//**********  pngwriter.h   **********************************************
//  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:             This header file 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
 *
 * */

#ifndef PNGWRITER_H
#define PNGWRITER_H 1

#define PNGWRITER_VERSION 0.54

#define NO_FREETYPE

#include <png.h>

// REMEMBER TO ADD -DNO_FREETYPE TO YOUR COMPILATION FLAGS IF PNGwriter WAS
// COMPILED WITHOUT FREETYPE SUPPORT!!!
//
// RECUERDA AGREGAR -DNO_FREETYPE A TUS OPCIONES DE COMPILACION SI PNGwriter
// FUE COMPILADO SIN SOPORTE PARA FREETYPE!!!
//
#ifndef NO_FREETYPE
#include <ft2build.h>
#include FT_FREETYPE_H
#endif



#ifdef OLD_CPP // For compatibility with older compilers.
#include <iostream.h>
#include <math.h>
#include <wchar.h>
#include <string.h>
using namespace std;
#endif // from ifdef OLD_CPP

#ifndef OLD_CPP // Default situation.
#include <iostream>
#include <cmath>
#include <cwchar>
#include <string>
#endif // from ifndef OLD_CPP


//png.h must be included before FreeType headers.
#include <stdlib.h>
#include <stdio.h>
#include <setjmp.h>




#define PNG_BYTES_TO_CHECK (4)
#define PNGWRITER_DEFAULT_COMPRESSION (0)

class pngwriter {
private:

	char* filename_;
	char* textauthor_;
	char* textdescription_;
	char* texttitle_;
	char* textsoftware_;

	bool should_free;

	int height_;
	int width_;
	int  backgroundcolour_;
	int bit_depth_;
	int rowbytes_;
	int colortype_;
	int compressionlevel_;
	bool transformation_; // Required by Mikkel's patch

	unsigned char * * graph_;
	double filegamma_;
	double screengamma_;
	void circle_aux(int xcentre, int ycentre, int x, int y, int red, int green, int blue);
	void circle_aux_blend(int xcentre, int ycentre, int x, int y, double opacity, int red, int green, int blue);
	int check_if_png(char* file_name, FILE** fp);
	int read_png_info(FILE* fp, png_structp* png_ptr, png_infop* info_ptr);
	int read_png_image(FILE* fp, png_structp png_ptr, png_infop info_ptr,
					   png_bytepp* image, png_uint_32* width, png_uint_32* height);
	void 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);
	void 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);

#ifndef NO_FREETYPE
	void my_draw_bitmap(FT_Bitmap* bitmap, int x, int y, double red, double green, double blue);
	void my_draw_bitmap_blend(FT_Bitmap* bitmap, int x, int y,double opacity,  double red, double green, double blue);
#endif

	/* 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 HSVtoRGB(double* r, double* g, double* b, double h, double s, double v);
	void RGBtoHSV(float r, float g, float b, float* h, float* s, float* v);

	/* drwatop(), drawbottom() and filledtriangle() were contributed by Gurkan Sengun
	 * ( <gurkan@linuks.mine.nu>, http://www.linuks.mine.nu/ )
	 * */
	void drawtop(long x1,long y1,long x2,long y2,long x3, int red, int green, int blue);
	void drawbottom(long x1,long y1,long x2,long x3,long y3, int red, int green, int blue);
	void drawbottom_blend(long x1,long y1,long x2,long x3,long y3, double opacity, int red, int green, int blue);
	void drawtop_blend(long x1,long y1,long x2,long y2,long x3, double opacity, int red, int green, int blue);

public:

	/* General Notes
	 * It is important to remember that all functions that accept an argument of type "const char *" will also
	 * accept "char *", this is done so you can have a changing filename (to make many PNG images in series
	 * with a different name, for example), and to allow you to use string type objects which can be easily
	 * turned into const char * (if theString is an object of type string, then it can be used as a const char *
	 * by saying theString.c_str()).
	 * It is also important to remember that whenever a function has a colour coeffiecient as its argument,
	 * that argument can be either an int from 0 to 65535 or a double from 0.0 to 1.0.
	 * It is important to make sure that you are calling the function with the type that you want.
	 * Remember that 1 is an int, while 1.0 is a double, and will thus determine what version of the function
	 * will be used. Similarly, do not make the mistake of calling for example plot(x, y, 0.0, 0.0, 65535),
	 * because
	 * there is no plot(int, int, double, double, int).
	 * Also, please note that plot() and read() (and the functions that use them internally)
	 * are protected against entering, for example, a colour coefficient that is over 65535
	 * or over 1.0. Similarly, they are protected against negative coefficients. read() will return 0
	 * when called outside the image range. This is actually useful as zero-padding should you need it.
	 * */

	/* Compilation
	 * A typical compilation would look like this:
	 *
	 * g++ my_program.cc -o my_program freetype-config --cflags \
	 *          -I/usr/local/include  -L/usr/local/lib -lpng -lpngwriter -lz -lfreetype
	 *
	 * If you did not compile PNGwriter with FreeType support, then remove the
	 * FreeType-related flags and add -DNO_FREETYPE above.
	 * */

	/* Constructor
	 * The constructor requires the width and the height of the image, the background colour for the
	 * image and the filename of the file (a pointer or simple "myfile.png"). The background colour
	 * can only be initialized to a shade of grey (once the object has been created you can do whatever
	 * you want, though), because generally one wants either a white (65535 or 1.0) or a black (0 or 0.0)
	 * background to start with.
	 * The default constructor creates a PNGwriter instance that is 250x250, white background,
	 * and filename "out.png".
	 * Tip: The filename can be given as easily as:
	 * pngwriter mypng(300, 300, 0.0, "myfile.png");
	 * Tip: If you are going to create a PNGwriter instance for reading in a file that already exists,
	 * then width and height can be 1 pixel, and the size will be automatically adjusted once you use
	 * readfromfile().
	 * */
	pngwriter();
	pngwriter(const pngwriter& rhs);
	pngwriter(int width, int height, int backgroundcolour, char* filename);
	pngwriter(int width, int height, double backgroundcolour, char* filename);
	pngwriter(int width, int height, int backgroundcolour, const char* filename);
	pngwriter(int width, int height, unsigned char * data, const char* filename);
	pngwriter(int width, int height, double backgroundcolour, const char* filename);

	/* Destructor
	 * */
	~pngwriter();

	/* Assignment Operator
	 * */
	pngwriter& operator = (const pngwriter& rhs);

	/*  Plot
	 * With this function a pixel at coordinates (x, y) can be set to the desired colour.
	 * The pixels are numbered starting from (1, 1) and go to (width, height).
	 * As with most functions in PNGwriter, it has been overloaded to accept either int arguments
	 * for the colour coefficients, or those of type double. If they are of type int,
	 * they go from 0 to 65535. If they are of type double, they go from 0.0 to 1.0.
	 * Tip: To plot using red, then specify plot(x, y, 1.0, 0.0, 0.0). To make pink,
	 * just add a constant value to all three coefficients, like this:
	 * plot(x, y, 1.0, 0.4, 0.4).
	 * Tip: If nothing is being plotted to your PNG file, make sure that you remember
	 * to close() the instance before your program is finished, and that the x and y position
	 * is actually within the bounds of your image. If either is not, then PNGwriter will
	 * not complain-- it is up to you to check for this!
	 * Tip: If you try to plot with a colour coefficient out of range, a maximum or minimum
	 * coefficient will be assumed, according to the given coefficient. For example, attempting
	 * to plot plot(x, y, 1.0,-0.2,3.7) will set the green coefficient to 0 and the red coefficient
	 * to 1.0.
	 * */
	void  plot(int x, int y, int red, int green, int blue);
	void  plot(int x, int y, double red, double green, double blue);

