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//
// Created by saintruler on 04.05.19.
//

#ifndef OPENGLTEST_CANVAS_H
#define OPENGLTEST_CANVAS_H

#include <glad/glad.h>
#include <GLFW/glfw3.h>

#include <iostream>

struct Color
{
    unsigned int r = 0, g = 0, b = 0;
};

class Canvas
{
public:
    Canvas(int width, int height)
    {
        this->width = width;
        this->height = height;

        canvas = (unsigned char*) malloc(width * height * 3);
        glGenTextures(1, &texture);
    }

    void SetPixel(int x, int y, Color color)
    {
        glBindTexture(GL_TEXTURE_2D, texture); // all upcoming GL_TEXTURE_2D operations now have effect on this texture object

        // set texture wrapping to GL_REPEAT (default wrapping method)
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

        // set texture filtering parameters
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

        canvas[y * width * 3 + x * 3 + 0] = color.r;
        canvas[y * width * 3 + x * 3 + 1] = color.g;
        canvas[y * width * 3 + x * 3 + 2] = color.b;


        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, width, 0, GL_RGB, GL_UNSIGNED_BYTE, canvas);
        glGenerateMipmap(GL_TEXTURE_2D);
    }

    unsigned int* GetTexture()
    {
        return &(this->texture);
    }

private:
    int width, height;
    unsigned char* canvas;
    unsigned int texture;
};

#endif //OPENGLTEST_CANVAS_H