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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>
date Tue, 20 Aug 2002 06:08:42 +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