	/* Plot HSV
	 * With this function a pixel at coordinates (x, y) can be set to the desired colour,
	 * but with the colour coefficients given in the Hue, Saturation, Value colourspace.
	 * This has the advantage that one can determine the colour that will be plotted with
	 * only one parameter, the Hue. The colour coefficients must go from 0 to 65535 and
	 * be of type int, or be of type double and go from 0.0 to 1.0.
	 * */
	void plotHSV(int x, int y, double hue, double saturation, double value);
	void plotHSV(int x, int y, int hue, int saturation, int value);

	/* Read
	 * With this function we find out what colour the pixel (x, y) is. If "colour" is 1,
	 * it will return the red coefficient, if it is set to 2, the green one, and if
	 * it set to 3, the blue colour coefficient will be returned,
	 * and this returned value will be of type int and be between 0 and 65535.
	 * Note that if you call read() on a pixel outside the image range, the value returned
	 * will be 0.
	 * */
	int read(int x, int y, int colour);

	/* Read, Average
	 * Same as the above, only that the average of the three colour coefficients is returned.
	 */
	int read(int x, int y);

	/* dRead
	 * With this function we find out what colour the pixel (x, y) is. If "colour" is 1,
	 * it will return the red coefficient, if it is set to 2, the green one, and if
	 * it set to 3, the blue colour coefficient will be returned,
	 * and this returned value will be of type double and be between 0.0 and 1.0.
	 * Note that if you call dread() outside the image range, the value returned will be 0.0
	 * */
	double dread(int x, int y, int colour);

	/* dRead, Average
	 * Same as the above, only that the average of the three colour coefficients is returned.
	 */
	double dread(int x, int y);

	/* Read HSV
	 * With this function we find out what colour the pixel (x, y) is, but in the Hue,
	 * Saturation, Value colourspace. If "colour" is 1,
	 * it will return the Hue coefficient, if it is set to 2, the Saturation one, and if
	 * it set to 3, the Value colour coefficient will be returned, and this returned
	 * value will be of type int and be between 0 and 65535. Important: If you attempt
	 * to read the Hue of a pixel that is a shade of grey, the value returned will be
	 * nonsensical or even NaN. This is just the way the RGB -> HSV algorithm works:
	 * the Hue of grey is not defined. You might want to check whether the pixel
	 * you are reading is grey before attempting a readHSV().
	 * Tip: This is especially useful for categorizing sections of the image according
	 * to their colour.
	 * */
	int readHSV(int x, int y, int colour);

	/* dRead HSV
	 * With this function we find out what colour the pixel (x, y) is, but in the Hue,
	 * Saturation, Value colourspace. If "colour" is 1,
	 * it will return the Hue coefficient, if it is set to 2, the Saturation one, and if
	 * it set to 3, the Value colour coefficient will be returned,
	 * and this returned value will be of type double and be between 0.0 and 1.0.
	 * */
	double dreadHSV(int x, int y, int colour);

	/* Clear
	 * The whole image is set to black.
	 * */
	void clear(void);

	/* Close
	 * Close the instance of the class, and write the image to disk.
	 * Tip: If you do not call this function before your program ends, no image
	 * will be written to disk.
	 * */
	void close(void);

	/* Rename
	 * To rename the file once an instance of pngwriter has been created.
	 * Useful for assigning names to files based upon their content.
	 * Tip: This is as easy as calling pngwriter_rename("newname.png")
	 * If the argument is a long unsigned int, for example 77, the filename will be changed to
	 * 0000000077.png
	 * Tip: Use this to create sequences of images for movie generation.
	 * */
	void pngwriter_rename(char* newname);
	void pngwriter_rename(const char* newname);
	void pngwriter_rename(long unsigned int index);

	/* Figures
	 * These functions draw basic shapes. Available in both int and double versions.
	 * The line functions use the fast Bresenham algorithm. Despite the name,
	 * the square functions draw rectangles. The circle functions use a fast
	 * integer math algorithm. The filled circle functions make use of sqrt().
	 * */
	void line(int xfrom, int yfrom, int xto, int yto, int red, int green,int  blue);
	void line(int xfrom, int yfrom, int xto, int yto, double red, double green,double  blue);

