALPHA) {
		png_set_strip_alpha(png_ptr);
		transformation_ = 1;
	}

	// Converts greyscale images to RGB.
	if(color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA) { // Used to be RGB, fixed it.
		png_set_gray_to_rgb(png_ptr);
		transformation_ = 1;
	}

	// If any of the above were applied,
	if(transformation_) {
		// png_set_gray_to_rgb(png_ptr);   //Is this really needed here?

		// After setting the transformations, libpng can update your png_info structure to reflect any transformations
		// you've requested with this call. This is most useful to update the info structure's rowbytes field so you can
		// use it to allocate your image memory. This function will also update your palette with the correct screen_gamma
		// and background if these have been given with the calls above.

		png_read_update_info(png_ptr, info_ptr);

		// Just in case any of these have changed?
		png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
		bit_depth_ = bit_depth;
		colortype_ = color_type;
	}

	if(!read_png_image(fp, png_ptr, info_ptr, &image, &width, &height)) {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". read_png_image() failed." << std::endl;
		// fp has been closed already if read_png_image() fails.
		return;
	}

	//stuff should now be in image[][].

	// Mikkel's patch ends here
	// //////////////////////////////
	//
	if(image == NULL) {
		std::cerr << " PNGwriter::readfromfile - ERROR **: Error opening file " << name << ". Can't assign memory (after read_png_image(), image is NULL)." << std::endl;
		fclose(fp);
		return;
	}

	//First we must get rid of the image already there, and free the memory.
	int jjj;
	for(jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
	free(graph_);

	//Must reassign the new size of the read image
	width_ = width;
	height_ = height;

	//Graph now is the image.
	graph_ = image;

	rowbytes_ = png_get_rowbytes(png_ptr, info_ptr);

	// This was part of the original source, but has been moved up.
	/*
	   png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL);
	   bit_depth_ = bit_depth;
	   colortype_ = color_type;
	*/
	// if(color_type == PNG_COLOR_TYPE_PALETTE /*&& bit_depth<8*/   )
	/*    {
	png_set_expand(png_ptr);
	    }

	  if(color_type == PNG_COLOR_TYPE_GRAY && bit_depth<8)
	    {
	png_set_expand(png_ptr);
	    }

	  if(color_type & PNG_COLOR_MASK_ALPHA)
	    {
	png_set_strip_alpha(png_ptr);
	    }

	  if(color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_RGB_ALPHA)
	    {
	png_set_gray_to_rgb(png_ptr);
	    }

	*/

	if((bit_depth_ !=16)&&(bit_depth_ !=8)) {
		std::cerr << " PNGwriter::readfromfile() - WARNING **: Input file is of unsupported type (bad bit_depth). Output will be unpredictable.\n";
	}

// Thanks to Mikkel's patch, PNGwriter should now be able to handle these color types:

	/*
	color_type     - describes which color/alpha channels are present.
	                     PNG_COLOR_TYPE_GRAY                        (bit depths 1, 2, 4, 8, 16)
	                     PNG_COLOR_TYPE_GRAY_ALPHA                        (bit depths 8, 16)
						 PNG_COLOR_TYPE_PALETTE                        (bit depths 1, 2, 4, 8)
	                     PNG_COLOR_TYPE_RGB                        (bit_depths 8, 16)
	                     PNG_COLOR_TYPE_RGB_ALPHA                        (bit_depths 8, 16)

	                     PNG_COLOR_MASK_PALETTE
	                     PNG_COLOR_MASK_COLOR

	color types.  Note that not all combinations are legal
	#define PNG_COLOR_TYPE_GRAY 0
	#define PNG_COLOR_TYPE_PALETTE  (PNG_COLOR_MASK_COLOR (2) | PNG_COLOR_MASK_PALETTE (1) )
	#define PNG_COLOR_TYPE_RGB        (PNG_COLOR_MASK_COLOR (2) )
	#define PNG_COLOR_TYPE_RGB_ALPHA  (PNG_COLOR_MASK_COLOR (2) | PNG_COLOR_MASK_ALPHA (4) )
	#define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA (4) )

	aliases
	#define PNG_COLOR_TYPE_RGBA  PNG_COLOR_TYPE_RGB_ALPHA
	#define PNG_COLOR_TYPE_GA  PNG_COLOR_TYPE_GRAY_ALPHA

	 These describe the color_type field in png_info.
	 color type masks
	#define PNG_COLOR_MASK_PALETTE    1
	#define PNG_COLOR_MASK_COLOR      2
	#define PNG_COLOR_MASK_ALPHA      4


						 */


	if(colortype_ !=2) {
		std::cerr << " PNGwriter::readfromfile() - WARNING **: Input file is of unsupported type (bad color_type). Output will be unpredictable.\n";
	}

	screengamma_ = 2.2;
	double          file_gamma,screen_gamma;
	screen_gamma = screengamma_;
	if(png_get_gAMA(png_ptr, info_ptr, &file_gamma)) {
		png_set_gamma(png_ptr,screen_gamma,file_gamma);
	} else {
		png_set_gamma(png_ptr, screen_gamma,0.45);
	}

	filegamma_ = file_gamma;

	fclose(fp);
}

///////////////////////////////////////////////////////

void pngwriter::readfromfile(const char* name) {
	this->readfromfile((char *)(name));
}

/////////////////////////////////////////////////////////
int pngwriter::check_if_png(char* file_name, FILE** fp) {
	char    sig[PNG_BYTES_TO_CHECK];

	if(/*(*fp = fopen(file_name, "rb")) */  *fp == NULL) { // Fixed 10 10 04
		//   exit(EXIT_FAILURE);
		std::cerr << " PNGwriter::check_if_png - ERROR **: Could not open file  " << file_name << " to read." << std::endl;
		perror(" PNGwriter::check_if_png - ERROR **");
		return 0;
	}

	if(fread(sig, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK) {
		//exit(EXIT_FAILURE);
		std::cerr << " PNGwriter::check_if_png - ERROR **: File " << file_name << " does not appear to be a valid PNG file." << std::endl;
		perror(" PNGwriter::check_if_png - ERROR **");
		fclose(*fp);
		return 0;
	}

	if(png_sig_cmp((png_bytep) sig, (png_size_t)0, PNG_BYTES_TO_CHECK) /*png_check_sig((png_bytep) sig, PNG_BYTES_TO_CHECK)*/) {
		std::cerr << " PNGwriter::check_if_png - ERROR **: File " << file_name << " does not appear to be a valid PNG file. png_check_sig() failed." << std::endl;
		fclose(*fp);
		return 0;
	}



	return 1; //Success
}

///////////////////////////////////////////////////////
int pngwriter::read_png_info(FILE* fp, png_structp* png_ptr, png_infop* info_ptr) {
	*png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
	if(*png_ptr == NULL) {
		std::cerr << " PNGwriter::read_png_info - ERROR **: Could not create read_struct." << std::endl;
		fclose(fp);
		return 0;
		//exit(EXIT_FAILURE);
	}
	*info_ptr = png_create_info_struct(*png_ptr);
	if(*info_ptr == NULL) {
		png_destroy_read_struct(png_ptr, (png_infopp)NULL, (png_infopp)NULL);
		std::cerr << " PNGwriter::read_png_info - ERROR **: Could not create info_struct." << std::endl;
		//exit(EXIT_FAILURE);
		fclose(fp);
		return 0;
	}
	if(setjmp((*png_ptr)->jmpbuf)) /*(setjmp(png_jmpbuf(*png_ptr)) )*/ /////////////////////////////////////
	{
		png_destroy_read_struct(png_ptr, info_ptr, (png_infopp)NULL);
		std::cerr << " PNGwriter::read_png_info - ERROR **: This file may be a corrupted PNG file. (setjmp(*png_ptr)->jmpbf) failed)." << std::endl;
		fclose(fp);
		return 0;
		//exit(EXIT_FAILURE);
	}
	png_init_io(*png_ptr, fp);
	png_set_sig_bytes(*png_ptr, PNG_BYTES_TO_CHECK);
	png_read_info(*png_ptr, *info_ptr);

	return 1;
}

////////////////////////////////////////////////////////////
int pngwriter::read_png_image(FILE* fp, png_structp png_ptr, png_infop info_ptr,
							  png_bytepp* image, png_uint_32* width, png_uint_32* height) {
	unsigned int i,j;

	*width = png_get_image_width(png_ptr, info_ptr);
	*height = png_get_image_height(png_ptr, info_ptr);

	if(width == NULL) {
		std::cerr << " PNGwriter::read_png_image - ERROR **: png_get_image_width() returned NULL pointer." << std::endl;
		fclose(fp);
		return 0;
	}

	if(height == NULL) {
		std::cerr << " PNGwriter::read_png_image - ERROR **: png_get_image_height() returned NULL pointer." << std::endl;
		fclose(fp);
		return 0;
	}

	if((*image = (png_bytepp)malloc(*height * sizeof(png_bytep))) == NULL) {
		std::cerr << " PNGwriter::read_png_image - ERROR **: Could not allocate memory for reading image." << std::endl;
		fclose(fp);
		return 0;
		//exit(EXIT_FAILURE);
	}
	for(i = 0; i < *height; i++) {
		(*image)[i] = (png_bytep)malloc(png_get_rowbytes(png_ptr, info_ptr));
		if((*image)[i] == NULL) {
			for(j = 0; j < i; j++) free((*image)[j]);
			free(*image);
			fclose(fp);
			std::cerr << " PNGwriter::read_png_image - ERROR **: Could not allocate memory for reading image." << std::endl;
			return 0;
			//exit(EXIT_FAILURE);
		}
	}
	png_read_image(png_ptr, *image);

	return 1;
}

///////////////////////////////////
int pngwriter::getheight(void) {
	return height_;
}

int pngwriter::getwidth(void) {
	return width_;
}


int pngwriter::getbitdepth(void) {
	return bit_depth_;
}

int pngwriter::getcolortype(void) {
	return colortype_;
}

double pngwriter::getgamma(void) {
	return filegamma_;
}

void pngwriter::setgamma(double gamma) {
	filegamma_ = gamma;
}

// The algorithms HSVtoRGB and RGBtoHSV were found at http://www.cs.rit.edu/~ncs/
//  which is a page that belongs to Nan C. Schaller, though
//  these algorithms appear to be the work of Eugene Vishnevsky.
//////////////////////////////////////////////
void pngwriter::HSVtoRGB(double* r, double* g, double* b, double h, double s, double v) {
	// r,g,b values are from 0 to 1
	// h = [0,1], s = [0,1], v = [0,1]
	// if s == 0, then h = -1 (undefined)
	//
	h = h*360.0;

	int i;
	double f, p, q, t;
	if(s == 0) {
		// achromatic (grey)
		*r = *g = *b = v;
		return;
	}

	h /= 60;                        // sector 0 to 5
	i = int(floor(h));
	f = h - i;                      // factorial part of h
	p = v * (1 - s);
	q = v * (1 - s * f);
	t = v * (1 - s * (1 - f));

	switch(i) {
	case 0:
		*r = v;
		*g = t;
		*b = p;
		break;
	case 1:
		*r = q;
		*g = v;
		*b = p;
		break;
	case 2:
		*r = p;
		*g = v;
		*b = t;
		break;
	case 3:
		*r = p;
		*g = q;
		*b = v;
		break;
	case 4:
		*r = t;
		*g = p;
		*b = v;
		break;
	default:                // case 5:
		*r = v;
		*g = p;
		*b = q;
		break;
	}
}

void pngwriter::RGBtoHSV(float r, float g, float b, float* h, float* s, float* v) {

	float min=0.0; //These values are not used.
	float max=1.0;
	float delta;

	if((r>=g)&&(r>=b)) {
		max = r;
	}
	if((g>=r)&&(g>=b)) {
		max = g;
	}
	if((b>=g)&&(b>=r)) {
		max = b;
	}

	if((r<=g)&&(r<=b)) {
		min = r;
	}
	if((g<=r)&&(g<=b)) {
		min = g;
	}
	if((b<=g)&&(b<=r)) {
		min = b;
	}

