Mercurial > sdl-ios-xcode
view docs/man3/SDL_DisplayFormatAlpha.3 @ 1030:6b8f0543337c
Date: Sat, 15 Jan 2005 15:06:01 -0600
From: Tyler Montbriand
Subject: [SDL] minor bugfix for test/testoverlay2.c
Programs that use malloc ought to #include <stdlib.h> . On 32-bit systems you
can get away with not including it, but on 64-bit systems it will assume
malloc() returns a 32-bit integer and butcher the 64-bit pointers it returns.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Tue, 18 Jan 2005 18:32:10 +0000 |
| parents | e5bc29de3f0a |
| children | 546f7c1eb755 |
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.TH "SDL_DisplayFormatAlpha" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_DisplayFormatAlpha\- Convert a surface to the display format .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBSDL_Surface *\fBSDL_DisplayFormatAlpha\fP\fR(\fBSDL_Surface *surface\fR); .SH "DESCRIPTION" .PP This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer plus an alpha channel, suitable for fast blitting onto the display surface\&. It calls \fISDL_ConvertSurface\fR .PP 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\&. .PP This function can be used to convert a colourkey to an alpha channel, if the \fBSDL_SRCCOLORKEY\fP flag is set on the surface\&. The generated surface will then be transparent (alpha=0) where the pixels match the colourkey, and opaque (alpha=255) elsewhere\&. .SH "RETURN VALUE" .PP If the conversion fails or runs out of memory, it returns \fBNULL\fR .SH "SEE ALSO" .PP \fISDL_ConvertSurface\fR, \fISDL_SetAlpha\fR, \fISDL_SetColorKey\fR, \fISDL_DisplayFormat\fR, \fISDL_Surface\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01