From 2b27cb0bbaf95d806337f3b95580524e655128f1 Mon Sep 17 00:00:00 2001
From: drfrag <drfrag666@hotmail.com>
Date: Wed, 4 Sep 2019 16:39:51 +0200
Subject: [PATCH] - Fill the gaps with the sky or ceiling texture.

---
 src/gl/scene/gl_bsp.cpp   | 11 +++++++++--
 src/gl/scene/gl_wall.h    |  2 +-
 src/gl/scene/gl_walls.cpp | 21 ++++++++++++++++++++-
 3 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/src/gl/scene/gl_bsp.cpp b/src/gl/scene/gl_bsp.cpp
index 382fe8496..f8236a2b3 100644
--- a/src/gl/scene/gl_bsp.cpp
+++ b/src/gl/scene/gl_bsp.cpp
@@ -77,7 +77,7 @@ void GLSceneDrawer::UnclipSubsector(subsector_t *sub)
 //
 //==========================================================================
 
-CVAR(Float, gl_line_distance_cull, 0.0, 0 /*CVAR_ARCHIVE|CVAR_GLOBALCONFIG*/) // this is deactivated, for now
+CVAR(Float, gl_line_distance_cull, 0.0, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 inline bool IsDistanceCulled(seg_t *line)
 {
@@ -138,7 +138,14 @@ void GLSceneDrawer::AddLine (seg_t *seg, bool portalclip)
 
 	uint8_t ispoly = uint8_t(seg->sidedef->Flags & WALLF_POLYOBJ);
 
-	if (IsDistanceCulled(seg)) { clipper.SafeAddClipRange(startAngle, endAngle); return; }
+	if (IsDistanceCulled(seg))
+	{
+		GLWall wall(this);
+		wall.sub = currentsubsector;
+		wall.Process(seg, seg->frontsector, seg->backsector, true);
+		clipper.SafeAddClipRange(startAngle, endAngle);
+		return;
+	}
 
 	if (!seg->backsector)
 	{
diff --git a/src/gl/scene/gl_wall.h b/src/gl/scene/gl_wall.h
index 4a4a04023..cdb561c4b 100644
--- a/src/gl/scene/gl_wall.h
+++ b/src/gl/scene/gl_wall.h
@@ -271,7 +271,7 @@ public:
 		mDrawer = drawer;
 	}
 
-	void Process(seg_t *seg, sector_t *frontsector, sector_t *backsector);
+	void Process(seg_t *seg, sector_t *frontsector, sector_t *backsector, bool isculled = false);
 	void ProcessLowerMiniseg(seg_t *seg, sector_t *frontsector, sector_t *backsector);
 	void Draw(int pass);
 
diff --git a/src/gl/scene/gl_walls.cpp b/src/gl/scene/gl_walls.cpp
index 107477d16..6e72c6c32 100644
--- a/src/gl/scene/gl_walls.cpp
+++ b/src/gl/scene/gl_walls.cpp
@@ -1425,7 +1425,7 @@ void GLWall::DoFFloorBlocks(seg_t * seg, sector_t * frontsector, sector_t * back
 // 
 //
 //==========================================================================
-void GLWall::Process(seg_t *seg, sector_t * frontsector, sector_t * backsector)
+void GLWall::Process(seg_t *seg, sector_t * frontsector, sector_t * backsector, bool isculled)
 {
 	vertex_t * v1, *v2;
 	float fch1;
@@ -1556,6 +1556,25 @@ void GLWall::Process(seg_t *seg, sector_t * frontsector, sector_t * backsector)
 		return;
 	}
 
+	if (isculled)
+	{
+		if (frontsector->GetTexture(sector_t::ceiling) == skyflatnum)
+		{
+			SkyNormal(frontsector, v1, v2);
+		}
+		else
+		{
+			gltexture = FMaterial::ValidateTexture(frontsector->GetTexture(sector_t::ceiling), false, true);
+			if (gltexture)
+			{
+				DoTexture(RENDERWALL_TOP, seg, true,
+					crefz, frefz,
+					fch1, fch2, ffh1, ffh2, 0);
+			}
+		}
+		return;
+	}
+
 	//return;
 	// [GZ] 3D middle textures are necessarily two-sided, even if they lack the explicit two-sided flag
 	if (!backsector || !(seg->linedef->flags&(ML_TWOSIDED | ML_3DMIDTEX))) // one sided