view docs/man3/SDL_DisplayFormatAlpha.3 @ 610:95433459fbd2

Date: Mon, 14 Apr 2003 22:08:27 +0100 From: Patrice Mandin Subject: [SDL][PATCH] 2 patches for sdl Here are 2 patches for SDL: - One is to put the dummy video drivers at the end of the video drivers list. It gave me problems, when SDL_VIDEODRIVER is not set, and the dummy driver is used instead of the platform's driver, just because it is always available. So the dummy driver must always be at the end of the list. I suppose picogui and dc video drivers also don't work.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 15 Apr 2003 15:46:56 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.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