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

	void square(int xfrom, int yfrom, int xto, int yto, int red, int green,int  blue);
	void square(int xfrom, int yfrom, int xto, int yto, double red, double green,double  blue);

	void filledsquare(int xfrom, int yfrom, int xto, int yto, int red, int green,int  blue);
	void filledsquare(int xfrom, int yfrom, int xto, int yto, double red, double green,double  blue);

	void circle(int xcentre, int ycentre, int radius, int red, int green, int blue);
	void circle(int xcentre, int ycentre, int radius, double red, double green, double blue);

	void filledcircle(int xcentre, int ycentre, int radius, int red, int green, int blue);
	void filledcircle(int xcentre, int ycentre, int radius, double red, double green, double blue);


	/* Read From File
	 * Open the existing PNG image, and copy it into this instance of the class. It is important to mention
	 * that PNG variants are supported. Very generally speaking, most PNG files can now be read (as of version 0.5.4),
	 * but if they have an alpha channel it will be completely stripped. If the PNG file uses GIF-style transparency
	 * (where one colour is chosen to be transparent), PNGwriter will not read the image properly, but will not
	 * complain. Also, if any ancillary chunks are included in the PNG file (chroma, filter, etc.), it will render
	 * with a slightly different tonality. For the vast majority of PNGs, this should not be an issue. Note:
	 * If you read an 8-bit PNG, the internal representation of that instance of PNGwriter will be 8-bit (PNG
	 * files of less than 8 bits will be upscaled to 8 bits). To convert it to 16-bit, just loop over all pixels,
	 * reading them into a new instance of PNGwriter. New instances of PNGwriter are 16-bit by default.
	 * */

	void readfromfile(char* name);
	void readfromfile(const char* name);

	/* Get Height
	 * When you open a PNG with readfromfile() you can find out its height with this function.
	 * */
	int getheight(void);

	/* Get Width
	 * When you open a PNG with readfromfile() you can find out its width with this function.
	 * */
	int getwidth(void);

	/* Set Compression Level
	 * Set the compression level that will be used for the image. -1 is to use the  default,
	 * 0 is none, 9 is best compression.
	 * Remember that this will affect how long it will take to close() the image. A value of 2 or 3
	 * is good enough for regular use, but for storage or transmission you might want to take the time
	 * to set it at 9.
	 * */
	void setcompressionlevel(int level);

	/* Get Bit Depth
	 * When you open a PNG with readfromfile() you can find out its bit depth with this function.
	 * Mostly for troubleshooting uses.
	 * */
	int getbitdepth(void);

	/* Get Colour Type
	 * When you open a PNG with readfromfile() you can find out its colour type (libpng categorizes
	 * different styles of image data with this number).
	 * Mostly for troubleshooting uses.
	 * */
	int getcolortype(void);

	/* Set Gamma Coeff
	 * Set the image's gamma (file gamma) coefficient. This is experimental, but use it if your image's colours seem too bright
	 * or too dark. The default value of 0.5 should be fine. The standard disclaimer about Mac and PC gamma
	 * settings applies.
	 * */
	void setgamma(double gamma);


	/* Get Gamma Coeff
	 * Get the image's gamma coefficient. This is experimental.
	 * */
	double getgamma(void);

	/* Bezier Curve
	 * (After Frenchman Pierre Bˇzier from Regie Renault)
	 * A collection of formulae for describing curved lines
	 * and surfaces, first used in 1972 to model automobile surfaces.
	 *             (from the The Free On-line Dictionary of Computing)
	 * See http://www.moshplant.com/direct-or/bezier/ for one of many
	 * available descriptions of bezier curves.
	 * There are four points used to define the curve: the two endpoints
	 * of the curve are called the anchor points, while the other points,
	 * which define the actual curvature, are called handles or control points.
	 * Moving the handles lets you modify the shape of the curve.
	 * */

	void bezier(int startPtX, int startPtY,
				int startControlX, int startControlY,
				int endPtX, int endPtY,
				int endControlX, int endControlY,
				double red, double green, double blue);

	void bezier(int startPtX, int startPtY,
				int startControlX, int startControlY,
				int endPtX, int endPtY,
				int endControlX, int endControlY,
				int red, int green, int blue);