	*v = max;                               // v

	delta = max - min;

	if(max != 0)
		*s = delta / max;               // s
	else {

		r = g = b = 0;                // s = 0, v is undefined
		*s = 0;
		*h = -1;
		return;
	}

	if(r == max)
		*h = (g - b) / delta;           // between yellow & magenta
	else if(g == max)
		*h = 2 + (b - r) / delta;       // between cyan & yellow
	else
		*h = 4 + (r - g) / delta;       // between magenta & cyan

	*h *= 60;                               // degrees
	if(*h < 0)
		*h += 360;

}

//
//////////////////////////////////////////////////////////////////////////////////
void pngwriter::plotHSV(int x, int y, double hue, double saturation, double value) {
	double red,green,blue;
	double* redp;
	double* greenp;
	double* bluep;

	redp = &red;
	greenp = &green;
	bluep = &blue;

	HSVtoRGB(redp,greenp,bluep,hue,saturation,value);
	plot(x,y,red,green,blue);
}

void pngwriter::plotHSV(int x, int y, int hue, int saturation, int value) {
	plotHSV(x, y, double(hue)/65535.0, double(saturation)/65535.0,  double(value)/65535.0);
}

//
//////////////////////////////////////////////////////////////////////////////////
double pngwriter::dreadHSV(int x, int y, int colour) {
	if((x>0)&&(x<=width_)&&(y>0)&&(y<=height_)) {

		float* huep;
		float* saturationp;
		float* valuep;
		float red,green,blue;
		float hue, saturation, value;

		red = float(dread(x,y,1));
		green = float(dread(x,y,2));
		blue = float(dread(x,y,3));

		huep = &hue;
		saturationp = &saturation;
		valuep = &value;

		RGBtoHSV(red,  green,  blue, huep,  saturationp, valuep);

		if(colour == 1) {
			return double(hue)/360.0;
		}

		else if(colour == 2) {
			return saturation;
		}

		else if(colour == 3) {
			return value;
		}

		std::cerr << " PNGwriter::dreadHSV - ERROR **: Called with wrong colour argument: should be 1, 2 or 3; was: " << colour << "." << std::endl;
	}
	return 0.0;
}

//
//////////////////////////////////////////////////////////////////////////////////
int pngwriter::readHSV(int x, int y, int colour) {
	if((x>0)&&(x<=width_)&&(y>0)&&(y<=height_)) {

		float* huep;
		float* saturationp;
		float* valuep;
		float red,green,blue;
		float hue, saturation, value;

		red = float(dread(x,y,1));
		green = float(dread(x,y,2));
		blue = float(dread(x,y,3));

		huep = &hue;
		saturationp = &saturation;
		valuep = &value;

		RGBtoHSV(red,  green,  blue, huep,  saturationp, valuep);

		if(colour == 1) {
			return int(65535*(double(hue)/360.0));
		}

		else if(colour == 2) {
			return int(65535*saturation);
		}

		else if(colour == 3) {
			return int(65535*value);
		}

		std::cerr << " PNGwriter::readHSV - ERROR **: Called with wrong colour argument: should be 1, 2 or 3; was: " << colour << "." << std::endl;
		return 0;
	} else {
		return 0;
	}
}

void pngwriter::setcompressionlevel(int level) {
	if((level < -1)||(level > 9)) {
		std::cerr << " PNGwriter::setcompressionlevel - ERROR **: Called with wrong compression level: should be -1 to 9, was: " << level << "." << std::endl;
	}
	compressionlevel_ = level;
}

// An implementation of a Bezier curve.
void pngwriter::bezier(int startPtX, int startPtY,
					   int startControlX, int startControlY,
					   int endPtX, int endPtY,
					   int endControlX, int endControlY,
					   double red, double green, double blue) {

	double cx = 3.0*(startControlX - startPtX);
	double bx = 3.0*(endControlX - startControlX) - cx;
	double ax = double(endPtX - startPtX - cx - bx);

	double cy = 3.0*(startControlY - startPtY);
	double by = 3.0*(endControlY - startControlY) - cy;
	double ay = double(endPtY - startPtY - cy - by);

	double x,y,newx,newy;
	x = startPtX;
	y = startPtY;

	for(double t = 0.0; t<=1.005; t += 0.005) {
		newx = startPtX + t*(double(cx) + t*(double(bx) + t*(double(ax))));
		newy = startPtY + t*(double(cy) + t*(double(by) + t*(double(ay))));
		this->line(int(x),int(y),int(newx),int(newy),red,green,blue);
		x = newx;
		y = newy;
	}
}

//int version of bezier
void pngwriter::bezier(int startPtX, int startPtY,
					   int startControlX, int startControlY,
					   int endPtX, int endPtY,
					   int endControlX, int endControlY,
					   int  red, int  green, int blue) {
	this->bezier(startPtX,  startPtY,
				 startControlX, startControlY,
				 endPtX, endPtY,
				 endControlX,  endControlY,
				 double(red)/65535.0,  double(green)/65535.0,  double(blue)/65535.0);
}

/*
int pngwriter::getcompressionlevel(void)
{
   return png_get_compression_level(png_ptr);
}
*/

double pngwriter::version(void) {
	const char* a = "Jeramy Webb (jeramyw@gmail.com), Mike Heller (mkheller@gmail.com)"; // For their generosity ;-)
	char b = a[27];
	b++;
	return (PNGWRITER_VERSION);
}

void pngwriter::write_png(void) {
	this->close();
}

#ifndef NO_FREETYPE

// Freetype-based text rendering functions.
///////////////////////////////////////////
void pngwriter::plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double red, double green, double blue) {
	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(cos(angle)*0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(-sin(angle)*0x10000);   /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(sin(angle)*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(cos(angle)*0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = x_start*64 ;
	pen.y = (int)(y_start/64.0);

	/*Count the length of the string */
	int num_chars = strlen(text);

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not init Library."<< std::endl; return;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return; } else if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not find or load font file."<< std::endl; return; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(((double) delta.x)*cos(angle));
			pen.y += (int)(((double) delta.x)*(sin(angle)));
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Set char size error." << std::endl; return;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return;}

		/* Convert to an anti-aliased bitmap */
		//	error = FT_Render_Glyph( face->glyph, FT_RENDER_MODE_NORMAL );
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Render glyph error." << std::endl; return;}

		/* Now, draw to our target surface */
		my_draw_bitmap(&slot->bitmap,
					   slot->bitmap_left,
					   y_start + slot->bitmap_top,
					   red,
					   green,
					   blue);

		/* Advance to the next position */
		pen.x += slot->advance.x;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}

	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);
}

void pngwriter::plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle,  char* text, double red, double green, double blue) {
	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(cos(angle)*0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(-sin(angle)*0x10000);   /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(sin(angle)*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(cos(angle)*0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = x_start*64 ;
	pen.y = (int)(y_start/64.0);

	/*Count the length of the string */
	int num_bytes=0;
	while(text[num_bytes]!=0) {
		num_bytes++;
	}

	/*
	   std::cout << "Num bytes is: "<< num_bytes << std::endl;
	   */

	//The array of ucs4 glyph indexes, which will by at most the number of bytes in the utf-8 file.
	long* ucs4text;
	ucs4text = new long[num_bytes+1];

	unsigned char u,v,w,x,y,z;

	int num_chars=0;

	long iii=0;

	while(iii<num_bytes) {
		z = text[iii];

		if(z<=127) {
			ucs4text[num_chars] = z;
		}

		if((192<=z)&&(z<=223)) {
			iii++;
			y = text[iii];
			ucs4text[num_chars] = (z-192)*64 + (y -128);
		}

		if((224<=z)&&(z<=239)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			ucs4text[num_chars] = (z-224)*4096 + (y -128)*64 + (x-128);
		}

		if((240<=z)&&(z<=247)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			ucs4text[num_chars] = (z-240)*262144 + (y -128)*4096 + (x-128)*64 + (w-128);
		}

		if((248<=z)&&(z<=251)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			ucs4text[num_chars] = (z-248)*16777216 + (y -128)*262144 + (x-128)*4096 + (w-128)*64 +(v-128);
		}

		if((252==z)||(z==253)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			u = text[iii];
			ucs4text[num_chars] = (z-252)*1073741824 + (y -128)*16777216   + (x-128)*262144 + (w-128)*4096 +(v-128)*64 + (u-128);
		}

		if((z==254)||(z==255)) {
			std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: Problem with character: invalid UTF-8 data."<< std::endl;
		}
		// std::cerr << "\nProblem at " << iii << ".\n";
		//
		iii++;
		num_chars++;
	}

	// num_chars now contains the number of characters in the string.
	/*
	std::cout << "Num chars is: "<< num_chars << std::endl;
	*/

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: FreeType: Could not init Library."<< std::endl; return;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return; } else if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not find or load font file."<< std::endl; return; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(((double) delta.x)*cos(angle));
			pen.y += (int)(((double) delta.x)*(sin(angle)));
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: FreeType: Set char size error." << std::endl; return;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return;}

		/* Convert to an anti-aliased bitmap */
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::plot_text_utf8 - ERROR **: FreeType: Render glyph error." << std::endl; return;}

		/* Now, draw to our target surface */
		my_draw_bitmap(&slot->bitmap,
					   slot->bitmap_left,
					   y_start + slot->bitmap_top,
					   red,
					   green,
					   blue);

		/* Advance to the next position */
		pen.x += slot->advance.x;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}

	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);

	delete[] ucs4text;
}

void pngwriter::plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue) {
	plot_text(face_path, fontsize, x_start, y_start,  angle,  text, ((double) red)/65535.0, ((double) green)/65535.0, ((double) blue)/65535.0);
}

void pngwriter::plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue) {
	plot_text_utf8(face_path, fontsize, x_start, y_start,  angle,  text, ((double) red)/65535.0, ((double) green)/65535.0, ((double) blue)/65535.0);
}

void pngwriter::my_draw_bitmap(FT_Bitmap* bitmap, int x, int y, double red, double green, double blue) {
	double temp;
	for(int j=1; j<bitmap->rows+1; j++) {
		for(int i=1; i< bitmap->width + 1; i++) {
			temp = (double)(bitmap->buffer[(j-1)*bitmap->width + (i-1)])/255.0;

			if(temp) {
				this->plot(x + i,
						   y  - j,
						   temp*red + (1-temp)*(this->dread(x+i,y-j,1)),
						   temp*green + (1-temp)*(this->dread(x+i,y-j,2)),
						   temp*blue + (1-temp)*(this->dread(x+i,y-j,3))
						  );
			}
		}
	}
}



