win32加载图片获得像素值

　　在写光栅渲染器时，需要加载图片获得像素以便进行纹理插值，试了几种方法发现下面这种比价简单，效率也可以接受

　　Texture2D是我自己定义的类，其中m_pixelBuffer是一个动态二维数组，每个元素为ZCFLOAT3（自定义类型用来保存颜色rgb值）。

 #include "LoadBitmap.h"
 #include <windows.h>
 #include <gdiplus.h>

 #include <iostream>
 #include <fstream>
 #include <sstream>

 #pragma comment(lib, "gdiplus.lib")
 using namespace std;
 using namespace Gdiplus;

 Texture2D MathUtil::LoadBitmapToColorArray(wstring filePath)
 {
     GdiplusStartupInput gdiplusstartupinput;
     ULONG_PTR gdiplustoken;
     GdiplusStartup(&gdiplustoken, &gdiplusstartupinput, nullptr);

     Bitmap* bmp = new Bitmap(filePath.c_str());
     if (!bmp)
     {
         MessageBox(nullptr, "error", "picture path is null!", MB_OK);
         delete bmp;
         GdiplusShutdown(gdiplustoken);
         return Texture2D(,);
     }
     else
     {
         UINT height = bmp->GetHeight();
         UINT width = bmp->GetWidth();
         //Texture2D
         Texture2D texture(width, height);

         Color color;

         for (int y = ; y < height; y++)
             for (int x = ; x < width; x++)
             {
                 bmp->GetPixel(x, y, &color);

                 texture.m_pixelBuffer[x][y] = ZCFLOAT3(
                     color.GetRed() / .f,
                     color.GetGreen() / .f,
                     color.GetBlue() / .f
                 );
             }

         delete bmp;
         GdiplusShutdown(gdiplustoken);
         return texture;
     }

 }