Merge remote-tracking branch 'remotes/origin/DRTVWR-546' into SL-17005

17 files changed, 273 insertions, 46 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/alphaF.glsl b/indra/newview/app_settings/shaders/class1/deferred/alphaF.glsl
index d3a05c34c0..638a0f4e15 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/alphaF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/alphaF.glsl
@@ -215,6 +215,11 @@ void main()
     float final_alpha = diffuse_linear.a;
 
 #ifdef USE_VERTEX_COLOR
+    if (vertex_color.a <= 0.0)
+    { // TODO: figure out how to get invisible faces out of 
+        // render batches without breaking glow
+        discard;
+    }
     final_alpha *= vertex_color.a;
     diffuse_srgb.rgb *= vertex_color.rgb;
     diffuse_linear.rgb = srgb_to_linear(diffuse_srgb.rgb);
@@ -308,7 +313,7 @@ vec3 post_atmo = color.rgb;
 #endif // WATER_FOG
 
 #endif
-    
+
     frag_color = color;
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/objects/previewPhysicsF.glsl b/indra/newview/app_settings/shaders/class1/objects/previewPhysicsF.glsl
new file mode 100644
index 0000000000..3a5e6fdf7c
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/objects/previewPhysicsF.glsl
@@ -0,0 +1,42 @@
+/** 
+ * @file previewPhysicsF.glsl
+ *
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2022, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifdef DEFINE_GL_FRAGCOLOR
+out vec4 frag_color;
+#else
+#define frag_color gl_FragColor
+#endif
+
+uniform sampler2D diffuseMap;
+uniform vec4 color;
+
+VARYING vec2 vary_texcoord0;
+
+//====================================================================================================
+
+void main()
+{
+    frag_color = texture2D(diffuseMap,vary_texcoord0.xy) * color;
+}
diff --git a/indra/newview/app_settings/shaders/class1/objects/previewPhysicsV.glsl b/indra/newview/app_settings/shaders/class1/objects/previewPhysicsV.glsl
new file mode 100644
index 0000000000..913dec83bd
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/objects/previewPhysicsV.glsl
@@ -0,0 +1,42 @@
+/** 
+ * @file previewPhysicsV.glsl
+ *
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2022, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+uniform mat4 texture_matrix0;
+uniform mat4 modelview_matrix;
+uniform mat4 modelview_projection_matrix;
+
+ATTRIBUTE vec3 position;
+ATTRIBUTE vec2 texcoord0;
+
+VARYING vec2 vary_texcoord0;
+
+//====================================================================================================
+
+void main()
+{
+	//transform vertex
+	gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0);
+	vary_texcoord0 = (texture_matrix0 * vec4(texcoord0,0,1)).xy;
+}
diff --git a/indra/newview/llavatarrenderinfoaccountant.cpp b/indra/newview/llavatarrenderinfoaccountant.cpp
index ca83afb5ab..140b9e6f36 100644
--- a/indra/newview/llavatarrenderinfoaccountant.cpp
+++ b/indra/newview/llavatarrenderinfoaccountant.cpp
@@ -82,7 +82,15 @@ void LLAvatarRenderInfoAccountant::avatarRenderInfoGetCoro(std::string url, U64
 
     LLSD result = httpAdapter->getAndSuspend(httpRequest, url);
 
-    LLViewerRegion * regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+    LLWorld *world_inst = LLWorld::getInstance();
+    if (!world_inst)
+    {
+        LL_WARNS("AvatarRenderInfoAccountant") << "Avatar render weight info received but world no longer exists "
+            << regionHandle << LL_ENDL;
+        return;
+    }
+
+    LLViewerRegion * regionp = world_inst->getRegionFromHandle(regionHandle);
     if (!regionp)
     {
         LL_WARNS("AvatarRenderInfoAccountant") << "Avatar render weight info received but region not found for " 
@@ -183,7 +191,15 @@ void LLAvatarRenderInfoAccountant::avatarRenderInfoReportCoro(std::string url, U
         httpAdapter(new LLCoreHttpUtil::HttpCoroutineAdapter("AvatarRenderInfoAccountant", httpPolicy));
     LLCore::HttpRequest::ptr_t httpRequest(new LLCore::HttpRequest);
 
