c++绘制png图片

#include "svpng.inc"//用于绘制png
#include "Fucker.h"//万能头文件

const int width = 256, height = 256;
unsigned char rgba[width * height * 4];

void Pixel(int x, int y, int r, int g, int b, int a)
{
    int idx = (y * width + x)*4;
    rgba[idx++] = r;
    rgba[idx++] = b;
    rgba[idx++] = b;
    rgba[idx++] = a;
}

int main(void) {
    FILE* fp;
    fopen_s(&fp, "rgba.png", "wb");




    for (int y = 0; y < 256; y++)
        for (int x = 0; x < 256; x++) {      
            Pixel(x, y, 255, 0, 0, 255);
        }




    svpng(fp, 256, 256, rgba, 1);
    fclose(fp);
    return 0;
}

png头文件

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