尝试在c++中编写ppm图像

#include <iostream>
#include <fstream>
#include <vector>

void createPPMImage(const std::string& filename, int width, int height, const std::vector<int>& pixels) {
    std::ofstream file(filename, std::ios::binary);
    
    // 写入PPM文件头
    file << "P6\n";
    file << width << " " << height << "\n";
    file << "255\n";
    
    // 写入像素数据
    for (int i = 0; i < width * height; ++i) {
        int r = (pixels[i] >> 16) & 0xFF;
        int g = (pixels[i] >> 8) & 0xFF;
        int b = pixels[i] & 0xFF;
        
        file << static_cast<char>(r) << static_cast<char>(g) << static_cast<char>(b);
    }
    
    file.close();
}

int main() {
    int width = 800;
    int height = 600;
    std::vector<int> pixels(width * height);
    
    // 填充像素数据（示例）
    for (int i = 0; i < width * height; ++i) {
        int r = i % 256;
        int g = (i / 256) % 256;
        int b = (i / (256 * 256)) % 256;
        
        pixels[i] = (r << 16) | (g << 8) | b;
    }
    
    createPPMImage("image.ppm", width, height, pixels);
    
    return 0;
}