//////////// Get text width

//put in freetype section

int pngwriter::get_text_width(char* face_path, int fontsize, char* text) {

	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(1.0*0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(0.0*0x10000);    /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(0.0*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(1.0*0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = 0;
	pen.y = 0;

	/*Count the length of the string */
	int num_chars = strlen(text);

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Could not init Library."<< std::endl; return 0;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return 0; } else if(error) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Could not find or load font file." << std::endl; return 0; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(delta.x);
			pen.y +=  0;
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Set char size error." << std::endl; return 0;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return 0;}

		/* Convert to an anti-aliased bitmap */
		//	error = FT_Render_Glyph( face->glyph, FT_RENDER_MODE_NORMAL );
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::get_text_width - ERROR **: FreeType: Render glyph error." << std::endl; return 0;}

		/* Now, draw to our target surface */
		/*	my_draw_bitmap( &slot->bitmap,
					slot->bitmap_left,
					slot->bitmap_top,
					red,
					green,
					blue );
		*/
		/* Advance to the next position */
		pen.x += slot->advance.x;
//	std::cout << ((double) pen.x)/64.0 << std::endl;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}


	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);

	return (int)(((double)pen.x)/64.0);
}


int pngwriter::get_text_width_utf8(char* face_path, int fontsize,  char* text) {
	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(0*0x10000);    /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(0*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = 0 ;
	pen.y = 0;

	/*Count the length of the string */
	int num_bytes=0;
	while(text[num_bytes]!=0) {
		num_bytes++;
	}

	/*
	   std::cout << "Num bytes is: "<< num_bytes << std::endl;
	   */

	//The array of ucs4 glyph indexes, which will by at most the number of bytes in the utf-8 file.
	long* ucs4text;
	ucs4text = new long[num_bytes+1];

	unsigned char u,v,w,x,y,z;

	int num_chars=0;

	long iii=0;

	while(iii<num_bytes) {
		z = text[iii];

		if(z<=127) {
			ucs4text[num_chars] = z;
		}

		if((192<=z)&&(z<=223)) {
			iii++;
			y = text[iii];
			ucs4text[num_chars] = (z-192)*64 + (y -128);
		}

		if((224<=z)&&(z<=239)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			ucs4text[num_chars] = (z-224)*4096 + (y -128)*64 + (x-128);
		}

		if((240<=z)&&(z<=247)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			ucs4text[num_chars] = (z-240)*262144 + (y -128)*4096 + (x-128)*64 + (w-128);
		}

		if((248<=z)&&(z<=251)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			ucs4text[num_chars] = (z-248)*16777216 + (y -128)*262144 + (x-128)*4096 + (w-128)*64 +(v-128);
		}

		if((252==z)||(z==253)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			u = text[iii];
			ucs4text[num_chars] = (z-252)*1073741824 + (y -128)*16777216   + (x-128)*262144 + (w-128)*4096 +(v-128)*64 + (u-128);
		}

		if((z==254)||(z==255)) {
			std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: Problem with character: invalid UTF-8 data."<< std::endl;
		}
		// std::cerr << "\nProblem at " << iii << ".\n";
		//
		iii++;
		num_chars++;
	}

	// num_chars now contains the number of characters in the string.
	/*
	std::cout << "Num chars is: "<< num_chars << std::endl;
	*/

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: FreeType: Could not init Library."<< std::endl; return 0;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return 0; } else if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not find or load font file."<< std::endl; return 0; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(delta.x);
			pen.y +=  0;
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: FreeType: Set char size error." << std::endl; return 0;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return 0;}

		/* Convert to an anti-aliased bitmap */
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **: FreeType: Render glyph error." << std::endl; return 0;}

		/* Now, draw to our target surface */
		/*	my_draw_bitmap( &slot->bitmap,
					slot->bitmap_left,
					y_start + slot->bitmap_top,
					red,
					green,
					blue );
		*/
		/* Advance to the next position */
		pen.x += slot->advance.x;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}

	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);

	delete[] ucs4text;

	return (int)(((double) pen.x)/64.0);
}

///////////////
#endif
#ifdef NO_FREETYPE

void pngwriter::plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue) {
	std::cerr << " PNGwriter::plot_text - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

void pngwriter::plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double red, double green, double blue) {
	std::cerr << " PNGwriter::plot_text - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;

}

void pngwriter::plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue) {
	std::cerr << " PNGwriter::plot_text_utf8 - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

void pngwriter::plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double red, double green, double blue) {
	std::cerr << " PNGwriter::plot_text_utf8 - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

//////////// Get text width
int pngwriter::get_text_width(char* face_path, int fontsize, char* text) {
	std::cerr << " PNGwriter::get_text_width - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return 0;
}


int pngwriter::get_text_width_utf8(char* face_path, int fontsize,  char* text) {
	std::cerr << " PNGwriter::get_text_width_utf8 - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return 0;
}

///////////////
#endif

/////////////////////////////////////
int pngwriter::bilinear_interpolation_read(double x, double y, int colour) {

	int inty, intx;
	inty = (int) ceil(y);
	intx = (int) ceil(x);

	//inty = (int) floor(y) +1;
	// intx = (int) floor(x) +1;
	//
	bool attop, atright;
	attop = inty==this->height_;
	atright =  intx==this->width_;
	/*
	   if( intx==this->width_ +1)
	     {
		intx--;
		//	std::cout << "intx--" << std::endl;

	     }
	  */
	/*
	if(inty == this->height_ +1)
	  {
	inty--;
	//	std::cout << "inty--" << std::endl;
	  }
	*/

	if((!attop)&&(!atright)) {

		double f,g,f1,g1;
		f = 1.0 + x - ((double) intx);
		g = 1.0 + y - ((double) inty);
		f1 = 1.0 - f;
		g1 = 1.0 - g;

		return (int)(
				   f1*g1*this->read(intx, inty,colour)
				   + f*g1*this->read(intx+1,inty,colour)
				   +f1*g*this->read(intx,inty+1,colour)
				   + f*g*(this->read(intx+1,inty+1,colour))
			   );
	}

	if((atright)&&(!attop)) {

		double f,g,f1,g1;
		f = 1.0 + x - ((double) intx);
		g = 1.0 + y - ((double) inty);
		f1 = 1.0 - f;
		g1 = 1.0 - g;

		return (int)(
				   f1*g1*this->read(intx, inty,colour)
				   + f*g1*(2*(this->read(intx,inty,colour)) - (this->read(intx-1,inty,colour)))
				   +f1*g*this->read(intx,inty+1,colour)
				   + f*g*(2*(this->read(intx,inty+1,colour)) - (this->read(intx-1,inty+1,colour)))
			   );
	}

	if((attop)&&(!atright)) {
		double f,g,f1,g1;
		f = 1.0 + x - ((double) intx);
		g = 1.0 + y - ((double) inty);
		f1 = 1.0 - f;
		g1 = 1.0 - g;

		return (int)(
				   f1*g1*this->read(intx, inty,colour)
				   + f*g1*this->read(intx+1,inty,colour)
				   +f1*g*(2*(this->read(intx,inty,colour))  - this->read(intx,inty-1,colour))
				   + f*g*(2*(this->read(intx+1,inty,colour))  - this->read(intx+1,inty-1,colour))
			   );
	}

	double f,g,f1,g1;
	f = 1.0 + x - ((double) intx);
	g = 1.0 + y - ((double) inty);
	f1 = 1.0 - f;
	g1 = 1.0 - g;

	return (int)(
			   f1*g1*this->read(intx, inty,colour)
			   + f*g1*(2*(this->read(intx,inty,colour)) - (this->read(intx-1,inty,colour)))
			   +f1*g*(2*(this->read(intx,inty,colour))  - this->read(intx,inty-1,colour))
			   + f*g*(2*(2*(this->read(intx,inty,colour)) - (this->read(intx-1,inty,colour)))  - (2*(this->read(intx,inty-1,colour)) - (this->read(intx-1,inty-1,colour))))
		   );

	/*
	 return (int) (
	 f1*g1*this->read(intx, inty,colour)
	 + f*g1*this->read(intx+1,inty,colour)
	 +f1*g*this->read(intx,inty+1,colour)
	 + f*g*this->read(intx+1, inty+1,colour)
	 );
	 * */

};

double pngwriter::bilinear_interpolation_dread(double x, double y, int colour) {
	return double(this->bilinear_interpolation_read(x,y,colour))/65535.0;
};

void pngwriter::plot_blend(int x, int y, double opacity, int red, int green, int blue) {
	this->plot(x, y,
			   (int)(opacity*red   +  this->read(x,y,1)*(1.0-opacity)),
			   (int)(opacity*green +  this->read(x,y,2)*(1.0-opacity)),
			   (int)(opacity*blue  +  this->read(x,y,3)*(1.0-opacity))
			  );
};

void pngwriter::plot_blend(int x, int y, double opacity, double red, double green, double blue) {
	this->plot_blend(x, y, opacity, (int)(65535*red), (int)(65535*green), (int)(65535*blue));
};

void pngwriter::invert(void) {
	//   int temp1, temp2, temp3;
	double temp11, temp22, temp33;

	for(int jjj = 1; jjj <= (this->height_); jjj++) {
		for(int iii = 1; iii <= (this->width_); iii++) {
			/*	     temp11 = (this->read(iii,jjj,1));
			 temp22 = (this->read(iii,jjj,2));
			 temp33 = (this->read(iii,jjj,3));
			 *
			 this->plot(iii,jjj,
			 ((double)(65535 - temp11))/65535.0,
			 ((double)(65535 - temp22))/65535.0,
			 ((double)(65535 - temp33))/65535.0
			 );
			 *
			 */
			temp11 = (this->read(iii,jjj,1));
			temp22 = (this->read(iii,jjj,2));
			temp33 = (this->read(iii,jjj,3));

			this->plot(iii,jjj,
					   (int)(65535 - temp11),
					   (int)(65535 - temp22),
					   (int)(65535 - temp33)
					  );

		}
	}
}

void pngwriter::resize(int width, int height) {

	for(int jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
	free(graph_);

	width_ = width;
	height_ = height;
	backgroundcolour_ = 0;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::resize - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(int kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::resize - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::resize - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			//graph_[vhhh][6*hhh + i] where i goes from 0 to 5
			tempindex = 6*hhh;
			graph_[vhhh][tempindex] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+1] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+2] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+3] = (char)(backgroundcolour_%256);
			graph_[vhhh][tempindex+4] = (char) floor(((double)backgroundcolour_)/256);
			graph_[vhhh][tempindex+5] = (char)(backgroundcolour_%256);
		}
	}
}

void pngwriter::boundary_fill(int xstart, int ystart, double boundary_red,double boundary_green,double boundary_blue,double fill_red, double fill_green, double fill_blue) {
	if((
				(this->dread(xstart,ystart,1) != boundary_red) ||
				(this->dread(xstart,ystart,2) != boundary_green) ||
				(this->dread(xstart,ystart,3) != boundary_blue)
			)
			&&
			(
				(this->dread(xstart,ystart,1) != fill_red) ||
				(this->dread(xstart,ystart,2) != fill_green) ||
				(this->dread(xstart,ystart,3) != fill_blue)
			)
			&&
			(xstart >0)&&(xstart <= width_)&&(ystart >0)&&(ystart <= height_)
	  ) {
		this->plot(xstart, ystart, fill_red, fill_green, fill_blue);
		boundary_fill(xstart+1,  ystart,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill(xstart,  ystart+1,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill(xstart,  ystart-1,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill(xstart-1,  ystart,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
	}
}