-    LLViewerRegion * regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+    LLWorld *world_inst = LLWorld::getInstance();
+    if (!world_inst)
+    {
+        LL_WARNS("AvatarRenderInfoAccountant") << "Avatar render weight calculation but world no longer exists "
+            << regionHandle << LL_ENDL;
+        return;
+    }
+
+    LLViewerRegion * regionp = world_inst->getRegionFromHandle(regionHandle);
     if (!regionp)
     {
         LL_WARNS("AvatarRenderInfoAccountant") << "Avatar render weight calculation but region not found for "
@@ -239,9 +255,18 @@ void LLAvatarRenderInfoAccountant::avatarRenderInfoReportCoro(std::string url, U
     report[KEY_AGENTS] = agents;
 
     regionp = NULL;
+    world_inst = NULL;
     LLSD result = httpAdapter->postAndSuspend(httpRequest, url, report);
 
-    regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+    world_inst = LLWorld::getInstance();
+    if (!world_inst)
+    {
+        LL_WARNS("AvatarRenderInfoAccountant") << "Avatar render weight POST result but world no longer exists "
+            << regionHandle << LL_ENDL;
+        return;
+    }
+
+    regionp = world_inst->getRegionFromHandle(regionHandle);
     if (!regionp)
     {
         LL_INFOS("AvatarRenderInfoAccountant") << "Avatar render weight POST result received but region not found for "
diff --git a/indra/newview/llchathistory.cpp b/indra/newview/llchathistory.cpp
index c110e0d815..cdf82c77c1 100644
--- a/indra/newview/llchathistory.cpp
+++ b/indra/newview/llchathistory.cpp
@@ -752,7 +752,7 @@ public:
 		if ( chat.mSourceType == CHAT_SOURCE_OBJECT)
 		{
 			std::string slurl = args["slurl"].asString();
-			if (slurl.empty())
+			if (slurl.empty() && LLWorld::instanceExists())
 			{
 				LLViewerRegion *region = LLWorld::getInstance()->getRegionFromPosAgent(chat.mPosAgent);
 				if(region)
diff --git a/indra/newview/lldrawpool.cpp b/indra/newview/lldrawpool.cpp
index faa5f71da4..5c291b69fc 100644
--- a/indra/newview/lldrawpool.cpp
+++ b/indra/newview/lldrawpool.cpp
@@ -451,7 +451,7 @@ void LLRenderPass::pushRiggedBatches(U32 type, U32 mask, BOOL texture, BOOL batc
         LLDrawInfo* pparams = *i;
         if (pparams)
         {
-            if (lastAvatar != pparams->mAvatar || lastMeshId != pparams->mSkinInfo->mHash)
+            if (pparams->mAvatar.notNull() && (lastAvatar != pparams->mAvatar || lastMeshId != pparams->mSkinInfo->mHash))
             {
                 uploadMatrixPalette(*pparams);
                 lastAvatar = pparams->mAvatar;
diff --git a/indra/newview/lldrawpoolalpha.cpp b/indra/newview/lldrawpoolalpha.cpp
index 2bf8e9b911..5656eb1471 100644
--- a/indra/newview/lldrawpoolalpha.cpp
+++ b/indra/newview/lldrawpoolalpha.cpp
@@ -228,8 +228,8 @@ void LLDrawPoolAlpha::forwardRender(bool rigged)
     //enable writing to alpha for emissive effects
     gGL.setColorMask(true, true);
 
-    bool write_depth = rigged
-        || LLDrawPoolWater::sSkipScreenCopy
+    bool write_depth = rigged || 
+        LLDrawPoolWater::sSkipScreenCopy
         // we want depth written so that rendered alpha will
         // contribute to the alpha mask used for impostors
         || LLPipeline::sImpostorRenderAlphaDepthPass;
@@ -484,6 +484,7 @@ void LLDrawPoolAlpha::renderEmissives(U32 mask, std::vector<LLDrawInfo*>& emissi
 
 void LLDrawPoolAlpha::renderRiggedEmissives(U32 mask, std::vector<LLDrawInfo*>& emissives)
 {
+    LLGLDepthTest depth(GL_TRUE, GL_FALSE); //disable depth writes since "emissive" is additive so sorting doesn't matter
     LLGLSLShader* shader = emissive_shader->mRiggedVariant;
     shader->bind();
     shader->uniform1f(LLShaderMgr::EMISSIVE_BRIGHTNESS, 1.f);
diff --git a/indra/newview/llface.h b/indra/newview/llface.h
index 79f50f2273..aa00c9d052 100644
--- a/indra/newview/llface.h
+++ b/indra/newview/llface.h
@@ -143,7 +143,7 @@ public:
 	LLViewerObject*	getViewerObject()	const	{ return mVObjp; }
 	S32				getLOD()			const	{ return mVObjp.notNull() ? mVObjp->getLOD() : 0; }
 	void			setPoolType(U32 type)		{ mPoolType = type; }
-	S32				getTEOffset()				{ return mTEOffset; }
+	S32				getTEOffset()       const   { return mTEOffset; }
 	LLViewerTexture*	getTexture(U32 ch = LLRender::DIFFUSE_MAP) const;
 
 	void			setViewerObject(LLViewerObject* object);
@@ -233,6 +233,12 @@ public:
 	void	notifyAboutCreatingTexture(LLViewerTexture *texture);
 	void	notifyAboutMissingAsset(LLViewerTexture *texture);
 
