Golang C.SDL_DisplayFormatAlpha类(方法)实例源码

// Converts a surface to the display format with alpha
func (s *Surface) DisplayFormatAlpha() *Surface {
	s.mutex.RLock()
	p := C.SDL_DisplayFormatAlpha(s.cSurface)
	s.mutex.RUnlock()
	return wrap(p)
}

// Converts a surface to the display format with alpha
func DisplayFormatAlpha(src *Surface) *Surface {
	p := C.SDL_DisplayFormatAlpha((*C.SDL_Surface)(cast(src)))
	return (*Surface)(cast(p))
}

type imageKey struct {
	path   string
	width  int
	height int
}

func (me *imageKey) String() string {
	return me.path + strconv.Itoa(me.width) + strconv.Itoa(me.height)
}

//Resizes images from imageFiles and caches them.
var images = newFlyweight(
	func(path key) interface{} {
		key := path.(*imageKey)
		tmp := C.IMG_Load(C.CString(key.path))
		i := C.SDL_DisplayFormatAlpha(tmp)
		C.SDL_FreeSurface(tmp)
		if key.width != -1 && key.height != -1 {
			if (i != nil) && (int(i.w) != key.width || int(i.h) != key.height) {
				i = resize(i, key.width, key.height)
			}
		}
		return i
	},
	func(path key, img interface{}) {
		i := img.(*C.SDL_Surface)
		C.SDL_FreeSurface(i)
	})

type Image struct {
	img *C.SDL_Surface

func (s *Surface) DisplayFormatAlpha() *Surface {
	return (*Surface)(C.SDL_DisplayFormatAlpha(s.Get()))
}

// This function takes a surface and copies it to a new surface of the
// pixel format and colors of the video framebuffer (if possible),
// suitable for fast alpha blitting onto the display surface.
// The new surface will always have an alpha channel.
//
// If you want to take advantage of hardware colorkey or alpha blit
// acceleration, you should set the colorkey and alpha value before
// calling this function.
//
// If the conversion fails or runs out of memory, it returns NULL
func displayFormatAlpha(surface *C.SDL_Surface) *C.SDL_Surface {
	return C.SDL_DisplayFormatAlpha(surface)
}