//no int version needed
void pngwriter::flood_fill_internal(int xstart, int ystart,  double start_red, double start_green, double start_blue, double fill_red, double fill_green, double fill_blue) {
	if((
				(this->dread(xstart,ystart,1) == start_red) &&
				(this->dread(xstart,ystart,2) == start_green) &&
				(this->dread(xstart,ystart,3) == start_blue)
			)
			&&
			(
				(this->dread(xstart,ystart,1) != fill_red) ||
				(this->dread(xstart,ystart,2) != fill_green) ||
				(this->dread(xstart,ystart,3) != fill_blue)
			)
			&&
			(xstart >0)&&(xstart <= width_)&&(ystart >0)&&(ystart <= height_)
	  ) {
		this->plot(xstart, ystart, fill_red, fill_green, fill_blue);
		flood_fill_internal(xstart+1,  ystart,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal(xstart-1,  ystart,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal(xstart,  ystart+1,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal(xstart,  ystart-1,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
	}

}

//int version
void pngwriter::boundary_fill(int xstart, int ystart, int boundary_red,int boundary_green,int boundary_blue,int fill_red, int fill_green, int fill_blue) {

	this->boundary_fill(xstart, ystart,
						((double) boundary_red)/65535.0,
						((double) boundary_green)/65535.0,
						((double) boundary_blue)/65535.0,
						((double) fill_red)/65535.0,
						((double) fill_green)/65535.0,
						((double) fill_blue)/65535.0
					   );
}

void pngwriter::flood_fill(int xstart, int ystart, double fill_red, double fill_green, double fill_blue) {
	flood_fill_internal(xstart,  ystart,  this->dread(xstart,ystart,1),this->dread(xstart,ystart,2),this->dread(xstart,ystart,3),   fill_red,  fill_green, fill_blue);
}

//int version
void pngwriter::flood_fill(int xstart, int ystart, int fill_red, int fill_green, int fill_blue) {
	this->flood_fill(xstart,  ystart,
					 ((double)  fill_red)/65535.0,
					 ((double) fill_green)/65535.0,
					 ((double)  fill_blue)/65535.0
					);
}

void pngwriter::polygon(int* points, int number_of_points, double red, double green, double blue) {
	if((number_of_points<1)||(points ==NULL)) {
		std::cerr << " PNGwriter::polygon - ERROR **:  Number of points is zero or negative, or array is NULL." << std::endl;
		return;
	}

	for(int k=0; k< number_of_points-1; k++) {
		this->line(points[2*k],points[2*k+1],points[2*k+2],points[2*k+3], red, green, blue);
	}
}

//int version
void pngwriter::polygon(int* points, int number_of_points, int red, int green, int blue) {
	this->polygon(points, number_of_points,
				  ((double) red)/65535.0,
				  ((double) green)/65535.0,
				  ((double) blue)/65535.0
				 );
}

void pngwriter::plotCMYK(int x, int y, double cyan, double magenta, double yellow, double black) {
	/*CMYK to RGB:
	 *  -----------
	 *  red   = 255 - minimum(255,((cyan/255)    * (255 - black) + black))
	 *  green = 255 - minimum(255,((magenta/255) * (255 - black) + black))
	 *  blue  = 255 - minimum(255,((yellow/255)  * (255 - black) + black))
	 * */

	if(cyan<0.0) {
		cyan = 0.0;
	}
	if(magenta<0.0) {
		magenta = 0.0;
	}
	if(yellow<0.0) {
		yellow = 0.0;
	}
	if(black<0.0) {
		black = 0.0;
	}

	if(cyan>1.0) {
		cyan = 1.0;
	}
	if(magenta>1.0) {
		magenta = 1.0;
	}
	if(yellow>1.0) {
		yellow = 1.0;
	}
	if(black>1.0) {
		black = 1.0;
	}

	double  red, green, blue, minr, ming, minb, iblack;

	iblack = 1.0 - black;

	minr = 1.0;
	ming = 1.0;
	minb = 1.0;

	if((cyan*iblack + black)<1.0) {
		minr = cyan*iblack + black;
	}

	if((magenta*iblack + black)<1.0) {
		ming = magenta*iblack + black;
	}

	if((yellow*iblack + black)<1.0) {
		minb = yellow*iblack + black;
	}

	red = 1.0 - minr;
	green = 1.0 - ming;
	blue = 1.0 - minb;

	this->plot(x,y,red, green, blue);

}

//int version
void pngwriter::plotCMYK(int x, int y, int cyan, int magenta, int yellow, int black) {
	this->plotCMYK(x, y,
				   ((double) cyan)/65535.0,
				   ((double) magenta)/65535.0,
				   ((double) yellow)/65535.0,
				   ((double) black)/65535.0
				  );
}

double pngwriter::dreadCMYK(int x, int y, int colour) {
	/*
	 * Black   = minimum(1-Red,1-Green,1-Blue)
	 *     Cyan    = (1-Red-Black)/(1-Black)
	 *     Magenta = (1-Green-Black)/(1-Black)
	 *     Yellow  = (1-Blue-Black)/(1-Black)
	 *
	 * */
	if((colour !=1)&&(colour !=2)&&(colour !=3)&&(colour !=4)) {
		std::cerr << " PNGwriter::dreadCMYK - WARNING **: Invalid argument: should be 1, 2, 3 or 4, is " << colour << std::endl;
		return 0;
	}

	double black, red, green, blue, ired, igreen, iblue, iblack;
	//add error detection here
	// not much to detect, really
	red = this->dread(x, y, 1);
	green = this->dread(x, y, 2);
	blue = this->dread(x, y, 3);

	ired = 1.0 - red;
	igreen = 1.0 - green;
	iblue = 1.0 - blue;

	black = ired;

	//black is the mimimum of inverse RGB colours, and if they are all equal, it is the inverse of red.
	if((igreen<ired)&&(igreen<iblue)) {
		black = igreen;
	}

	if((iblue<igreen)&&(iblue<ired)) {
		black = iblue;
	}

	iblack = 1.0 - black;

	if(colour == 1) {
		return ((ired-black)/(iblack));
	}

	if(colour == 2) {
		return ((igreen-black)/(iblack));
	}

	if(colour == 3) {
		return ((iblue-black)/(iblack));
	}

	if(colour == 4) {
		return black;
	}

	return 0.0;
}

int pngwriter::readCMYK(int x, int y, int colour) {
	/*
	 * Black   = minimum(1-Red,1-Green,1-Blue)
	 *     Cyan    = (1-Red-Black)/(1-Black)
	 *     Magenta = (1-Green-Black)/(1-Black)
	 *     Yellow  = (1-Blue-Black)/(1-Black)
	 *
	 * */
	if((colour !=1)&&(colour !=2)&&(colour !=3)&&(colour !=4)) {
		std::cerr << " PNGwriter::readCMYK - WARNING **: Invalid argument: should be 1, 2, 3 or 4, is " << colour << std::endl;
		return 0;
	}

	double black, red, green, blue, ired, igreen, iblue, iblack;
	//add error detection here
	// not much to detect, really
	red = this->dread(x, y, 1);
	green = this->dread(x, y, 2);
	blue = this->dread(x, y, 3);

	ired = 1.0 - red;
	igreen = 1.0 - green;
	iblue = 1.0 - blue;

	black = ired;

	//black is the mimimum of inverse RGB colours, and if they are all equal, it is the inverse of red.
	if((igreen<ired)&&(igreen<iblue)) {
		black = igreen;
	}

	if((iblue<igreen)&&(iblue<ired)) {
		black = iblue;
	}

	iblack = 1.0 - black;

	if(colour == 1) {
		return (int)(((ired-black)/(iblack))*65535);
	}

	if(colour == 2) {
		return (int)(((igreen-black)/(iblack))*65535);
	}

	if(colour == 3) {
		return (int)(((iblue-black)/(iblack))*65535);
	}

	if(colour == 4) {
		return (int)((black)*65535);
	}

	return 0;

}

void pngwriter::scale_k(double k) {
	if(k <= 0.0) {
		std::cerr << " PNGwriter::scale_k - ERROR **:  scale_k() called with negative or zero scale factor. Was: " << k << "." << std::endl;
	}

	// Calculate the new scaled height and width
	int scaledh, scaledw;
	scaledw = (int) ceil(k*width_);
	scaledh = (int) ceil(k*height_);

	// Create image storage.
	pngwriter temp(scaledw,scaledh,0,"temp");

	int red, green, blue;

	double spacingx = ((double)width_)/(2*scaledw);
	double spacingy = ((double)height_)/(2*scaledh);

	double readx, ready;

	for(int x = 1; x<= scaledw; x++) {
		for(int y = 1; y <= scaledh; y++) {
			readx = (2*x-1)*spacingx;
			ready = (2*y-1)*spacingy;
			red = this->bilinear_interpolation_read(readx, ready, 1);
			green = this->bilinear_interpolation_read(readx, ready, 2);
			blue = this->bilinear_interpolation_read(readx, ready, 3);
			temp.plot(x, y, red, green, blue);

		}
	}

	// From here on, the process is the same for all scale functions.
	//Get data out of temp and into this's storage.

	//Resize this instance
	// Delete current storage.
	for(int jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
	free(graph_);

	//New image will have bit depth 16, regardless of original bit depth.
	bit_depth_ = 16;

	// New width and height will be the scaled width and height
	width_ = scaledw;
	height_ = scaledh;
	backgroundcolour_ = 0;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_k - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(int kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::scale_k - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_k - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	//This instance now has a new, resized storage space.

	//Copy the temp date into this's storage.
	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = temp.graph_[vhhh][tempindex];
			graph_[vhhh][tempindex+1] = temp.graph_[vhhh][tempindex+1];
			graph_[vhhh][tempindex+2] = temp.graph_[vhhh][tempindex+2];
			graph_[vhhh][tempindex+3] = temp.graph_[vhhh][tempindex+3];
			graph_[vhhh][tempindex+4] = temp.graph_[vhhh][tempindex+4];
			graph_[vhhh][tempindex+5] = temp.graph_[vhhh][tempindex+5];
		}
	}

	// this should now contain the new, scaled image data.
	//
}

void pngwriter::scale_kxky(double kx, double ky) {
	if((kx <= 0.0)||(ky <= 0.0)) {
		std::cerr << " PNGwriter::scale_kxky - ERROR **:  scale_kxky() called with negative or zero scale factor. Was: " << kx << ", " << ky << "." << std::endl;
	}

	int scaledh, scaledw;
	scaledw = (int) ceil(kx*width_);
	scaledh = (int) ceil(ky*height_);

	pngwriter temp(scaledw, scaledh, 0, "temp");

	int red, green, blue;

	double spacingx = ((double)width_)/(2*scaledw);
	double spacingy = ((double)height_)/(2*scaledh);

	double readx, ready;

	for(int x = 1; x<= scaledw; x++) {
		for(int y = 1; y <= scaledh; y++) {
			readx = (2*x-1)*spacingx;
			ready = (2*y-1)*spacingy;
			red = this->bilinear_interpolation_read(readx, ready, 1);
			green = this->bilinear_interpolation_read(readx, ready, 2);
			blue = this->bilinear_interpolation_read(readx, ready, 3);
			temp.plot(x, y, red, green, blue);

		}
	}
	// From here on, the process is the same for all scale functions.
	//Get data out of temp and into this's storage.

