From 3f8ce08454230f41399403453692ddd89ea4f510 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Sat, 7 Jan 2012 01:28:06 -0500
Subject: [PATCH] Fixed bug 1224 - Blit map not updated if source palette
 changed

bastien.bouclet@gmail.com 2011-06-12 11:08:58 PDT

SDL_LowerBlit doesn't update the blit color map if the source surface has
changed.

A proposed fix is attached, storing the source palette version in the color
map.
---
 src/video/SDL_blit.h    |  3 ++-
 src/video/SDL_pixels.c  | 13 ++++++++++---
 src/video/SDL_surface.c |  4 +++-
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/video/SDL_blit.h b/src/video/SDL_blit.h
index 1e953afca..6a5983d30 100755
--- a/src/video/SDL_blit.h
+++ b/src/video/SDL_blit.h
@@ -92,7 +92,8 @@ typedef struct SDL_BlitMap
 
     /* the version count matches the destination; mismatch indicates
        an invalid mapping */
-    Uint32 palette_version;
+    Uint32 dst_palette_version;
+    Uint32 src_palette_version;
 } SDL_BlitMap;
 
 /* Functions found in SDL_blit.c */
diff --git a/src/video/SDL_pixels.c b/src/video/SDL_pixels.c
index 900ed522d..455612c50 100755
--- a/src/video/SDL_pixels.c
+++ b/src/video/SDL_pixels.c
@@ -969,7 +969,8 @@ SDL_InvalidateMap(SDL_BlitMap * map)
         return;
     }
     map->dst = NULL;
-    map->palette_version = 0;
+    map->src_palette_version = 0;
+    map->dst_palette_version = 0;
     if (map->info.table) {
         SDL_free(map->info.table);
         map->info.table = NULL;
@@ -1036,9 +1037,15 @@ SDL_MapSurface(SDL_Surface * src, SDL_Surface * dst)
     map->dst = dst;
 
     if (dstfmt->palette) {
-        map->palette_version = dstfmt->palette->version;
+        map->dst_palette_version = dstfmt->palette->version;
     } else {
-        map->palette_version = 0;
+        map->dst_palette_version = 0;
+    }
+
+    if (srcfmt->palette) {
+        map->src_palette_version = srcfmt->palette->version;
+    } else {
+        map->src_palette_version = 0;
     }
 
     /* Choose your blitters wisely */
diff --git a/src/video/SDL_surface.c b/src/video/SDL_surface.c
index 3ac55396f..05b259d81 100755
--- a/src/video/SDL_surface.c
+++ b/src/video/SDL_surface.c
@@ -494,7 +494,9 @@ SDL_LowerBlit(SDL_Surface * src, SDL_Rect * srcrect,
     /* Check to make sure the blit mapping is valid */
     if ((src->map->dst != dst) ||
         (dst->format->palette &&
-         src->map->palette_version != dst->format->palette->version)) {
+         src->map->dst_palette_version != dst->format->palette->version) ||
+        (src->format->palette &&
+         src->map->src_palette_version != src->format->palette->version)) {
         if (SDL_MapSurface(src, dst) < 0) {
             return (-1);
         }