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Date: Mon, 02 May 2005 04:23:16 -0500 From: Jonathan Atkins Subject: Re: [PATCH] *CRITICAL* 8bit direct RGB palette not being created I think that SDL_AllocFormat should create the palette for all 8bit surfaces. And when the RGBAmasks match the normal 3:3:2:0 we need to apply the old behavior. If the mask doesn't match that, then we need to make the right palette assuming the masks are valid (I don't think we validate any masks for high color surfaces...so we wouldn't here) Then there's always a palette available for the 8bit surfaces. This restores the normal behavior and allows for masks to create palettes automatically for odd masks even, which would be a neato thing to have in there, as SDL never did this before.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 16 May 2005 05:34:58 +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