Mercurial > sdl-ios-xcode
view docs/man3/SDL_GetRGBA.3 @ 2222:926294b2bb4e
Emphasized the separation between SDL_Surface and SDL_Texture
- SDL_Surface is a system memory representation of pixel data
- SDL_Texture is a video memory representation of pixel data
The concept of SDL_Surface with SDL_HWSURFACE is no longer used.
Separated SDL_Texture types by usage rather than memory type
- SDL_TEXTUREACCESS_STATIC is for rarely changed pixel data,
can be placed in video memory.
- SDL_TEXTUREACCESS_STREAMING is for frequently changing pixel
data, usually placed in system memory or AGP memory.
Optimized the SDL_compat usage of the OpenGL renderer by only
using one copy of the framebuffer instead of two.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sat, 11 Aug 2007 20:54:31 +0000 |
| parents | e5bc29de3f0a |
| children | 546f7c1eb755 |
line wrap: on
line source
.TH "SDL_GetRGBA" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_GetRGBA\- Get RGBA values from a pixel in the specified pixel format\&. .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBvoid \fBSDL_GetRGBA\fP\fR(\fBUint32 pixel, SDL_PixelFormat *fmt, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a\fR); .SH "DESCRIPTION" .PP Get RGBA component values from a pixel stored in the specified pixel format\&. .PP This function uses the entire 8-bit [0\&.\&.255] range when converting color components from pixel formats with less than 8-bits per RGB component (e\&.g\&., a completely white pixel in 16-bit RGB565 format would return [0xff, 0xff, 0xff] not [0xf8, 0xfc, 0xf8])\&. .PP If the surface has no alpha component, the alpha will be returned as 0xff (100% opaque)\&. .SH "SEE ALSO" .PP \fISDL_GetRGB\fR, \fISDL_MapRGB\fR, \fISDL_MapRGBA\fR, \fISDL_PixelFormat\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01