	/* Set Text
	 * Sets the text information in the PNG header. If it is not called, the default is used.
	 */
	void settext(char* title, char* author, char* description, char* software);
	void settext(const char* title, const char* author, const char* description, const char* software);


	/* Version Number
	 * Returns the PNGwriter version number.
	 */
	static double version(void);

	/* Write PNG
	 * Writes the PNG image to disk. You can still change the PNGwriter instance after this.
	 * Tip: This is exactly the same as close(), but easier to remember.
	 * Tip: To make a sequence of images using only one instance of PNGwriter, alter the image, change its name,
	 * write_png(), then alter the image, change its name, write_png(), etc.
	 */
	void write_png(void);

	/* Plot Text
	 * Uses the Freetype2 library to set text in the image. face_path is the file path to a
	 * TrueType font file (.ttf) (FreeType2 can also handle other types). fontsize specifices the approximate
	 * height of the rendered font in pixels. x_start and y_start specify the placement of the
	 * lower, left corner of the text string. angle is the text angle in radians. text is the text to be rendered.
	 * The colour coordinates can be doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * Tip: PNGwriter installs a few fonts in /usr/local/share/pngwriter/fonts to get you started.
	 * Tip: Remember to add -DNO_FREETYPE to your compilation flags if PNGwriter was compiled without FreeType support.
	 * */
	void plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double red, double green, double blue);
	void plot_text(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue);


	/* Plot UTF-8 Text
	 * Same as the above, but the text to be plotted is encoded in UTF-8. Why would you want this? To be able to plot
	 * all characters available in a large TrueType font, for example: for rendering Japenese, Chinese and other
	 * languages not restricted to the standard 128 character ASCII space.
	 * Tip: The quickest way to get a string into UTF-8 is to write it in an adequate text editor, and save it as a file
	 * in UTF-8 encoding, which can then be read in in binary mode.
	 * */
	void plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, double red, double green, double blue);
	void plot_text_utf8(char* face_path, int fontsize, int x_start, int y_start, double angle, char* text, int red, int green, int blue);


	/* Bilinear Interpolation of Image
	 * Given a floating point coordinate (x from 0.0 to width, y from 0.0 to height),
	 * this function will return the interpolated colour intensity specified by
	 * colour (where red = 1, green = 2, blue = 3).
	 * bilinear_interpolate_read() returns an int from 0 to 65535, and
	 * bilinear_interpolate_dread() returns a double from 0.0 to 1.0.
	 * Tip: Especially useful for enlarging an image.
	 * */
	int bilinear_interpolation_read(double x, double y, int colour);
	double bilinear_interpolation_dread(double x, double y, int colour);

	/* Plot Blend
	 * Plots the colour given by red, green blue, but blended with the existing pixel
	 * value at that position. opacity is a double that goes from 0.0 to 1.0.
	 * 0.0 will not change the pixel at all, and 1.0 will plot the given colour.
	 * Anything in between will be a blend of both pixel levels. Please note: This is neither
	* alpha channel nor PNG transparency chunk support. This merely blends the plotted pixels.
	 * */

	void plot_blend(int x, int y, double opacity, int red, int green, int blue);
	void plot_blend(int x, int y, double opacity, double red, double green, double blue);


	/* Invert
	 * Inverts the image in RGB colourspace.
	 * */
	void invert(void);

	/* Resize Image
	 * Resizes the PNGwriter instance. Note: All image data is set to black (this is
	 * a resizing, not a scaling, of the image).
	 * */
	void resize(int width, int height);

