symbian-qemu-0.9.1-12/libsdl-trunk/docs/man3/SDL_DisplayFormatAlpha.3
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
changeset 46 b6935a90ca64
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority

.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