SDL入门教程（七）：SDL抠色（Color Keying） 原创

I need a method to save the main-texture or a part of it to a PNG-file. IMG_SavePNG is just able to save a SDL_Surface to a file, not a SDL_Texture.

This creates a new PixelFormat object from an existing SDL_PixelFormat. It's very important not to free the original pixel format since that will cause problems ...

With this flag SDL will attempt to find the best location for this surface, either in system memory or video memory, to obtain hardware colorkey blitting ...

A SDL_PixelFormat describes the format of the pixel data stored at the pixels field of a SDL_Surface. Every surface stores a SDL_PixelFormat in the format ...

A SDL_PixelFormat describes the format of the pixel data stored at the pixels field of a SDL_Surface. Every surface stores a SDL_PixelFormat in the format field ...

A SDL_PixelFormat describes the format of the pixel data stored at the pixels field of a SDL_Surface. Every surface stores a SDL_PixelFormat in the format field ...

SDL的风格，如果SDL_SetColorkey()成功则返回0，否则返回-1。 ... 因为是类方法，所以使用起来就很直观了。我们在创建需要抠色的DisplaySurface对象之后，直接 ...

SDL_SRCCOLORKEY|SDL_RLEACCEL 表示将扣色后的图片重新编码（通常意味着重复使用时会快些）。 ... SDL的风格，如果SDL_SetColorkey()成功则返回0，否则返回-1。

SDL_SRCCOLORKEY|SDL_RLEACCEL 表示将扣色后的图片重新编码（通常意味着重复使用时会快些）。 ... SDL的风格，如果SDL_SetColorkey()成功则返回0，否则返回-1。

I've got a little problem using “colorkey” and “alpha” in the pixel format struct in a surface. Let's be sure first that I understand these ...