	/* Boundary Fill
	 * All pixels adjacent to the start pixel will be filled with the fill colour, until the boundary colour is encountered.
	 * For example, calling boundary_fill() with the boundary colour set to red, on a pixel somewhere inside a red circle,
	 * will fill the entire circle with the desired fill colour. If, on the other hand, the circle is not the boundary colour,
	 * the rest of the image will be filled.
	 * The colour components are either doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * */
	void boundary_fill(int xstart, int ystart, double boundary_red,double boundary_green,double boundary_blue,double fill_red, double fill_green, double fill_blue) ;
	void boundary_fill(int xstart, int ystart, int boundary_red,int boundary_green,int boundary_blue,int fill_red, int fill_green, int fill_blue) ;

	/* Flood Fill
	 * All pixels adjacent to the start pixel will be filled with the fill colour, if they are the same colour as the
	 * start pixel. For example, calling flood_fill() somewhere in the interior of a solid blue rectangle will colour
	 * the entire rectangle the fill colour. The colour components are either doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * */
	void flood_fill(int xstart, int ystart, double fill_red, double fill_green, double fill_blue) ;
	void flood_fill(int xstart, int ystart, int fill_red, int fill_green, int fill_blue) ;

	/* Polygon
	 * This function takes an array of integer values containing the coordinates of the vertexes of a polygon.
	 * Note that if you want a closed polygon, you must repeat the first point's coordinates for the last point.
	 * It also requires the number of points contained in the array. For example, if you wish to plot a triangle,
	 * the array will contain 6 elements, and the number of points is 3. Be very careful about this; if you specify the wrong number
	 * of points, your program will either segfault or produce points at nonsensical coordinates.
	 * The colour components are either doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * */
	void polygon(int* points, int number_of_points, double red, double green, double blue);
	void polygon(int* points, int number_of_points, int red, int green, int blue);

	/* Plot CMYK
	 * Plot a point in the Cyan, Magenta, Yellow, Black colourspace. Please note that this colourspace is
	 * lossy, i.e. it cannot reproduce all colours on screen that RGB can. The difference, however, is
	 * barely noticeable. The algorithm used is a standard one. The colour components are either
	 * doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * */
	void plotCMYK(int x, int y, double cyan, double magenta, double yellow, double black);
	void plotCMYK(int x, int y, int cyan, int magenta, int yellow, int black);

	/* Read CMYK, Double version
	 * Get a pixel in the Cyan, Magenta, Yellow, Black colourspace. if 'colour' is 1, the Cyan component will be returned
	 * as a double from 0.0 to 1.0. If 'colour is 2, the Magenta colour component will be returned, and so on, up to 4.
	 * */
	double dreadCMYK(int x, int y, int colour);

	/* Read CMYK
	 * Same as the above, but the colour components returned are an int from 0 to 65535.
	 * */
	int readCMYK(int x, int y, int colour);

	/* Scale Proportional
	 * Scale the image using bilinear interpolation. If k is greater than 1.0, the image will be enlarged.
	 * If k is less than 1.0, the image will be shrunk. Negative or null values of k are not allowed.
	 * The image will be resized and the previous content will be replaced by the scaled image.
	 * Tip: use getheight() and getwidth() to find out the new width and height of the scaled image.
	 * Note: After scaling, all images will have a bit depth of 16, even if the original image had
	 * a bit depth of 8.
	 * */
	void scale_k(double k);

	/* Scale Non-Proportional
	 * Scale the image using bilinear interpolation, with different horizontal and vertical scale factors.
	 * */
	void scale_kxky(double kx, double ky);

	/* Scale To Target Width and Height
	 * Scale the image in such a way as to meet the target width and height.
	 * Tip: if you want to keep the image proportional, scale_k() might be more appropriate.
	 * */
	void scale_wh(int finalwidth, int finalheight);


	/* Blended Functions
	 * All these functions are identical to their non-blended types. They take an extra argument, opacity, which is
	 * a double from 0.0 to 1.0 and represents how much of the original pixel value is retained when plotting the
	 * new pixel. In other words, if opacity is 0.7, then after plotting, the new pixel will be 30% of the
	 * original colour the pixel was, and 70% of the new colour, whatever that may be. As usual, each function
	 * is available in int or double versions.  Please note: This is neither alpha channel nor PNG transparency chunk support. This merely blends the plotted pixels.
	 * */

