[AD] modex+dither bugfix

[Sven Sandberg <svens@xxxxxxxxxx>]

Hi,
When blitting to a mode-X screen, it doesn't dither even if the dither 
flag is set. This patch fixes it. Tested under djgpp.
--
Sven

Index: src/blit.c
===================================================================
RCS file: /cvsroot/alleg/allegro/src/blit.c,v
retrieving revision 1.11
diff -u -r1.11 blit.c
--- src/blit.c	12 Sep 2002 16:23:56 -0000	1.11
+++ src/blit.c	10 Oct 2003 20:26:13 -0000
@@ -622,14 +622,18 @@
    int prev_drawmode = _drawing_mode;
    _drawing_mode = DRAW_MODE_SOLID;
 
-   for (y=0; y<h; y++) {
-      for (x=0; x<w; x++) {
-         c = getpixel(src, s_x+x, s_y+y);
-         r = getr_depth(src_depth, c);
-         g = getg_depth(src_depth, c);
-         b = getb_depth(src_depth, c);
-         c = makecol_depth(dest_depth, r, g, b);
-         putpixel(dest, d_x+x, d_y+y, c);
+   if ((src_depth != 8) && (_color_conv & COLORCONV_DITHER_PAL))
+      dither_blit(src, dest, s_x, s_y, d_x, d_y, w, h);
+   else {
+      for (y=0; y<h; y++) {
+         for (x=0; x<w; x++) {
+            c = getpixel(src, s_x+x, s_y+y);
+            r = getr_depth(src_depth, c);
+            g = getg_depth(src_depth, c);
+            b = getb_depth(src_depth, c);
+            c = makecol_depth(dest_depth, r, g, b);
+            putpixel(dest, d_x+x, d_y+y, c);
+         }
       }
    }