Mercurial > sdl-ios-xcode
annotate docs/man3/SDL_MapRGBA.3 @ 4168:69bcba65c388 SDL-1.2
Fixed bug #526
Comment #1 From Simon Howard 2009-03-20 16:50:56
Hi,
I'm the author of Chocolate Doom, one of the other source ports that James
mentioned. This is a patch against the current SVN version of SDL 1.2 that
fixes the bug. It has been tested and hopefully should be obviously correct
from examining the changes. I'll give a brief explanation.
When the palette is set with SDL_SetPalette, the IDirectDrawPalette_SetEntries
DirectX function is invoked. However, when this happens, a WM_PALETTECHANGED
message is sent to the window.
A WM_PALETTECHANGED message can also be received if the palette is changed for
some other reason, like if the system palette is changed. Therefore, the
palette change handler (DX5_PaletteChanged) has code to deal with this case.
It distinguishes "expected" palette changes (set with SDL_SetPalette) from
"unexpected" palette changes using the colorchange_expected variable, which is
set before calling IDirectDrawPalette_SetEntries. However, the code to set
this variable is missing in the fullscreen code path. By setting this
variable, the palette change is handled properly and the freezes go away.
author | Sam Lantinga <slouken@libsdl.org> |
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date | Mon, 13 Apr 2009 00:53:12 +0000 |
parents | 4e3b250c950e |
children | 1238da4a7112 |
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" |
4107
4e3b250c950e
Erik Heckers fixed bug #493
Sam Lantinga <slouken@libsdl.org>
parents:
181
diff
changeset
|
3 SDL_MapRGBA \- Map a RGBA color value to a pixel format\&. |
0 | 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
|
22 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01 |