From 381e53017de53a2a3f66ba96353bb0f3782c31ff Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Fri, 29 May 2020 00:44:13 +0200
Subject: [PATCH] - some hackery to make the camera textures in DN3D work
 again.

They depend on a deleted texture not writing to the depth buffer, but other parts in the engine like ROR surfaces depend on them writing a proper depth buffer value, so for now there is a global variable that allows to exclude a single tile from ever getting rendered.
---
 source/build/include/build.h    | 1 +
 source/build/src/polymost.cpp   | 6 +++++-
 source/duke3d/src/game.cpp      | 2 ++
 source/glbackend/gl_texture.cpp | 3 ++-
 source/rr/src/game.cpp          | 3 +++
 5 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/source/build/include/build.h b/source/build/include/build.h
index 33bfa7d66..76113d36d 100644
--- a/source/build/include/build.h
+++ b/source/build/include/build.h
@@ -1204,6 +1204,7 @@ int32_t engineLoadBoardV5V6(const char *filename, char fromwhere, vec3_t *dapos,
 # include "polymost.h"
 #endif
 
+extern int skiptile;
 
 static vec2_t const zerovec = { 0, 0 };
 
diff --git a/source/build/src/polymost.cpp b/source/build/src/polymost.cpp
index 3a65158e3..7fb1f4457 100644
--- a/source/build/src/polymost.cpp
+++ b/source/build/src/polymost.cpp
@@ -20,6 +20,7 @@ Ken Silverman's official web site: http://www.advsys.net/ken
 #include "flatvertices.h"
 #include "palettecontainer.h"
 #include "texturemanager.h"
+#include "gamecontrol.h"
 
 CVAR(Bool, hw_detailmapping, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
 CVAR(Bool, hw_glowmapping, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
@@ -314,9 +315,12 @@ static void polymost_updaterotmat(void)
 
 static void polymost_flatskyrender(vec2f_t const* const dpxy, int32_t const n, int32_t method, const vec2_16_t& tilesiz);
 
+// Hack for Duke's camera until I can find out why this behaves erratically.
+int skiptile = -1;
+
 static void polymost_drawpoly(vec2f_t const * const dpxy, int32_t const n, int32_t method, const vec2_16_t &tilesize)
 {
-    if (method == DAMETH_BACKFACECULL ||
+    if (method == DAMETH_BACKFACECULL || globalpicnum == skiptile ||
 #ifdef YAX_ENABLE
         g_nodraw ||
 #endif
diff --git a/source/duke3d/src/game.cpp b/source/duke3d/src/game.cpp
index ed3ee558c..5642a2970 100644
--- a/source/duke3d/src/game.cpp
+++ b/source/duke3d/src/game.cpp
@@ -5740,6 +5740,8 @@ int GameInterface::app_main()
 
     tileDelete(MIRROR);
 
+    skiptile = W_FORCEFIELD + 1;
+
     Gv_ResetSystemDefaults(); // called here to populate our fake tilesizx and tilesizy arrays presented to CON with sizes generated by dummytiles
 
     if (numplayers == 1 && boardfilename[0] != 0)
diff --git a/source/glbackend/gl_texture.cpp b/source/glbackend/gl_texture.cpp
index f739bdde8..52e765f05 100644
--- a/source/glbackend/gl_texture.cpp
+++ b/source/glbackend/gl_texture.cpp
@@ -91,7 +91,8 @@ FHardwareTexture* GLInstance::CreateIndexedTexture(FGameTexture* tex)
 
 FHardwareTexture* GLInstance::CreateTrueColorTexture(FGameTexture* tex, int palid, bool checkfulltransparency, bool rgb8bit)
 {
-	if (tex == TexMan.GameByIndex(0)) return nullptr;
+	if (tex == TexMan.GameByIndex(0)) 
+		return nullptr;
 	auto texbuffer = tex->GetTexture()->CreateTexBuffer(palid, checkfulltransparency? 0: CTF_ProcessData);
 	// Check if the texture is fully transparent. When creating a brightmap such textures can be discarded.
 	if (checkfulltransparency)
diff --git a/source/rr/src/game.cpp b/source/rr/src/game.cpp
index 7eb8130b8..9220cfddd 100644
--- a/source/rr/src/game.cpp
+++ b/source/rr/src/game.cpp
@@ -7130,6 +7130,9 @@ int GameInterface::app_main()
     G_PostLoadPalette();
 
     tileDelete(MIRROR);
+
+    skiptile = W_FORCEFIELD + 1;
+
     if (RR)
         tileDelete(0);
     if (RRRA)