Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_MapRGBA.3 @ 461:1d36f593078a
Date: Thu, 18 Jul 2002 23:51:40 +0200 (MEST)
From: Krister Walfridsson
Subject: [SDL] src/joystick/bsd/SDL_sysjoystick.c patch
The *BSD USB HID joystick code has two serious bugs:
1. If a joystick reports unhandled hid_input usage (for example HUG_RZ or
HUG_DIAL), then the last handled value will be overwritten with an
arbitrary value. (Fixed in the patch below by adding a default case.)
2. The current code does only handle logical coordinates in the range 0-255,
while a big part of available joysticks report -128 - 127. (This is solved
in the patch below by first center the range around 0, and then stretch
it to the correct range.)
author | Sam Lantinga <slouken@libsdl.org> |
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date | Tue, 20 Aug 2002 06:08:42 +0000 |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
rev | line source |
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181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
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1 .TH "SDL_MapRGBA" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" |
0 | 2 .SH "NAME" |
3 SDL_MapRGBA\- Map a RGBA color value to a pixel format\&. | |
4 .SH "SYNOPSIS" | |
5 .PP | |
6 \fB#include "SDL\&.h" | |
7 .sp | |
8 \fBUint32 \fBSDL_MapRGBA\fP\fR(\fBSDL_PixelFormat *fmt, Uint8 r, Uint8 g, Uint8 b, Uint8 a\fR); | |
9 .SH "DESCRIPTION" | |
10 .PP | |
11 Maps the RGBA color value to the specified pixel format and returns the pixel value as a 32-bit int\&. | |
12 .PP | |
13 If the format has a palette (8-bit) the index of the closest matching color in the palette will be returned\&. | |
14 .PP | |
15 If the specified pixel format has no alpha component the alpha value will be ignored (as it will be in formats with a palette)\&. | |
16 .SH "RETURN VALUE" | |
17 .PP | |
18 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)\&. | |
19 .SH "SEE ALSO" | |
20 .PP | |
21 \fISDL_GetRGB\fR, \fISDL_GetRGBA\fR, \fISDL_MapRGB\fR, \fISDL_PixelFormat\fR | |
181
e5bc29de3f0a
Updated from the SDL Documentation Project
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
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22 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |