Merge branch 'master' into jgrpp

# Conflicts:
#	src/console_cmds.cpp
#	src/date.cpp
#	src/economy.cpp
#	src/misc.cpp
#	src/newgrf_house.cpp

src/spritecache.cpp

@@ -196,6 +196,17 @@ uint GetOriginFileSlot(SpriteID sprite)
 	return GetSpriteCache(sprite)->file_slot;
 }
 
+/**
+ * Get the GRF-local sprite id of a given sprite.
+ * @param sprite The sprite to look at.
+ * @return The GRF-local sprite id.
+ */
+uint32 GetSpriteLocalID(SpriteID sprite)
+{
+	if (!SpriteExists(sprite)) return 0;
+	return GetSpriteCache(sprite)->id;
+}
+
 /**
  * Count the sprites which originate from a specific file slot in a range of SpriteIDs.
  * @param file_slot FIOS file slot.