	//Resize this instance
	// Delete current storage.
	for(int jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
	free(graph_);

	//New image will have bit depth 16, regardless of original bit depth.
	bit_depth_ = 16;

	// New width and height will be the scaled width and height
	width_ = scaledw;
	height_ = scaledh;
	backgroundcolour_ = 0;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_kxky - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(int kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::scale_kxky - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_kxky - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	//This instance now has a new, resized storage space.

	//Copy the temp date into this's storage.
	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = temp.graph_[vhhh][tempindex];
			graph_[vhhh][tempindex+1] = temp.graph_[vhhh][tempindex+1];
			graph_[vhhh][tempindex+2] = temp.graph_[vhhh][tempindex+2];
			graph_[vhhh][tempindex+3] = temp.graph_[vhhh][tempindex+3];
			graph_[vhhh][tempindex+4] = temp.graph_[vhhh][tempindex+4];
			graph_[vhhh][tempindex+5] = temp.graph_[vhhh][tempindex+5];
		}
	}

	// this should now contain the new, scaled image data.
	//
	//
}

void pngwriter::scale_wh(int finalwidth, int finalheight) {
	if((finalwidth <= 0)||(finalheight <= 0)) {
		std::cerr << " PNGwriter::scale_wh - ERROR **: Negative or zero final width or height not allowed." << std::endl;
	}

	double kx;
	double ky;

	kx = ((double)finalwidth)/((double)width_);
	ky = ((double)finalheight)/((double)height_);

	pngwriter temp(finalwidth, finalheight, 0, "temp");

	int red, green, blue;

	double spacingx = ((double)width_)/(2*finalwidth);
	double spacingy = ((double)height_)/(2*finalheight);

	double readx, ready;

	for(int x = 1; x<= finalwidth; x++) {
		for(int y = 1; y <= finalheight; y++) {
			readx = (2*x-1)*spacingx;
			ready = (2*y-1)*spacingy;
			red = this->bilinear_interpolation_read(readx, ready, 1);
			green = this->bilinear_interpolation_read(readx, ready, 2);
			blue = this->bilinear_interpolation_read(readx, ready, 3);
			temp.plot(x, y, red, green, blue);

		}
	}

	// From here on, the process is the same for all scale functions.
	//Get data out of temp and into this's storage.

	//Resize this instance
	// Delete current storage.
	for(int jjj = 0; jjj < height_; jjj++) free(graph_[jjj]);
	free(graph_);

	//New image will have bit depth 16, regardless of original bit depth.
	bit_depth_ = 16;

	// New width and height will be the scaled width and height
	width_ = finalwidth;
	height_ = finalheight;
	backgroundcolour_ = 0;

	graph_ = (png_bytepp)malloc(height_ * sizeof(png_bytep));
	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_wh - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	for(int kkkk = 0; kkkk < height_; kkkk++) {
		graph_[kkkk] = (png_bytep)malloc(6*width_ * sizeof(png_byte));
		if(graph_[kkkk] == NULL) {
			std::cerr << " PNGwriter::scale_wh - ERROR **:  Not able to allocate memory for image." << std::endl;
		}
	}

	if(graph_ == NULL) {
		std::cerr << " PNGwriter::scale_wh - ERROR **:  Not able to allocate memory for image." << std::endl;
	}

	//This instance now has a new, resized storage space.

	//Copy the temp date into this's storage.
	int tempindex;
	for(int hhh = 0; hhh<width_; hhh++) {
		for(int vhhh = 0; vhhh<height_; vhhh++) {
			tempindex=6*hhh;
			graph_[vhhh][tempindex] = temp.graph_[vhhh][tempindex];
			graph_[vhhh][tempindex+1] = temp.graph_[vhhh][tempindex+1];
			graph_[vhhh][tempindex+2] = temp.graph_[vhhh][tempindex+2];
			graph_[vhhh][tempindex+3] = temp.graph_[vhhh][tempindex+3];
			graph_[vhhh][tempindex+4] = temp.graph_[vhhh][tempindex+4];
			graph_[vhhh][tempindex+5] = temp.graph_[vhhh][tempindex+5];
		}
	}

	// this should now contain the new, scaled image data.
	//
	//
}

// Blended functions
//
void pngwriter::plotHSV_blend(int x, int y, double opacity, double hue, double saturation, double value) {
	double red,green,blue;
	double* redp;
	double* greenp;
	double* bluep;

	redp = &red;
	greenp = &green;
	bluep = &blue;

	HSVtoRGB(redp,greenp,bluep,hue,saturation,value);
	plot_blend(x,y,opacity, red,green,blue);

}

void pngwriter::plotHSV_blend(int x, int y, double opacity, int hue, int saturation, int value) {
	plotHSV_blend(x, y, opacity, double(hue)/65535.0, double(saturation)/65535.0,  double(value)/65535.0);
}

void pngwriter::line_blend(int xfrom, int yfrom, int xto, int yto,  double opacity, int red, int green,int  blue) {
	//  Bresenham Algorithm.
	//
	int dy = yto - yfrom;
	int dx = xto - xfrom;
	int stepx, stepy;

	if(dy < 0) {
		dy = -dy;
		stepy = -1;
	} else {
		stepy = 1;
	}

	if(dx < 0) {
		dx = -dx;
		stepx = -1;
	} else {
		stepx = 1;
	}
	dy <<= 1;     // dy is now 2*dy
	dx <<= 1;     // dx is now 2*dx

	this->plot_blend(xfrom,yfrom,opacity, red,green,blue);

	if(dx > dy) {
		int fraction = dy - (dx >> 1);

		while(xfrom != xto) {
			if(fraction >= 0) {
				yfrom += stepy;
				fraction -= dx;
			}
			xfrom += stepx;
			fraction += dy;
			this->plot_blend(xfrom,yfrom,opacity, red,green,blue);
		}
	} else {
		int fraction = dx - (dy >> 1);
		while(yfrom != yto) {
			if(fraction >= 0) {
				xfrom += stepx;
				fraction -= dy;
			}
			yfrom += stepy;
			fraction += dx;
			this->plot_blend(xfrom,yfrom, opacity, red,green,blue);
		}
	}

}

void pngwriter::line_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue) {
	this->line_blend(xfrom,
					 yfrom,
					 xto,
					 yto,
					 opacity,
					 int (red*65535),
					 int (green*65535),
					 int (blue*65535)
					);

}

void pngwriter::square_blend(int xfrom, int yfrom, int xto, int yto, double opacity, int red, int green,int  blue) {
	this->line_blend(xfrom, yfrom, xfrom, yto, opacity, red, green, blue);
	this->line_blend(xto, yfrom, xto, yto, opacity, red, green, blue);
	this->line_blend(xfrom, yfrom, xto, yfrom, opacity, red, green, blue);
	this->line_blend(xfrom, yto, xto, yto, opacity,  red, green, blue);
}

void pngwriter::square_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue) {
	this->square_blend(xfrom,  yfrom,  xto,  yto, opacity, int(red*65535), int(green*65535), int(blue*65535));
}

void pngwriter::filledsquare_blend(int xfrom, int yfrom, int xto, int yto, double opacity, int red, int green,int  blue) {
	for(int caca = xfrom; caca <xto+1; caca++) {
		this->line_blend(caca, yfrom, caca, yto, opacity, red, green, blue);
	}

}

void pngwriter::filledsquare_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue) {
	this->filledsquare_blend(xfrom,  yfrom,  xto,  yto, opacity, int(red*65535), int(green*65535), int(blue*65535));
}

void pngwriter::circle_aux_blend(int xcentre, int ycentre, int x, int y, double opacity, int red, int green, int blue) {
	if(x == 0) {
		this->plot_blend(xcentre, ycentre + y, opacity, red, green, blue);
		this->plot_blend(xcentre, ycentre - y, opacity, red, green, blue);
		this->plot_blend(xcentre + y, ycentre, opacity, red, green, blue);
		this->plot_blend(xcentre - y, ycentre, opacity, red, green, blue);
	} else if(x == y) {
		this->plot_blend(xcentre + x, ycentre + y, opacity, red, green, blue);
		this->plot_blend(xcentre - x, ycentre + y, opacity, red, green, blue);
		this->plot_blend(xcentre + x, ycentre - y, opacity, red, green, blue);
		this->plot_blend(xcentre - x, ycentre - y, opacity, red, green, blue);
	} else if(x < y) {
		this->plot_blend(xcentre + x, ycentre + y, opacity, red, green, blue);
		this->plot_blend(xcentre - x, ycentre + y, opacity, red, green, blue);
		this->plot_blend(xcentre + x, ycentre - y, opacity, red, green, blue);
		this->plot_blend(xcentre - x, ycentre - y, opacity, red, green, blue);
		this->plot_blend(xcentre + y, ycentre + x, opacity, red, green, blue);
		this->plot_blend(xcentre - y, ycentre + x, opacity, red, green, blue);
		this->plot_blend(xcentre + y, ycentre - x, opacity, red, green, blue);
		this->plot_blend(xcentre - y, ycentre - x, opacity, red, green, blue);
	}

}
//

void pngwriter::circle_blend(int xcentre, int ycentre, int radius, double opacity, int red, int green, int blue) {
	int x = 0;
	int y = radius;
	int p = (5 - radius*4)/4;

	circle_aux_blend(xcentre, ycentre, x, y, opacity, red, green, blue);
	while(x < y) {
		x++;
		if(p < 0) {
			p += 2*x+1;
		} else {
			y--;
			p += 2*(x-y)+1;
		}
		circle_aux_blend(xcentre, ycentre, x, y, opacity, red, green, blue);
	}

}

void pngwriter::circle_blend(int xcentre, int ycentre, int radius, double opacity, double red, double green, double blue) {
	this->circle_blend(xcentre,ycentre,radius, opacity,  int(red*65535), int(green*65535), int(blue*65535));
}

void pngwriter::filledcircle_blend(int xcentre, int ycentre, int radius, double opacity, int red, int green, int blue) {
	for(int jjj = ycentre-radius; jjj< ycentre+radius+1; jjj++) {
		this->line_blend(xcentre - int(sqrt((double)(radius*radius) - (-ycentre + jjj)*(-ycentre + jjj))), jjj,
						 xcentre + int(sqrt((double)(radius*radius) - (-ycentre + jjj)*(-ycentre + jjj))),jjj, opacity, red,green,blue);
	}

