From d8a33d73cc387acaab8cf6ee3db540aba5c9eb82 Mon Sep 17 00:00:00 2001
From: Eric Wasylishen <ewasylishen@gmail.com>
Date: Mon, 8 Sep 2014 04:31:26 +0000
Subject: [PATCH] R_CullSurfaces: small optimization. Avoid doing (s->visframe
 == r_visframecount) test on all world surfaces, instead, use the surfaces in
 the world texture chains, which already passed that test in R_MarkSurfaces.

git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk/quakespasm@991 af15c1b1-3010-417e-b628-4374ebc0bcbd
---
 Quake/r_world.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/Quake/r_world.c b/Quake/r_world.c
index f1ab0444..c0830beb 100644
--- a/Quake/r_world.c
+++ b/Quake/r_world.c
@@ -203,14 +203,21 @@ void R_CullSurfaces (void)
 {
 	msurface_t *s;
 	int i;
+	texture_t *t;
 
 	if (!r_drawworld_cheatsafe)
 		return;
 
-	s = &cl.worldmodel->surfaces[cl.worldmodel->firstmodelsurface];
-	for (i=0 ; i<cl.worldmodel->nummodelsurfaces ; i++, s++)
+// ericw -- instead of testing (s->visframe == r_visframecount) on all world
+// surfaces, use the chained surfaces, which is exactly the same set of sufaces
+	for (i=0 ; i<cl.worldmodel->numtextures ; i++)
 	{
-		if (s->visframe == r_visframecount)
+		t = cl.worldmodel->textures[i];
+
+		if (!t || !t->texturechains[chain_world])
+			continue;
+
+		for (s = t->texturechains[chain_world]; s; s = s->texturechain)
 		{
 			if (R_CullBox(s->mins, s->maxs) || R_BackFaceCull (s))
 				s->culled = true;