Mercurial > sdl-ios-xcode

view docs/man3/SDL_DisplayFormatAlpha.3 @ 4286:9ea4413f0a9e SDL-1.2

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fixed bug #831 Andrey 2009-10-09 08:08:04 PDT gapi_hires_fix I made a mistake with the conclusions. And last time I as was mistaken with conclusions. Now I thought about in more detail the algorithm works. I have made it that the project fheroes2 well worked. The result of my work in attachment. I have a possibility to check up it on different models pocketpc. I checked various modes screen of 320x320, 320x240, 640x480, 800x400.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 10 Oct 2009 02:03:53 +0000
parents 4e3b250c950e
children 1238da4a7112
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