# HG changeset patch
# User Sam Lantinga <slouken@libsdl.org>
# Date 1239583992 0
# Node ID 69bcba65c38834a3fdd7aad91ab48dd59afc10e3
# Parent  a6f635e5eaa6509da9c03efc90467c6286a43cc6
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.

diff -r a6f635e5eaa6 -r 69bcba65c388 src/video/windx5/SDL_dx5video.c
--- a/src/video/windx5/SDL_dx5video.c	Thu Apr 02 04:43:36 2009 +0000
+++ b/src/video/windx5/SDL_dx5video.c	Mon Apr 13 00:53:12 2009 +0000
@@ -2266,6 +2266,8 @@
 				SDL_colors[j].peGreen = colors[i].g;
 				SDL_colors[j].peBlue = colors[i].b;
 			}
+			/* This sends an WM_PALETTECHANGED message to us */
+			colorchange_expected = 1;
 			IDirectDrawPalette_SetEntries(SDL_palette, 0,
 				firstcolor, ncolors, &SDL_colors[firstcolor]);
 			alloct_all = 1;