}

void pngwriter::filledcircle_blend(int xcentre, int ycentre, int radius, double opacity, double red, double green, double blue) {
	this->filledcircle_blend(xcentre, ycentre,  radius, opacity, int(red*65535), int(green*65535), int(blue*65535));
}

void pngwriter::bezier_blend(int startPtX, int startPtY,
							 int startControlX, int startControlY,
							 int endPtX, int endPtY,
							 int endControlX, int endControlY,
							 double opacity,
							 double red, double green, double blue) {

	double cx = 3.0*(startControlX - startPtX);
	double bx = 3.0*(endControlX - startControlX) - cx;
	double ax = double(endPtX - startPtX - cx - bx);

	double cy = 3.0*(startControlY - startPtY);
	double by = 3.0*(endControlY - startControlY) - cy;
	double ay = double(endPtY - startPtY - cy - by);

	double x,y,newx,newy;
	x = startPtX;
	y = startPtY;

	for(double t = 0.0; t<=1.005; t += 0.005) {
		newx = startPtX + t*(double(cx) + t*(double(bx) + t*(double(ax))));
		newy = startPtY + t*(double(cy) + t*(double(by) + t*(double(ay))));
		this->line_blend(int(x),int(y),int(newx),int(newy),opacity, red,green,blue);
		x = newx;
		y = newy;
	}
}

void pngwriter::bezier_blend(int startPtX, int startPtY,
							 int startControlX, int startControlY,
							 int endPtX, int endPtY,
							 int endControlX, int endControlY,
							 double opacity,
							 int red, int green, int blue) {
	this->bezier_blend(startPtX,  startPtY,
					   startControlX, startControlY,
					   endPtX, endPtY,
					   endControlX,  endControlY,
					   opacity,
					   double(red)/65535.0,  double(green)/65535.0,  double(blue)/65535.0);

}

/////////////////////////////
#ifndef NO_FREETYPE

// Freetype-based text rendering functions.
///////////////////////////////////////////
void pngwriter::plot_text_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity, double red, double green, double blue) {
	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(cos(angle)*0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(-sin(angle)*0x10000);   /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(sin(angle)*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(cos(angle)*0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = x_start*64 ;
	pen.y = (int)(y_start/64.0);

	/*Count the length of the string */
	int num_chars = strlen(text);

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::plot_text_blend - ERROR **: FreeType: Could not init Library."<< std::endl; return;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::plot_text_blend - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return; } else if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not find or load font file."<< std::endl; return; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(((double) delta.x)*cos(angle));
			pen.y += (int)(((double) delta.x)*(sin(angle)));
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::plot_text_blend - ERROR **: FreeType: Set char size error." << std::endl; return;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::plot_text_blend - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return;}

		/* Convert to an anti-aliased bitmap */
		//	error = FT_Render_Glyph( face->glyph, FT_RENDER_MODE_NORMAL );
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::plot_text_blend - ERROR **: FreeType: Render glyph error." << std::endl; return;}

		/* Now, draw to our target surface */
		my_draw_bitmap_blend(&slot->bitmap,
							 slot->bitmap_left,
							 y_start + slot->bitmap_top,
							 opacity,
							 red,
							 green,
							 blue);

		/* Advance to the next position */
		pen.x += slot->advance.x;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}

	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);
}

void pngwriter::plot_text_utf8_blend(char* face_path, int fontsize, int x_start, int y_start, double angle,  char* text, double opacity, double red, double green, double blue) {
	FT_Library  library;
	FT_Face     face;
	FT_Matrix   matrix;      // transformation matrix
	FT_Vector   pen;

	FT_UInt glyph_index;
	FT_Error error;

	FT_Bool use_kerning;
	FT_UInt previous = 0;

	/* Set up transformation Matrix */
	matrix.xx = (FT_Fixed)(cos(angle)*0x10000);    /* It would make more sense to do this (below), but, bizzarely, */
	matrix.xy = (FT_Fixed)(-sin(angle)*0x10000);   /* if one does, FT_Load_Glyph fails consistently.               */
	matrix.yx = (FT_Fixed)(sin(angle)*0x10000);   //   matrix.yx = - matrix.xy;
	matrix.yy = (FT_Fixed)(cos(angle)*0x10000);   //   matrix.yy = matrix.xx;

	/* Place starting coordinates in adequate form. */
	pen.x = x_start*64 ;
	pen.y = (int)(y_start/64.0);

	/*Count the length of the string */
	int num_bytes=0;
	while(text[num_bytes]!=0) {
		num_bytes++;
	}

	/*
	   std::cout << "Num bytes is: "<< num_bytes << std::endl;
	   */

	//The array of ucs4 glyph indexes, which will by at most the number of bytes in the utf-8 file.
	long* ucs4text;
	ucs4text = new long[num_bytes+1];

	unsigned char u,v,w,x,y,z;

	int num_chars=0;

	long iii=0;

	while(iii<num_bytes) {
		z = text[iii];

		if(z<=127) {
			ucs4text[num_chars] = z;
		}

		if((192<=z)&&(z<=223)) {
			iii++;
			y = text[iii];
			ucs4text[num_chars] = (z-192)*64 + (y -128);
		}

		if((224<=z)&&(z<=239)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			ucs4text[num_chars] = (z-224)*4096 + (y -128)*64 + (x-128);
		}

		if((240<=z)&&(z<=247)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			ucs4text[num_chars] = (z-240)*262144 + (y -128)*4096 + (x-128)*64 + (w-128);
		}

		if((248<=z)&&(z<=251)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			ucs4text[num_chars] = (z-248)*16777216 + (y -128)*262144 + (x-128)*4096 + (w-128)*64 +(v-128);
		}

		if((252==z)||(z==253)) {
			iii++;
			y = text[iii];
			iii++;
			x = text[iii];
			iii++;
			w = text[iii];
			iii++;
			v = text[iii];
			u = text[iii];
			ucs4text[num_chars] = (z-252)*1073741824 + (y -128)*16777216   + (x-128)*262144 + (w-128)*4096 +(v-128)*64 + (u-128);
		}

		if((z==254)||(z==255)) {
			std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: Problem with character: invalid UTF-8 data."<< std::endl;
		}
		// std::cerr << "\nProblem at " << iii << ".\n";
		//
		iii++;
		num_chars++;
	}

	// num_chars now contains the number of characters in the string.
	/*
	std::cout << "Num chars is: "<< num_chars << std::endl;
	*/

	/* Initialize FT Library object */
	error = FT_Init_FreeType(&library);
	if(error) { std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: FreeType: Could not init Library."<< std::endl; return;}

	/* Initialize FT face object */
	error = FT_New_Face(library,face_path,0,&face);
	if(error == FT_Err_Unknown_File_Format) { std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: FreeType: Font was opened, but type not supported."<< std::endl; return; } else if(error) { std::cerr << " PNGwriter::plot_text - ERROR **: FreeType: Could not find or load font file."<< std::endl; return; }

	/* Set the Char size */
	error = FT_Set_Char_Size(face,           /* handle to face object           */
							 0,             /* char_width in 1/64th of points  */
							 fontsize*64,   /* char_height in 1/64th of points */
							 100,           /* horizontal device resolution    */
							 100);          /* vertical device resolution      */

	/* A way of accesing the glyph directly */
	FT_GlyphSlot  slot = face->glyph;  // a small shortcut

	/* Does the font file support kerning? */
	use_kerning = FT_HAS_KERNING(face);

	int n;
	for(n = 0; n < num_chars; n++) {
		/* Convert character code to glyph index */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Retrieve kerning distance and move pen position */
		if(use_kerning && previous&& glyph_index) {
			FT_Vector  delta;
			FT_Get_Kerning(face,
						   previous,
						   glyph_index,
						   ft_kerning_default, //FT_KERNING_DEFAULT,
						   &delta);

			/* Transform this kerning distance into rotated space */
			pen.x += (int)(((double) delta.x)*cos(angle));
			pen.y += (int)(((double) delta.x)*(sin(angle)));
		}

		/* Set transform */
		FT_Set_Transform(face, &matrix, &pen);

		/*set char size*/

		if(error) { std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: FreeType: Set char size error." << std::endl; return;};

		/* Retrieve glyph index from character code */
		glyph_index = FT_Get_Char_Index(face, ucs4text[n]);

		/* Load glyph image into the slot (erase previous one) */
		error = FT_Load_Glyph(face, glyph_index, FT_LOAD_DEFAULT);
		if(error) { std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: FreeType: Could not load glyph (in loop). (FreeType error "<< std::hex << error <<")." << std::endl; return;}

		/* Convert to an anti-aliased bitmap */
		error = FT_Render_Glyph(face->glyph, ft_render_mode_normal);
		if(error) { std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **: FreeType: Render glyph error." << std::endl; return;}

		/* Now, draw to our target surface */
		my_draw_bitmap_blend(&slot->bitmap,
							 slot->bitmap_left,
							 y_start + slot->bitmap_top,
							 opacity,
							 red,
							 green,
							 blue);

		/* Advance to the next position */
		pen.x += slot->advance.x;
		pen.y += slot->advance.y;

		/* record current glyph index */
		previous = glyph_index;
	}

	/* Free the face and the library objects */
	FT_Done_Face(face);
	FT_Done_FreeType(library);

	delete[] ucs4text;
}

void pngwriter::plot_text_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity, int red, int green, int blue) {
	plot_text_blend(face_path, fontsize, x_start, y_start,  angle,  text, opacity, ((double) red)/65535.0, ((double) green)/65535.0, ((double) blue)/65535.0);
}

void pngwriter::plot_text_utf8_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity,  int red, int green, int blue) {
	plot_text_utf8_blend(face_path, fontsize, x_start, y_start,  angle,  text, opacity, ((double) red)/65535.0, ((double) green)/65535.0, ((double) blue)/65535.0);
}

void pngwriter::my_draw_bitmap_blend(FT_Bitmap* bitmap, int x, int y, double opacity, double red, double green, double blue) {
	double temp;
	for(int j=1; j<bitmap->rows+1; j++) {
		for(int i=1; i< bitmap->width + 1; i++) {
			temp = (double)(bitmap->buffer[(j-1)*bitmap->width + (i-1)])/255.0;

			if(temp) {
				this->plot_blend(x + i,
								 y  - j,
								 opacity,
								 temp*red + (1-temp)*(this->dread(x+i,y-j,1)),
								 temp*green + (1-temp)*(this->dread(x+i,y-j,2)),
								 temp*blue + (1-temp)*(this->dread(x+i,y-j,3))
								);
			}
		}
	}
}

#endif
#ifdef NO_FREETYPE

void pngwriter::plot_text_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity, int red, int green, int blue) {
	std::cerr << " PNGwriter::plot_text_blend - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

void pngwriter::plot_text_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity,  double red, double green, double blue) {
	std::cerr << " PNGwriter::plot_text_blend - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;

}

void pngwriter::plot_text_utf8_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity,  int red, int green, int blue) {
	std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

void pngwriter::plot_text_utf8_blend(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double opacity, double red, double green, double blue) {
	std::cerr << " PNGwriter::plot_text_utf8_blend - ERROR **:  PNGwriter was compiled without Freetype support! Recompile PNGwriter with Freetype support (once you have Freetype installed, that is. Websites: www.freetype.org and pngwriter.sourceforge.net)." << std::endl;
	return;
}

