From b099255748edaec547242e7f165c4016a8bad69b Mon Sep 17 00:00:00 2001
From: SmileTheory <SmileTheory@gmail.com>
Date: Wed, 19 Mar 2014 17:59:07 -0700
Subject: [PATCH] #6095: OpenGL2: Use areamask and leaf cluster for PVS when
 VIS is missing.

---
 code/renderergl2/tr_bsp.c   |  2 --
 code/renderergl2/tr_local.h |  2 --
 code/renderergl2/tr_world.c | 45 +++++++++++--------------------------
 3 files changed, 13 insertions(+), 36 deletions(-)

diff --git a/code/renderergl2/tr_bsp.c b/code/renderergl2/tr_bsp.c
index 2198646e..63824284 100644
--- a/code/renderergl2/tr_bsp.c
+++ b/code/renderergl2/tr_bsp.c
@@ -600,8 +600,6 @@ static	void R_LoadVisibility( lump_t *l ) {
 	byte	*buf;
 
 	len = ( s_worldData.numClusters + 63 ) & ~63;
-	s_worldData.novis = ri.Hunk_Alloc( len, h_low );
-	Com_Memset( s_worldData.novis, 0xff, len );
 
     len = l->filelen;
 	if ( !len ) {
diff --git a/code/renderergl2/tr_local.h b/code/renderergl2/tr_local.h
index 2e4b3e5e..d5ebe544 100644
--- a/code/renderergl2/tr_local.h
+++ b/code/renderergl2/tr_local.h
@@ -1181,8 +1181,6 @@ typedef struct {
 	int			clusterBytes;
 	const byte	*vis;			// may be passed in by CM_LoadMap to save space
 
-	byte		*novis;			// clusterBytes of 0xff
-
 	char		*entityString;
 	char		*entityParsePoint;
 } world_t;
diff --git a/code/renderergl2/tr_world.c b/code/renderergl2/tr_world.c
index dba15c45..f4edbb03 100644
--- a/code/renderergl2/tr_world.c
+++ b/code/renderergl2/tr_world.c
@@ -644,7 +644,7 @@ R_ClusterPVS
 */
 static const byte *R_ClusterPVS (int cluster) {
 	if (!tr.world->vis || cluster < 0 || cluster >= tr.world->numClusters ) {
-		return tr.world->novis;
+		return NULL;
 	}
 
 	return tr.world->vis + cluster * tr.world->clusterBytes;
@@ -698,29 +698,21 @@ static void R_MarkLeaves (void) {
 
 	for(i = 0; i < MAX_VISCOUNTS; i++)
 	{
-		if(tr.visClusters[i] == cluster)
+		// if the areamask or r_showcluster was modified, invalidate all visclusters
+		// this caused doors to open into undrawn areas
+		if (tr.refdef.areamaskModified || r_showcluster->modified)
 		{
-			//tr.visIndex = i;
-			break;
+			tr.visClusters[i] = -2;
 		}
-	}
-
-	// if r_showcluster was just turned on, remark everything 
-	if(i != MAX_VISCOUNTS && !tr.refdef.areamaskModified && !r_showcluster->modified)// && !r_dynamicBspOcclusionCulling->modified)
-	{
-		if(tr.visClusters[i] != tr.visClusters[tr.visIndex] && r_showcluster->integer)
+		else if(tr.visClusters[i] == cluster)
 		{
-			ri.Printf(PRINT_ALL, "found cluster:%i  area:%i  index:%i\n", cluster, leaf->area, i);
+			if(tr.visClusters[i] != tr.visClusters[tr.visIndex] && r_showcluster->integer)
+			{
+				ri.Printf(PRINT_ALL, "found cluster:%i  area:%i  index:%i\n", cluster, leaf->area, i);
+			}
+			tr.visIndex = i;
+			return;
 		}
-		tr.visIndex = i;
-		return;
-	}
-
-	// if the areamask was modified, invalidate all visclusters
-	// this caused doors to open into undrawn areas
-	if (tr.refdef.areamaskModified)
-	{
-		memset(tr.visClusters, -2, sizeof(tr.visClusters));
 	}
 
 	tr.visIndex = (tr.visIndex + 1) % MAX_VISCOUNTS;
@@ -734,17 +726,6 @@ static void R_MarkLeaves (void) {
 		}
 	}
 
-	// set all nodes to visible if there is no vis
-	// this caused some levels to simply not render
-	if (r_novis->integer || !tr.world->vis || tr.visClusters[tr.visIndex] == -1) {
-		for (i=0 ; i<tr.world->numnodes ; i++) {
-			if (tr.world->nodes[i].contents != CONTENTS_SOLID) {
-				tr.world->nodes[i].visCounts[tr.visIndex] = tr.visCounts[tr.visIndex];
-			}
-		}
-		return;
-	}
-
 	vis = R_ClusterPVS(tr.visClusters[tr.visIndex]);
 	
 	for (i=0,leaf=tr.world->nodes ; i<tr.world->numnodes ; i++, leaf++) {
@@ -754,7 +735,7 @@ static void R_MarkLeaves (void) {
 		}
 
 		// check general pvs
-		if ( !(vis[cluster>>3] & (1<<(cluster&7))) ) {
+		if ( vis && !(vis[cluster>>3] & (1<<(cluster&7))) ) {
 			continue;
 		}