Mercurial > sdl-ios-xcode

view docs/man3/SDL_MapRGBA.3 @ 911:04a403e4ccf5

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Date: Mon, 3 May 2004 03:15:01 +0100 From: David Symmonds Subject: SDL Typedef Structs Hi, Thanks for the SDL libraries, I have been using them for about a year now and they are really brilliant. One thing that I have just found whilst using them through C++ (and needing forward declarations) is that when you typedef structs you sometimes use typedef struct Name { ... }Name; e.g. SDL_Surface and other times use typedef struct { ... }Name; e.g. SDL_Rect The first type works fine, when I define a header file I can just put 'struct Name;' at the top and use the Name throughout. However, the second type is harder to use in a header, and I haven't found a way yet, other than to include 'SDL.h' in the header file (undesirable). Would there be any harm in changing the definition of SDL_Rect and such like to the second form?
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Jul 2004 22:57:40 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_MapRGBA" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_MapRGBA\- Map a RGBA color value to a pixel format\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBUint32 \fBSDL_MapRGBA\fP\fR(\fBSDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b, Uint8 a\fR);
.SH "DESCRIPTION"
.PP
Maps the RGBA color value to the specified pixel format and returns the pixel value as a 32-bit int\&.
.PP
If the format has a palette (8-bit) the index of the closest matching color in the palette will be returned\&.
.PP
If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette)\&.
.SH "RETURN VALUE"
.PP
A pixel value best approximating the given RGBA color value for a given pixel format\&. If the pixel format bpp (color depth) is less than 32-bpp then the unused upper bits of the return value can safely be ignored (e\&.g\&., with a 16-bpp format the return value can be assigned to a \fBUint16\fP, and similarly a \fBUint8\fP for an 8-bpp format)\&.
.SH "SEE ALSO"
.PP
\fISDL_GetRGB\fR, \fISDL_GetRGBA\fR, \fISDL_MapRGB\fR, \fISDL_PixelFormat\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01