SDL框架無法顯示小於20x20像素的BMP文件？

Question

有沒有人知道是否有分鐘。 SDL框架中BMP文件的大小限制以顯示它們？
我在問你這個，因爲我試過了，但是無法正確顯示小於20x20像素的BMP文件（我正在使用SDL for C++）。

代碼：

bool successCondition = false; 
    if (SDL_Init(SDL_INIT_VIDEO) != 0) { 
     printf("Unable to initialize SDL: %s\n", SDL_GetError()); 
     return 1; 
    } 
    atexit(SDL_Quit); 

    SDL_Surface *screen; 

    screen = SDL_SetVideoMode(640, 480, 24, SDL_DOUBLEBUF); 
    if (screen == NULL) { 
     printf("Unable to set video mode: %s\n", SDL_GetError()); 
     return 1; 
    } 

    // nueva imagen 
    Image* imgSmile = new Image("Images/smile.bmp"); 

    SDL_Rect src, dest; 
    src.x = 0; 
    src.y = 0; 
    src.w = imgSmile->getWidth(); 
    src.h = imgSmile->getHeight(); 
    dest.x = 50; 
    dest.y = 20; 
    dest.w = imgSmile->getWidth(); 
    dest.h = imgSmile->getHeight(); 
    SDL_BlitSurface(imgSmile->getSDLSurface(), &src, screen, &dest); 
    SDL_Flip(screen); 

    // nueva imagen 
    Image* imgSmileRe = new Image("Images/smile.bmp"); 


    // Achico la imagen 
    imgSmileRe->resize(10, 10); 

    // Pego la imagen en la pantalla 
    src.x = 0; 
    src.y = 0; 
    src.w = imgSmileRe->getWidth(); 
    src.h = imgSmileRe->getHeight(); 
    dest.x = 100; 
    dest.y = 20; 
    dest.w = imgSmileRe->getWidth(); 
    dest.h = imgSmileRe->getHeight(); 
    SDL_BlitSurface(imgSmileRe->getSDLSurface(), &src, screen, &dest); 
    SDL_Flip(screen); 


    //esperar para cerrar 
    SDL_Event e; 
    bool running = true; 

    while(running) 
    { 
     while(SDL_PollEvent(&e)) 
     { 
      switch(e.type) 
      { 
       case SDL_QUIT: 
        running = false; 
        SDL_Quit(); 
        break; 
      } 
     } 
    } 

    // libero memoria 
    free(imgSmile); 
    free(imgSmileRe); 

    successCondition = true; 

    return successCondition; 

} 

並調整大小代碼：

void Image::resize(int newWidth, int newHeight) 
{ 
    int widthSrc = this->getWidth(); 
    int heightSrc = this->getHeight(); 

    // Empty new image 
    Image* temp = new Image(newWidth, newHeight); 

    int posXDst = 0; 
    int posYDst = 0; 

    for(int posYSrc = 0; posYSrc < heightSrc ; posYSrc++){ 


     for(int posXSrc = 0; posXSrc < widthSrc; posXSrc++){ 

      posXDst = (posXSrc * newWidth)/widthSrc; 
      posYDst = (posYSrc * newHeight)/heightSrc; 

      Uint32 pixelImg = this->getPixel(posXSrc, posYSrc); 


      if(posXSrc > 0 && posYSrc > 0 && newWidth > widthSrc && newHeight > heightSrc){ 

       int fromY = (((posYSrc-1) * newHeight)/heightSrc); 
       int fromX = (((posXSrc-1) * newWidth)/widthSrc); 

       // interpolacion interna 
       for (int y = fromY; y <= posYDst; y++){ 
        for (int x = fromX; x <= posXDst; x++){ 

         // pixel y posicion superior izquierdo 
         Uint32 pixelSI = this->getPixel(posXSrc-1, posYSrc-1); 
         int xSI = ((posXSrc-1) * newWidth)/widthSrc; 
         int ySI = ((posYSrc-1) * newHeight)/heightSrc; 
         // pixel y posicion superior derecho 
         Uint32 pixelSD = this->getPixel(posXSrc, posYSrc-1); 
         int xSD = (posXSrc * newWidth)/widthSrc; 
         int ySD = ((posYSrc-1) * newHeight)/heightSrc; 
         // pixel y posicion inferior izquierdo 
         Uint32 pixelII = this->getPixel(posXSrc-1, posYSrc); 
         int xII = ((posXSrc-1) * newWidth)/widthSrc; 
         int yII = (posYSrc * newHeight)/heightSrc; 

         // obtengo el pixel interpolado 
         Uint32 interpolatedPixel = this->getInterpolatedPixel(pixelSI, xSI, ySI, 
                      pixelSD, xSD, ySD, 
                      pixelII, xII, yII, 
                      pixelImg, posXDst, posYDst, 
                      x, y, temp->getFormat()); 

         // coloco el pixel en la imagen destino 
         temp->putPixel(interpolatedPixel, x, y); 
        } 
       } 
      } 

      // Pongo el pixel en las nuevas coordenadas 
      temp->putPixel(pixelImg, posXDst, posYDst); 
     } 
    } 

    this->copy(*temp); 
    free(temp); 
} 

對不起，西班牙意見。 我使用的Windows XP/7圖像是24位BMP文件aprox 20x20像素的笑臉。

Answer 1

理論上，對於BMP尺寸沒有限制（就SDL而言）。