SDL2.0的加载图片贴图

加载图片贴图，采用了SDL_Window、SDL_Renderer、SDL_Texture和SDL_Image库

实例：

 #include <stdio.h>
 #include <math.h>
 #include <string.h>
 #include <SDL2\SDL.h>
 #include <SDL2\SDL_image.h>
 #include <SDL2\ex\SDL_rectex.h>

 SDL_Window *sdlWindow = NULL;
 SDL_Renderer *sdlRender = NULL;
 SDL_Texture *sdlTexture = NULL;
 SDL_Rect srcRect;
 SDL_Rect dstRect;
 int w = ;
 int h = ;

 bool InitView(int width, int height, const char *iconName)
 {
     //初始化窗体
     SDL_Init(SDL_INIT_VIDEO);

     sdlWindow = SDL_CreateWindow(
         "The First SDL Program",
         SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, width, height,
         SDL_WINDOW_RESIZABLE);
     if (sdlWindow == NULL) return false;

     //加载窗体图标
     SDL_Surface *iconSurface = IMG_Load(iconName);
     if (iconSurface == NULL) return false;

     SDL_SetWindowIcon(sdlWindow, iconSurface);

     return true;
 }

 bool InitDraw(const char *imgName)
 {
     //加载渲染器
     sdlRender = SDL_CreateRenderer(sdlWindow, -, );
     if (sdlRender == NULL) return false;
     SDL_SetRenderDrawColor(sdlRender, , , , );

     //加载绘画图片
     SDL_Surface *sdlSurface = IMG_Load(imgName);
     if (sdlSurface == NULL) return false;

     //加载绘画纹理
     sdlTexture = SDL_CreateTextureFromSurface(sdlRender, sdlSurface);
     if (sdlTexture == NULL) return false;

     SDL_FreeSurface(sdlSurface);
     return true;
 }

 void UpdateDraw()
 {
     SDL_RenderClear(sdlRender);

     //分X宫格
     const int count = ;
     const int sqrtCount = (int)sqrt((double)count);
     for (int i = ; i < sqrtCount; i++)    {
         srcRect = SDL_RectMake(, , (w-sqrtCount)/sqrtCount, (h-sqrtCount)/sqrtCount);
         for (int j = ; j < sqrtCount; j++) {
             srcRect.x = srcRect.w*j+(j?*j:);
             srcRect.y = srcRect.h*i+(i?*i:);

             //SDL_RectPrint("srcRect", srcRect);
             SDL_RectCopy(&srcRect, &dstRect);
             //SDL_RectPrint("dstRect", dstRect);
             SDL_RenderCopy(sdlRender, sdlTexture, &srcRect, &dstRect);
         }
     }

     SDL_RenderPresent(sdlRender);
 }

 void Quit(int code)
 {
     const char *errMsg = SDL_GetError();
     if (errMsg && strlen(errMsg)) {
         SDL_Log("Error : %s\n", errMsg);
     }

     //销毁窗口、渲染器、纹理
     if (sdlWindow) SDL_DestroyWindow(sdlWindow);
     if (sdlRender) SDL_DestroyRenderer(sdlRender);
     if (sdlTexture) SDL_DestroyTexture(sdlTexture);
     SDL_Quit();
     exit(code);
 }

 void HandleKeyEvent(const SDL_Keysym* keysym)
 {
     int key = keysym->sym;
     switch(key)
     {
     case SDLK_ESCAPE:
         Quit();
         break;
     case SDLK_SPACE:
         break;
     case SDLK_UP:
     case SDLK_DOWN:
     case SDLK_LEFT:
     case SDLK_RIGHT:
         int x, y;
         SDL_GetWindowPosition(sdlWindow, &x, &y);
         x = (key == SDLK_LEFT ? x- : (key == SDLK_RIGHT ? x+ : x));
         y = (key == SDLK_UP ? y- : (key == SDLK_DOWN ? y+ : y));
         SDL_SetWindowPosition(sdlWindow, x, y);
         SDL_Log("x=%d, y=%d\n", x, y);
         break;
     case SDLK_KP_PLUS:
     case SDLK_KP_MINUS:
         w = (key == SDLK_KP_PLUS ? w+ : w-);
         h = (key == SDLK_KP_PLUS ? h+ : h-);
         SDL_SetWindowSize(sdlWindow, w, h);
         SDL_Log("w=%d, h=%d\n", w, h);
         break;
     default:
         break;
     }
 }

 void HandleEvents()
 {
     //Our SDL event placeholder.
     SDL_Event event;
     //Grab all the events off the queue.
     while(SDL_PollEvent(&event)) {
         switch(event.type) {
         case SDL_KEYDOWN:
             //Handle key Event
             HandleKeyEvent(&event.key.keysym);
             break;
         case SDL_QUIT:
             //Handle quit requests (like Ctrl-c).
             Quit();
             break;
         }
     }
 }

 int main(int argc, char* argv[])
 {
     printf("可以通过↑↓←→+ -按键控制移动和大小\n");
     if (InitView(w, h, "yp.ico") == false) {
         SDL_Log("sdlWindow is null @_@\n");
         Quit();
         return -;
     }

     char *imgName = "gril.jpg";
     if (InitDraw(imgName) == false) {
         SDL_Log("Init Fail @_@\n");
         Quit();
         return -;
     }

     //配置客户区大小
     SDL_QueryTexture(sdlTexture,NULL, NULL, &w, &h);
     SDL_SetWindowSize(sdlWindow, w, h);
     SDL_Log("w=%d, h=%d\n", w, h);

     while () {
         HandleEvents();
         UpdateDraw();
     }

     SDL_DestroyWindow(sdlWindow);
     SDL_Quit();
     return ;
 }

结果：