From cdde70c9b698ed052d4a533742ea9894191694dd Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Fri, 3 Apr 2009 13:27:33 +0000
Subject: [PATCH] Added SDL_GetColorKey()

---
 include/SDL_surface.h   | 13 +++++++++++++
 src/video/SDL_surface.c | 17 +++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/include/SDL_surface.h b/include/SDL_surface.h
index 3a4abba93..304482911 100644
--- a/include/SDL_surface.h
+++ b/include/SDL_surface.h
@@ -199,6 +199,19 @@ extern DECLSPEC int SDLCALL SDL_SetSurfaceRLE(SDL_Surface * surface,
 extern DECLSPEC int SDLCALL SDL_SetColorKey(SDL_Surface * surface,
                                             Uint32 flag, Uint32 key);
 
+/*
+ * \fn int SDL_GetColorKey(SDL_Surface *surface, Uint32 *key)
+ *
+ * \brief Sets the color key (transparent pixel) in a blittable surface.
+ *
+ * \param surface The surface to update
+ * \param key A pointer filled in with the transparent pixel in the native surface format
+ *
+ * \return 0 on success, or -1 if the surface is not valid or colorkey is not enabled.
+ */
+extern DECLSPEC int SDLCALL SDL_GetColorKey(SDL_Surface * surface,
+                                            Uint32 * key);
+
 /**
  * \fn int SDL_SetSurfaceColorMod(SDL_Surface *surface, Uint8 r, Uint8 g, Uint8 b)
  *
diff --git a/src/video/SDL_surface.c b/src/video/SDL_surface.c
index ee642dc97..02b2c6993 100644
--- a/src/video/SDL_surface.c
+++ b/src/video/SDL_surface.c
@@ -272,6 +272,23 @@ SDL_SetColorKey(SDL_Surface * surface, Uint32 flag, Uint32 key)
     return 0;
 }
 
+int
+SDL_GetColorKey(SDL_Surface * surface, Uint32 * key)
+{
+    if (!surface) {
+        return -1;
+    }
+
+    if (!(surface->map->info.flags & SDL_COPY_COLORKEY)) {
+        return -1;
+    }
+
+    if (key) {
+        *key = surface->map->info.colorkey;
+    }
+    return 0;
+}
+
 /* This is a fairly slow function to switch from colorkey to alpha */
 static void
 SDL_ConvertColorkeyToAlpha(SDL_Surface * surface)