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view docs/man3/SDL_MapRGB.3 @ 1258:b2283b0ded26
Date: Thu, 19 Jan 2006 20:02:29 +0200
From: Vassilis Virvilis <vasvir@iit.demokritos.gr>
Subject: [SDL] Request: Please reconsider adding tag in SDL_Event
Hi,
Patch in question:
--- include/SDL_events.h 20 Aug 2004 18:57:01 -0000 1.11
+++ include/SDL_events.h 19 Jan 2006 17:35:09 -0000
@@ -214,7 +214,7 @@
} SDL_SysWMEvent;
/* General event structure */
-typedef union {
+typedef union SDL_Event {
Uint8 type;
SDL_ActiveEvent active;
SDL_KeyboardEvent key;
Reasoning:
----------
1) Allows forward declaration of the SDL_Event union in C++. Please
note that in plain C it is possible to forward declare it.
2) Forward declaration is good because it allows encapsulation. It hides
the specific implementation and does not necessarily exposes SDL staff
to my appication's namespace
3) It can't harm plain C because tags are living in a different namespace
than typenames
4) It is already done like this in other places in SDL. Check for example
SDL_KeySym, and SDL_.*Event structures.
5) Right now I have to include SDL/event.h from a C++ header file. See 2)
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 20 Jan 2006 13:07:25 +0000 (2006-01-20) |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
line wrap: on
line source
.TH "SDL_MapRGB" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_MapRGB\- Map a RGB color value to a pixel format\&. .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBUint32 \fBSDL_MapRGB\fP\fR(\fBSDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b\fR); .SH "DESCRIPTION" .PP Maps the RGB 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 an alpha component it will be returned as all 1 bits (fully opaque)\&. .SH "RETURN VALUE" .PP A pixel value best approximating the given RGB 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 \fI\fBSDL_GetRGB\fP\fR, \fI\fBSDL_GetRGBA\fP\fR, \fI\fBSDL_MapRGBA\fP\fR, \fI\fBSDL_PixelFormat\fR\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01