#endif

///////////////////////////

void pngwriter::boundary_fill_blend(int xstart, int ystart, double opacity, double boundary_red,double boundary_green,double boundary_blue,double fill_red, double fill_green, double fill_blue) {
	if((
				(this->dread(xstart,ystart,1) != boundary_red) ||
				(this->dread(xstart,ystart,2) != boundary_green) ||
				(this->dread(xstart,ystart,3) != boundary_blue)
			)
			&&
			(
				(this->dread(xstart,ystart,1) != fill_red) ||
				(this->dread(xstart,ystart,2) != fill_green) ||
				(this->dread(xstart,ystart,3) != fill_blue)
			)
			&&
			(xstart >0)&&(xstart <= width_)&&(ystart >0)&&(ystart <= height_)
	  ) {
		this->plot_blend(xstart, ystart, opacity,  fill_red, fill_green, fill_blue);
		boundary_fill_blend(xstart+1,  ystart, opacity,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill_blend(xstart,  ystart+1, opacity,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill_blend(xstart,  ystart-1, opacity,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
		boundary_fill_blend(xstart-1,  ystart, opacity,  boundary_red, boundary_green, boundary_blue, fill_red,  fill_green,  fill_blue) ;
	}
}

//no int version needed
void pngwriter::flood_fill_internal_blend(int xstart, int ystart, double opacity,  double start_red, double start_green, double start_blue, double fill_red, double fill_green, double fill_blue) {
	if((
				(this->dread(xstart,ystart,1) == start_red) &&
				(this->dread(xstart,ystart,2) == start_green) &&
				(this->dread(xstart,ystart,3) == start_blue)
			)
			&&
			(
				(this->dread(xstart,ystart,1) != fill_red) ||
				(this->dread(xstart,ystart,2) != fill_green) ||
				(this->dread(xstart,ystart,3) != fill_blue)
			)
			&&
			(xstart >0)&&(xstart <= width_)&&(ystart >0)&&(ystart <= height_)
	  ) {
		this->plot_blend(xstart, ystart, opacity, fill_red, fill_green, fill_blue);
		flood_fill_internal_blend(xstart+1,  ystart, opacity,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal_blend(xstart-1,  ystart,opacity,   start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal_blend(xstart,  ystart+1, opacity,  start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
		flood_fill_internal_blend(xstart,  ystart-1, opacity,  start_red,  start_green,  start_blue,  fill_red,  fill_green,  fill_blue);
	}

}

//int version
void pngwriter::boundary_fill_blend(int xstart, int ystart, double opacity, int boundary_red,int boundary_green,int boundary_blue,int fill_red, int fill_green, int fill_blue) {

	this->boundary_fill_blend(xstart, ystart,
							  opacity,
							  ((double) boundary_red)/65535.0,
							  ((double) boundary_green)/65535.0,
							  ((double) boundary_blue)/65535.0,
							  ((double) fill_red)/65535.0,
							  ((double) fill_green)/65535.0,
							  ((double) fill_blue)/65535.0
							 );
}

void pngwriter::flood_fill_blend(int xstart, int ystart, double opacity, double fill_red, double fill_green, double fill_blue) {
	flood_fill_internal_blend(xstart,  ystart, opacity,  this->dread(xstart,ystart,1),this->dread(xstart,ystart,2),this->dread(xstart,ystart,3),   fill_red,  fill_green, fill_blue);
}

//int version
void pngwriter::flood_fill_blend(int xstart, int ystart, double opacity, int fill_red, int fill_green, int fill_blue) {
	this->flood_fill_blend(xstart,  ystart,
						   opacity,
						   ((double)  fill_red)/65535.0,
						   ((double) fill_green)/65535.0,
						   ((double)  fill_blue)/65535.0
						  );
}

void pngwriter::polygon_blend(int* points, int number_of_points, double opacity,  double red, double green, double blue) {
	if((number_of_points<1)||(points ==NULL)) {
		std::cerr << " PNGwriter::polygon_blend - ERROR **:  Number of points is zero or negative, or array is NULL." << std::endl;
		return;
	}

	for(int k=0; k< number_of_points-1; k++) {
		this->line_blend(points[2*k],points[2*k+1],points[2*k+2],points[2*k+3], opacity,  red, green, blue);
	}
}

//int version
void pngwriter::polygon_blend(int* points, int number_of_points, double opacity, int red, int green, int blue) {
	this->polygon_blend(points, number_of_points,
						opacity,
						((double) red)/65535.0,
						((double) green)/65535.0,
						((double) blue)/65535.0
					   );
}

void pngwriter::plotCMYK_blend(int x, int y, double opacity, double cyan, double magenta, double yellow, double black) {
	/*CMYK to RGB:
	 *  -----------
	 *  red   = 255 - minimum(255,((cyan/255)    * (255 - black) + black))
	 *  green = 255 - minimum(255,((magenta/255) * (255 - black) + black))
	 *  blue  = 255 - minimum(255,((yellow/255)  * (255 - black) + black))
	 * */

	if(cyan<0.0) {
		cyan = 0.0;
	}
	if(magenta<0.0) {
		magenta = 0.0;
	}
	if(yellow<0.0) {
		yellow = 0.0;
	}
	if(black<0.0) {
		black = 0.0;
	}

	if(cyan>1.0) {
		cyan = 1.0;
	}
	if(magenta>1.0) {
		magenta = 1.0;
	}
	if(yellow>1.0) {
		yellow = 1.0;
	}
	if(black>1.0) {
		black = 1.0;
	}

	double  red, green, blue, minr, ming, minb, iblack;

	iblack = 1.0 - black;

	minr = 1.0;
	ming = 1.0;
	minb = 1.0;

	if((cyan*iblack + black)<1.0) {
		minr = cyan*iblack + black;
	}

	if((magenta*iblack + black)<1.0) {
		ming = magenta*iblack + black;
	}

	if((yellow*iblack + black)<1.0) {
		minb = yellow*iblack + black;
	}

	red = 1.0 - minr;
	green = 1.0 - ming;
	blue = 1.0 - minb;

	this->plot_blend(x,y,opacity, red, green, blue);

}

//int version
void pngwriter::plotCMYK_blend(int x, int y, double opacity, int cyan, int magenta, int yellow, int black) {
	this->plotCMYK_blend(x, y,
						 opacity,
						 ((double) cyan)/65535.0,
						 ((double) magenta)/65535.0,
						 ((double) yellow)/65535.0,
						 ((double) black)/65535.0
						);
}

void pngwriter::laplacian(double k, double offset) {

	// Create image storage.
	pngwriter temp(width_,height_,0,"temp");

	double red, green, blue;

	for(int x = 1; x <= width_; x++) {
		for(int y = 1; y <= height_; y++) {
			red =
				8.0*this->dread(x,y,1) -
				(this->dread(x+1, y-1, 1) +
				 this->dread(x,   y-1, 1) +
				 this->dread(x-1, y-1, 1) +
				 this->dread(x-1, y,   1) +
				 this->dread(x+1, y,   1) +
				 this->dread(x+1, y+1, 1) +
				 this->dread(x,   y+1, 1) +
				 this->dread(x-1, y+1, 1));

			green =
				8.0*this->dread(x,y,2) -
				(this->dread(x+1, y-1, 2) +
				 this->dread(x,   y-1, 2) +
				 this->dread(x-1, y-1, 2) +
				 this->dread(x-1, y,   2) +
				 this->dread(x+1, y,   2) +
				 this->dread(x+1, y+1, 2) +
				 this->dread(x,   y+1, 2) +
				 this->dread(x-1, y+1, 2));

			blue =
				8.0*this->dread(x,y,3) -
				(this->dread(x+1, y-1, 3) +
				 this->dread(x,   y-1, 3) +
				 this->dread(x-1, y-1, 3) +
				 this->dread(x-1, y,   3) +
				 this->dread(x+1, y,   3) +
				 this->dread(x+1, y+1, 3) +
				 this->dread(x,   y+1, 3) +
				 this->dread(x-1, y+1, 3));

			temp.plot(x,y,offset+k*red,offset+k*green,offset+k*blue);

		}
	}

	for(int xx = 1; xx <= width_; xx++) {
		for(int yy = 1; yy <= height_; yy++) {
			this->plot(xx,yy,  temp.read(xx,yy,1), temp.read(xx,yy,2), temp.read(xx,yy,3));
		}
	}
}



// drwatop(), drawbottom() and filledtriangle() were contributed by Gurkan Sengun
// ( <gurkan@linuks.mine.nu>, http://www.linuks.mine.nu/ )
void pngwriter::drawtop(long x1,long y1,long x2,long y2,long x3, int red, int green, int blue) {
	// This swaps x2 and x3
	// if(x2>x3) x2^=x3^=x2^=x3;
	if(x2>x3) {
		x2^=x3;
		x3^=x2;
		x2^=x3;
	}

	long posl = x1*256;
	long posr = posl;

	long cl=((x2-x1)*256)/(y2-y1);
	long cr=((x3-x1)*256)/(y2-y1);

	for(int y=y1; y<y2; y++) {
		this->line(posl/256, y, posr/256, y, red, green, blue);
		posl+=cl;
		posr+=cr;
	}
}

// drwatop(), drawbottom() and filledtriangle() were contributed by Gurkan Sengun
// ( <gurkan@linuks.mine.nu>, http://www.linuks.mine.nu/ )
void pngwriter::drawbottom(long x1,long y1,long x2,long x3,long y3, int red, int green, int blue) {
	//Swap x1 and x2
	//if(x1>x2) x2^=x1^=x2^=x1;
	if(x1>x2) {
		x2^=x1;
		x1^=x2;
		x2^=x1;
	}

	long posl=x1*256;
	long posr=x2*256;

	long cl=((x3-x1)*256)/(y3-y1);
	long cr=((x3-x2)*256)/(y3-y1);

	for(int y=y1; y<y3; y++) {
		this->line(posl/256, y, posr/256, y, red, green, blue);

		posl+=cl;
		posr+=cr;
	}
}

// drwatop(), drawbottom() and filledtriangle() were contributed by Gurkan Sengun
// ( <gurkan@linuks.mine.nu>, http://www.linuks.mine.nu/ )
void pngwriter::filledtriangle(int x1,int y1,int x2,int y2,int x3,int y3, int red, int green, int blue) {
	if((x1==x2 && x2==x3) || (y1==y2 && y2==y3)) return;

	if(y2<y1) {
		// x2^=x1^=x2^=x1;
		x2^=x1;
		x1^=x2;
		x2^=x1;
		// y2^=y1^=y2^=y1;
		y2^=y1;
		y1^=x2;
		y2^=y1;
	}

	if(y3<y1) {
		//x3^=x1^=x3^=x1;
		x3^=x1;
		x1^=x3;
		x3^=x1;
		//y3^=y1^=y3^=y1;
		y3^=y1;
		y1^=y3;
		y3^=y1;
	}

	if(y3<y2) {
		//x2^=x3^=x2^=x3;
		x2^=x3;
		x3^=x2;
		x2^=x3;
		//y2^=y3^=y2^=y3;
		y2^=y3;
		y3^=y2;
		y2^=y3;
	}

	if(y2==y3) {
		this->drawtop(x1, y1, x2, y2, x3, red, green, blue);
	} else {
		if(y1==y3 || y1==y2) {
			this->drawbottom(x1, y1, x2, x3, y3, red, green, blue);
		} else {
			int new_x = x1 + (int)((double)(y2-y1)*(double)(x3-x1)/(double)(y3-y1));
			this->drawtop(x1, y1, new_x, y2, x2, red, green, blue);
			this->drawbottom(x2, y2, new_x, x3, y3, red, green, blue);
		}
	}