+    // used to preserve draw order of faces that are batched together. 
+    // Allows content creators to manipulate linked sets and face ordering 
+    // for consistent alpha sorting results, particularly for rigged attachments
+    void setDrawOrderIndex(U32 index) { mDrawOrderIndex = index; }
+    U32 getDrawOrderIndex() const { return mDrawOrderIndex; }
+
 public: //aligned members
 	LLVector4a		mExtents[2];
 
@@ -305,6 +311,7 @@ private:
 	bool        mHasMedia ;
 	bool        mIsMediaAllowed;
 
+    U32 mDrawOrderIndex = 0; // see setDrawOrderIndex
 	
 protected:
 	static BOOL	sSafeRenderSelect;
diff --git a/indra/newview/llfeaturemanager.cpp b/indra/newview/llfeaturemanager.cpp
index 3240f169b3..e934041e2e 100644
--- a/indra/newview/llfeaturemanager.cpp
+++ b/indra/newview/llfeaturemanager.cpp
@@ -381,7 +381,10 @@ F32 gpu_benchmark();
 
 F32 logExceptionBenchmark()
 {
-    // Todo: make a wrapper/class for SEH exceptions
+    // FIXME: gpu_benchmark uses many C++ classes on the stack to control state.
+    //  SEH exceptions with our current exception handling options do not call 
+    //  destructors for these classes, resulting in an undefined state should
+    //  this handler be invoked.  
     F32 gbps = -1;
     __try
     {
@@ -389,6 +392,9 @@ F32 logExceptionBenchmark()
     }
     __except (msc_exception_filter(GetExceptionCode(), GetExceptionInformation()))
     {
+        // HACK - ensure that profiling is disabled
+        LLGLSLShader::finishProfile(false);
+
         // convert to C++ styled exception
         char integer_string[32];
         sprintf(integer_string, "SEH, code: %lu\n", GetExceptionCode());
diff --git a/indra/newview/llmodelpreview.cpp b/indra/newview/llmodelpreview.cpp
index b60fabb01b..c7f56de4ed 100644
--- a/indra/newview/llmodelpreview.cpp
+++ b/indra/newview/llmodelpreview.cpp
@@ -3285,6 +3285,14 @@ BOOL LLModelPreview::render()
 
                                 if (!physics.mMesh.empty())
                                 { //render hull instead of mesh
+                                    // SL-16993 physics.mMesh[i].mNormals were being used to light the exploded
+                                    // analyzed physics shape but the drawArrays() interface changed
+                                    //  causing normal data <0,0,0> to be passed to the shader.
+                                    // The Phyics Preview shader uses plain vertex coloring so the physics hull is full lit.
+                                    // We could also use interface/ui shaders.
+                                    gObjectPreviewProgram.unbind();
+                                    gPhysicsPreviewProgram.bind();
+
                                     for (U32 i = 0; i < physics.mMesh.size(); ++i)
                                     {
                                         if (explode > 0.f)
@@ -3312,6 +3320,9 @@ BOOL LLModelPreview::render()
                                             gGL.popMatrix();
                                         }
                                     }
+
+                                    gPhysicsPreviewProgram.unbind();
+                                    gObjectPreviewProgram.bind();
                                 }
                             }
                         }
diff --git a/indra/newview/llstartup.cpp b/indra/newview/llstartup.cpp
index 94bafcb612..bb6ad5d8fb 100644
--- a/indra/newview/llstartup.cpp
+++ b/indra/newview/llstartup.cpp
@@ -310,6 +310,12 @@ void update_texture_fetch()
 	LLAppViewer::getImageDecodeThread()->update(1); // unpauses the image thread
 	LLAppViewer::getTextureFetch()->update(1); // unpauses the texture fetch thread
 	gTextureList.updateImages(0.10f);
+
+    if (LLImageGLThread::sEnabled)
+    {
+        std::shared_ptr<LL::WorkQueue> main_queue = LL::WorkQueue::getInstance("mainloop");
+        main_queue->runFor(std::chrono::milliseconds(1));
+    }
 }
 
 void set_flags_and_update_appearance()
@@ -1518,7 +1524,11 @@ bool idle_startup()
 		display_startup();
 
