diff --git a/tools/quake3/q3map2/q3map2.h b/tools/quake3/q3map2/q3map2.h
index fb723ead..fe25f582 100644
--- a/tools/quake3/q3map2/q3map2.h
+++ b/tools/quake3/q3map2/q3map2.h
@@ -316,7 +316,8 @@ abstracted bsp file
 #define	MAX_MAP_PORTALS			0x20000
 #define	MAX_MAP_LIGHTING		0x800000
 #define	MAX_MAP_LIGHTGRID		0x100000	//%	0x800000 /* ydnar: set to points, not bytes */
-#define	MAX_MAP_VISIBILITY		0x200000
+#define MAX_MAP_VISCLUSTERS     0x4000 // <= MAX_MAP_LEAFS
+#define	MAX_MAP_VISIBILITY		(VIS_HEADER_SIZE + MAX_MAP_VISCLUSTERS * (((MAX_MAP_VISCLUSTERS + 63) & ~63) >> 3))
 
 #define	MAX_MAP_DRAW_SURFS		0x20000
 #define	MAX_MAP_DRAW_INDEXES	0x80000