}

//Double (bug found by Dave Wilks. Was: (int) red*65535, should have been (int) (red*65535).
void pngwriter::filledtriangle(int x1,int y1,int x2,int y2,int x3,int y3, double red, double green, double blue) {
	this->filledtriangle(x1, y1, x2, y2, x3, y3, (int)(red*65535), (int)(green*65535), (int)(blue*65535));
}

//Blend, double. (bug found by Dave Wilks. Was: (int) red*65535, should have been (int) (red*65535).
void pngwriter::filledtriangle_blend(int x1,int y1,int x2,int y2,int x3,int y3, double opacity, double red, double green, double blue) {
	this->filledtriangle_blend(x1, y1, x2, y2, x3, y3,  opacity, (int)(red*65535), (int)(green*65535), (int)(blue*65535));
}

//Blend, int
void pngwriter::filledtriangle_blend(int x1,int y1,int x2,int y2,int x3,int y3, double opacity, int red, int green, int blue) {
	if((x1==x2 && x2==x3) || (y1==y2 && y2==y3)) return;

	/*if(y2<y1)
	  {
	x2^=x1^=x2^=x1;
	y2^=y1^=y2^=y1;
	  }

	if(y3<y1)
	  {
	x3^=x1^=x3^=x1;
	y3^=y1^=y3^=y1;
	  }

	if(y3<y2)
	  {
	x2^=x3^=x2^=x3;
	y2^=y3^=y2^=y3;
	  }
	 */

	if(y2<y1) {
		// x2^=x1^=x2^=x1;
		x2^=x1;
		x1^=x2;
		x2^=x1;
		// y2^=y1^=y2^=y1;
		y2^=y1;
		y1^=x2;
		y2^=y1;
	}

	if(y3<y1) {
		//x3^=x1^=x3^=x1;
		x3^=x1;
		x1^=x3;
		x3^=x1;
		//y3^=y1^=y3^=y1;
		y3^=y1;
		y1^=y3;
		y3^=y1;
	}

	if(y3<y2) {
		//x2^=x3^=x2^=x3;
		x2^=x3;
		x3^=x2;
		x2^=x3;
		//y2^=y3^=y2^=y3;
		y2^=y3;
		y3^=y2;
		y2^=y3;
	}


	if(y2==y3) {
		this->drawtop_blend(x1, y1, x2, y2, x3, opacity, red, green, blue);
	} else {
		if(y1==y3 || y1==y2) {
			this->drawbottom_blend(x1, y1, x2, x3, y3, opacity, red, green, blue);
		} else {
			int new_x = x1 + (int)((double)(y2-y1)*(double)(x3-x1)/(double)(y3-y1));
			this->drawtop_blend(x1, y1, new_x, y2, x2, opacity,  red, green, blue);
			this->drawbottom_blend(x2, y2, new_x, x3, y3, opacity, red, green, blue);
		}
	}

}

//Blend, int
void pngwriter::drawbottom_blend(long x1,long y1,long x2,long x3,long y3, double opacity, int red, int green, int blue) {
	//Swap x1 and x2
	if(x1>x2) {
		x2^=x1;
		x1^=x2;
		x2^=x1;
	}

	long posl=x1*256;
	long posr=x2*256;

	long cl=((x3-x1)*256)/(y3-y1);
	long cr=((x3-x2)*256)/(y3-y1);

	for(int y=y1; y<y3; y++) {
		this->line_blend(posl/256, y, posr/256, y, opacity, red, green, blue);

		posl+=cl;
		posr+=cr;
	}

}

//Blend, int
void pngwriter::drawtop_blend(long x1,long y1,long x2,long y2,long x3, double opacity, int red, int green, int blue) {
	// This swaps x2 and x3
	if(x2>x3) {
		x2^=x3;
		x3^=x2;
		x2^=x3;
	}

	long posl = x1*256;
	long posr = posl;

	long cl=((x2-x1)*256)/(y2-y1);
	long cr=((x3-x1)*256)/(y2-y1);

	for(int y=y1; y<y2; y++) {
		this->line_blend(posl/256, y, posr/256, y, opacity, red, green, blue);
		posl+=cl;
		posr+=cr;
	}

}

void pngwriter::triangle(int x1, int y1, int x2, int y2, int x3, int y3, int red, int green, int blue) {
	this->line(x1, y1, x2, y2, red, green, blue);
	this->line(x2, y2, x3, y3, red, green, blue);
	this->line(x3, y3, x1, y1, red, green, blue);
}

void pngwriter::triangle(int x1, int y1, int x2, int y2, int x3, int y3, double red, double green, double blue) {

	this->line(x1, y1, x2, y2, ((int)65535*red), ((int)65535*green), ((int)65535*blue));
	this->line(x2, y2, x3, y3, ((int)65535*red), ((int)65535*green), ((int)65535*blue));
	this->line(x3, y3, x1, y1, ((int)65535*red), ((int)65535*green), ((int)65535*blue));

}





void pngwriter::arrow(int x1,int y1,int x2,int y2,int size, double head_angle, double red, double green, double blue) {

	this->line(x1, y1, x2, y2, red, green, blue);
	//   double th = 3.141592653589793 + (head_angle)*3.141592653589793/180.0;  //degrees
	double th = 3.141592653589793 + head_angle;
	double costh = cos(th);
	double sinth = sin(th);
	double t1, t2, r;
	t1 = ((x2-x1)*costh - (y2-y1)*sinth);
	t2 = ((x2-x1)*sinth + (y2-y1)*costh);
	r = sqrt(t1*t1 + t2*t2);

	double advancex  = size*t1/r;
	double advancey  = size*t2/r;
	this->line(x2, y2, int(x2 + advancex), int(y2 + advancey), red, green, blue);
	t1 = (x2-x1)*costh + (y2-y1)*sinth;
	t2 = (y2-y1)*costh - (x2-x1)*sinth;

	advancex  = size*t1/r;
	advancey  = size*t2/r;
	this->line(x2, y2, int(x2 + advancex), int(y2 + advancey), red, green, blue);
}

void pngwriter::filledarrow(int x1,int y1,int x2,int y2,int size, double head_angle, double red, double green, double blue) {
	int p1x, p2x, p3x, p1y, p2y, p3y;

	this->line(x1, y1, x2, y2, red, green, blue);
	double th = 3.141592653589793 + head_angle;
	double costh = cos(th);
	double sinth = sin(th);
	double t11, t12, t21, t22, r1, r2;
	t11 = ((x2-x1)*costh - (y2-y1)*sinth);
	t21 = ((x2-x1)*sinth + (y2-y1)*costh);
	t12 = (x2-x1)*costh + (y2-y1)*sinth;
	t22 = (y2-y1)*costh - (x2-x1)*sinth;

	r1 = sqrt(t11*t11 + t21*t21);
	r2 = sqrt(t12*t12 + t22*t22);

	double advancex1  = size*t11/r1;
	double advancey1  = size*t21/r1;
	double advancex2  = size*t12/r2;
	double advancey2  = size*t22/r2;

	p1x = x2;
	p1y = y2;

	p2x = int(x2 + advancex1);
	p2y = int(y2 + advancey1);

	p3x = int(x2 + advancex2);
	p3y = int(y2 + advancey2);


	this->filledtriangle(p1x,  p1y,  p2x,  p2y,  p3x,  p3y, red, green,  blue);

}

void pngwriter::arrow(int x1,int y1,int x2,int y2,int size, double head_angle, int red, int green, int blue) {
	this->arrow(x1, y1, x2, y2, size,  head_angle, (double(red))/65535.0, (double(green))/65535.0, (double(blue))/65535.0);
}

void pngwriter::filledarrow(int x1,int y1,int x2,int y2,int size, double head_angle, int red, int green, int blue) {
	this->filledarrow(x1, y1, x2, y2, size,  head_angle, (double(red))/65535.0, (double(green))/65535.0, (double(blue))/65535.0);
}


void pngwriter::cross(int x, int y, int xwidth, int yheight, int red, int green, int blue) {
	this->line(int(x - xwidth/2.0), y, int(x + xwidth/2.0), y, red, green, blue);
	this->line(x, int(y - yheight/2.0), x, int(y + yheight/2.0), red, green, blue);
}

void pngwriter::maltesecross(int x, int y, int xwidth, int yheight, int x_bar_height, int y_bar_width, int red, int green, int blue) {
	this->line(int(x - xwidth/2.0), y, int(x + xwidth/2.0), y, red, green, blue);
	this->line(x, int(y - yheight/2.0), x, int(y + yheight/2.0), red, green, blue);
	// Bars on ends of vertical line
	this->line(int(x - y_bar_width/2.0), int(y + yheight/2.0), int(x + y_bar_width/2.0), int(y + yheight/2.0), red, green, blue);
	this->line(int(x - y_bar_width/2.0), int(y - yheight/2.0), int(x + y_bar_width/2.0), int(y - yheight/2.0), red, green, blue);
	// Bars on ends of horizontal line.
	this->line(int(x - xwidth/2.0), int(y - x_bar_height/2.0), int(x - xwidth/2.0), int(y + x_bar_height/2.0), red, green, blue);
	this->line(int(x + xwidth/2.0), int(y - x_bar_height/2.0), int(x + xwidth/2.0), int(y + x_bar_height/2.0), red, green, blue);
}

void pngwriter::cross(int x, int y, int xwidth, int yheight, double red, double green, double blue) {
	this->cross(x, y, xwidth, yheight, int(65535*red), int(65535*green), int(65535*blue));
}

void pngwriter::maltesecross(int x, int y, int xwidth, int yheight, int x_bar_height, int y_bar_width, double red, double green, double blue) {
	this->maltesecross(x, y, xwidth, yheight, x_bar_height, y_bar_width, int(65535*red), int(65535*green), int(65535*blue));
}


void pngwriter::filleddiamond(int x, int y, int width, int height, int red, int green, int blue) {
	this->filledtriangle(int(x - width/2.0), y, x, y, x, int(y + height/2.0), red, green, blue);
	this->filledtriangle(int(x + width/2.0), y, x, y, x, int(y + height/2.0), red, green, blue);
	this->filledtriangle(int(x - width/2.0), y, x, y, x, int(y - height/2.0), red, green, blue);
	this->filledtriangle(int(x + width/2.0), y, x, y, x, int(y - height/2.0), red, green, blue);
}

void pngwriter::diamond(int x, int y, int width, int height, int red, int green, int blue) {
	this->line(int(x - width/2.0), y, x, int(y + height/2.0), red, green, blue);
	this->line(int(x + width/2.0), y, x, int(y + height/2.0), red, green, blue);
	this->line(int(x - width/2.0), y, x, int(y - height/2.0), red, green, blue);
	this->line(int(x + width/2.0), y, x, int(y - height/2.0), red, green, blue);
}


void pngwriter::filleddiamond(int x, int y, int width, int height, double red, double green, double blue) {
	this->filleddiamond(x, y,  width,  height, int(red*65535), int(green*65535), int(blue*65535));
}

void pngwriter::diamond(int x, int y, int width, int height, double red, double green, double blue) {
	this->diamond(x,  y,  width,  height, int(red*65535), int(green*65535), int(blue*65535));
}