	// Start Blended Functions

	void plotHSV_blend(int x, int y, double opacity, double hue, double saturation, double value);
	void plotHSV_blend(int x, int y, double opacity, int hue, int saturation, int value);

	void line_blend(int xfrom, int yfrom, int xto, int yto,  double opacity, int red, int green,int  blue);
	void line_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue);

	void square_blend(int xfrom, int yfrom, int xto, int yto, double opacity, int red, int green,int  blue);
	void square_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue);

	void filledsquare_blend(int xfrom, int yfrom, int xto, int yto, double opacity, int red, int green,int  blue);
	void filledsquare_blend(int xfrom, int yfrom, int xto, int yto, double opacity, double red, double green,double  blue);

	void circle_blend(int xcentre, int ycentre, int radius, double opacity, int red, int green, int blue);
	void circle_blend(int xcentre, int ycentre, int radius, double opacity, double red, double green, double blue);

	void filledcircle_blend(int xcentre, int ycentre, int radius, double opacity, int red, int green, int blue);
	void filledcircle_blend(int xcentre, int ycentre, int radius, double opacity, double red, double green, double blue);

	void 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);

	void 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);

	void 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);
	void 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);

	void 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);
	void 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);

	void 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) ;
	void 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) ;

	void flood_fill_blend(int xstart, int ystart, double opacity, double fill_red, double fill_green, double fill_blue) ;
	void flood_fill_blend(int xstart, int ystart, double opacity, int fill_red, int fill_green, int fill_blue) ;

	void polygon_blend(int* points, int number_of_points, double opacity, double red, double green, double blue);
	void polygon_blend(int* points, int number_of_points, double opacity,  int red, int green, int blue);

	void plotCMYK_blend(int x, int y, double opacity, double cyan, double magenta, double yellow, double black);
	void plotCMYK_blend(int x, int y, double opacity, int cyan, int magenta, int yellow, int black);

	// End of Blended Functions

	/* Laplacian
	 * This function applies a discrete laplacian to the image, multiplied by a constant factor.
	 * The kernel used in this case is:
	 *                1.0  1.0  1.0
	 *                1.0 -8.0  1.0
	 *                1.0  1.0  1.0
	 * Basically, this works as an edge detector. The current pixel is assigned the sum of all neighbouring
	 * pixels, multiplied by the corresponding kernel element. For example, imagine a pixel and its 8 neighbours:
	 *                1.0    1.0    0.0  0.0
	 *                1.0  ->1.0<-  0.0  0.0
	 *                1.0    1.0    0.0  0.0
	 * This represents a border between white and black, black is on the right. Applying the laplacian to
	 * the pixel specified above pixel gives:
	 *                1.0*1.0  + 1.0*1.0  + 0.0*1.0 +
	 *                1.0*1.0  + 1.0*-8.0 + 0.0*1.0 +
	 *                1.0*1.0  + 1.0*1.0  + 0.0*1.0   = -3.0
	 * Applying this to the pixel to the right of the pixel considered previously, we get a sum of 3.0.
	 * That is, after passing over an edge, we get a high value for the pixel adjacent to the edge. Since
	 * PNGwriter limits the colour components if they are off-scale, and the result of the laplacian
	 * may be negative, a scale factor and an offset value are included. This might be useful for
	 * keeping things within range or for bringing out more detail in the edge detection. The
	 * final pixel value will be given by:
	 *   final value =  laplacian(original pixel)*k + offset
	 * Tip: Try a value of 1.0 for k to start with, and then experiment with other values.
	 * */
	void laplacian(double k, double offset);

	/* Filled Triangle
	 * Draws the triangle specified by the three pairs of points in the colour specified
	 * by the colour coefficients. The colour components are either doubles from 0.0 to
	 * 1.0 or ints from 0 to 65535.
	 * */
	void filledtriangle(int x1,int y1,int x2,int y2,int x3,int y3, int red, int green, int blue);
	void filledtriangle(int x1,int y1,int x2,int y2,int x3,int y3, double red, double green, double blue);

