libj/J/texture.h

//
//  texture.h
//  J
//
//  Created by Joshua Moerman on 6/23/12.
//  Copyright (c) 2012 Vadovas. All rights reserved.
//

#ifndef J_texture_h
#define J_texture_h

#include "basic.h"
#include <vector>
#include <algorithm>

namespace J {

struct no_texture {};
	
template <typename T>
struct gl_type {};

template <>
struct gl_type<uint8_t> {
	static constexpr GLenum value = GL_UNSIGNED_BYTE;
};

template <typename T = uint8_t>
struct rgba {
	typedef typename std::vector<T>::iterator iterator;
	typedef typename std::vector<T>::iterator const_iterator;
	typedef typename std::vector<T>::size_type size_type;
	static constexpr GLenum gl_type = J::gl_type<T>::value;
	static constexpr GLenum gl_format = GL_RGBA;
	
	rgba(size_type w, size_type h, T const * data = nullptr)
	: width_(w)
	, height_(h)
	, pixels(w*h*4){
		if(data)
			std::copy_n(data, w*h*4, pixels.begin());
	}
	
	size_type size() const { return pixels.size(); }
	size_type width() const { return width; }
	size_type height() const { return height; }
	
	struct row_proxy {
		row_proxy(T* data) : data(data) {}
		T& operator[](size_type x){ return data[x]; }
		T operator[](size_type x) const { return data[x]; }
		T* data;
	};
	
	row_proxy operator[](size_type y){
		return &pixels[y*width()];
	}
	
	struct const_row_proxy {
		const_row_proxy(T const * data) : data(data) {}
		T operator[](size_type x) const { return data[x]; }
		T const * data;
	};
	
	const_row_proxy operator[](size_type y) const {
		return &pixels[y*width()];
	}
	
	T * data() { return pixels.data(); }
	T const * data() const { return pixels.data(); }
	
	iterator begin() { return pixels.begin(); }
	iterator end() { return pixels.begin(); }
	
	const_iterator begin() const { return pixels.begin(); }
	const_iterator end() const { return pixels.begin(); }
	
private:
	size_type width_;
	size_type height_;
	std::vector<T> pixels;
};
	
}

#endif