-extern int GfxElementLast[MM_MAX_PLAYFIELD_WIDTH][MM_MAX_PLAYFIELD_HEIGHT];
-extern int GfxGraphicLast[MM_MAX_PLAYFIELD_WIDTH][MM_MAX_PLAYFIELD_HEIGHT];
-extern int GfxGraphic[MM_MAX_PLAYFIELD_WIDTH][MM_MAX_PLAYFIELD_HEIGHT];
-extern int GfxFrame[MM_MAX_PLAYFIELD_WIDTH][MM_MAX_PLAYFIELD_HEIGHT];
+// ----------------------------------------------------------------------------
+// exported functions
+// ----------------------------------------------------------------------------