	/* Filled Triangle, Blended
	 * Draws the triangle specified by the three pairs of points in the colour specified
	 * by the colour coefficients, and blended with the background. See the description for Blended Functions.
	 * The colour components are either doubles from 0.0 to 1.0 or ints from 0 to 65535.
	 * */
	void filledtriangle_blend(int x1,int y1,int x2,int y2,int x3,int y3, double opacity, int red, int green, int blue);
	void filledtriangle_blend(int x1,int y1,int x2,int y2,int x3,int y3, double opacity, double red, double green, double blue);

	/* Arrow,  Filled Arrow
	 * Plots an arrow from (x1, y1) to (x2, y2) with the arrowhead at the second point, given the size in pixels
	 * and the angle in radians of the arrowhead. The plotted arrow consists of one main line, and two smaller
	 * lines originating from the second point. Filled Arrow plots the same, but the arrowhead is a solid triangle.
	 * Tip: An angle of 10 to 30 degrees looks OK.
	 * */

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

	void filledarrow(int x1,int y1,int x2,int y2,int size, double head_angle, double red, double green, double blue);
	void filledarrow(int x1,int y1,int x2,int y2,int size, double head_angle, int red, int green, int blue);

	/* Cross, Maltese Cross
	 * Plots a simple cross at x, y, with the specified height and width, and in the specified colour.
	 * Maltese cross plots a cross, as before, but adds bars at the end of each arm of the cross.
	 * The size of these bars is specified with x_bar_height and y_bar_width.
	 * The cross will look something like this:
	 *
	 *    -----  <-- ( y_bar_width)
	 *      |
	 *      |
	 *  |-------|  <-- ( x_bar_height )
	 *      |
	 *      |
	 *    -----
	 * */

	void cross(int x, int y, int xwidth, int yheight, double red, double green, double blue);
	void cross(int x, int y, int xwidth, int yheight, int red, int green, int blue);

	void maltesecross(int x, int y, int xwidth, int yheight, int x_bar_height, int y_bar_width, double red, double green, double blue);
	void maltesecross(int x, int y, int xwidth, int yheight, int x_bar_height, int y_bar_width, int red, int green, int blue);

	/* Diamond and filled diamond
	 * Plots a diamond shape, given the x, y position, the width and height, and the colour.
	 * Filled diamond plots a filled diamond.
	 * */

	void filleddiamond(int x, int y, int width, int height, int red, int green, int blue);
	void diamond(int x, int y, int width, int height, int red, int green, int blue);

	void filleddiamond(int x, int y, int width, int height, double red, double green, double blue);
	void diamond(int x, int y, int width, int height, double red, double green, double blue);

	/* Get Text Width, Get Text Width UTF8
	 * Returns the approximate width, in pixels, of the specified *unrotated* text. It is calculated by adding
	 * each letter's width and kerning value (as specified in the TTF file). Note that this will not
	 * give the position of the farthest pixel, but it will give a pretty good idea of what area the
	 * text will occupy. Tip: The text, when plotted unrotated, will fit approximately in a box with its lower left corner at
	 * (x_start, y_start) and upper right at (x_start + width, y_start + size), where width is given by get_text_width()
	 * and size is the specified size of the text to be plotted. Tip: Text plotted at position
	 * (x_start, y_start), rotated with a given 'angle', and of a given 'size'
	 * whose width is 'width', will fit approximately inside a rectangle whose corners are at
	 *     1  (x_start, y_start)
	 *     2  (x_start + width*cos(angle), y_start + width*sin(angle))
	 *     3  (x_start + width*cos(angle) - size*sin(angle), y_start + width*sin(angle) + size*cos(angle))
	 *     4  (x_start - size*sin(angle), y_start + size*cos(angle))
	 * */

	int get_text_width(char* face_path, int fontsize,  char* text);

	int get_text_width_utf8(char* face_path, int fontsize, char* text);


};


#endif