 		LL_DEBUGS("AppInit") << "Decoding images..." << LL_ENDL;
-		// For all images pre-loaded into viewer cache, decode them.
+		// For all images pre-loaded into viewer cache, init
+        // priorities and fetching using decodeAllImages.
+        // Most of the fetching and decoding likely to be done
+        // by update_texture_fetch() later, while viewer waits.
+        //
 		// Need to do this AFTER we init the sky
 		const S32 DECODE_TIME_SEC = 2;
 		for (int i = 0; i < DECODE_TIME_SEC; i++)
diff --git a/indra/newview/llviewerregion.cpp b/indra/newview/llviewerregion.cpp
index 27fbf39673..501148a112 100644
--- a/indra/newview/llviewerregion.cpp
+++ b/indra/newview/llviewerregion.cpp
@@ -266,7 +266,14 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCoro(U64 regionHandle)
             return;
         }
 
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        LLWorld *world_inst = LLWorld::getInstance(); // Not a singleton!
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Attempting to get capabilities, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "Capabilities") << "Attempting to get capabilities for region that no longer exists!" << LL_ENDL;
@@ -314,6 +321,7 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCoro(U64 regionHandle)
 
         regionp = NULL;
         impl = NULL;
+        world_inst = NULL;
         result = httpAdapter->postAndSuspend(httpRequest, url, capabilityNames);
 
         if (STATE_WORLD_INIT > LLStartUp::getStartupState())
@@ -327,7 +335,14 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCoro(U64 regionHandle)
             return;
         }
 
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        world_inst = LLWorld::getInstance();
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Received capabilities, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "Capabilities") << "Received capabilities for region that no longer exists!" << LL_ENDL;
@@ -411,7 +426,14 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCompleteCoro(U64 regionHandle)
     // This loop is used for retrying a capabilities request.
     do
     {
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        LLWorld *world_inst = LLWorld::getInstance(); // Not a singleton!
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Attempting to get capabilities, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "Capabilities") << "Attempting to get capabilities for region that no longer exists!" << LL_ENDL;
@@ -434,6 +456,7 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCompleteCoro(U64 regionHandle)
         LL_INFOS("AppInit", "Capabilities") << "Requesting second Seed from " << url << " for region " << regionp->getRegionID() << LL_ENDL;
 
         regionp = NULL;
+        world_inst = NULL;
         result = httpAdapter->postAndSuspend(httpRequest, url, capabilityNames);
 
         LLSD httpResults = result["http_result"];
@@ -449,7 +472,14 @@ void LLViewerRegionImpl::requestBaseCapabilitiesCompleteCoro(U64 regionHandle)
             break;
         }
 
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        world_inst = LLWorld::getInstance();
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Received capabilities, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "Capabilities") << "Received capabilities for region that no longer exists!" << LL_ENDL;
@@ -533,7 +563,14 @@ void LLViewerRegionImpl::requestSimulatorFeatureCoro(std::string url, U64 region
             break;
         }
 
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        LLWorld *world_inst = LLWorld::getInstance(); // Not a singleton!
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Attempting to request Sim Feature, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "SimulatorFeatures") << "Attempting to request Sim Feature for region that no longer exists!" << LL_ENDL;
@@ -541,6 +578,7 @@ void LLViewerRegionImpl::requestSimulatorFeatureCoro(std::string url, U64 region
         }
 
         regionp = NULL;
+        world_inst = NULL;
         LLSD result = httpAdapter->getAndSuspend(httpRequest, url);
 
         LLSD httpResults = result["http_result"];
@@ -559,7 +597,14 @@ void LLViewerRegionImpl::requestSimulatorFeatureCoro(std::string url, U64 region
         // remove the http_result from the llsd
         result.erase("http_result");
 
-        regionp = LLWorld::getInstance()->getRegionFromHandle(regionHandle);
+        world_inst = LLWorld::getInstance();
+        if (!world_inst)
+        {
+            LL_WARNS("AppInit", "Capabilities") << "Attempting to request Sim Feature, but world no longer exists!" << LL_ENDL;
+            return;
+        }
+
+        regionp = world_inst->getRegionFromHandle(regionHandle);
         if (!regionp) //region was removed
         {
             LL_WARNS("AppInit", "SimulatorFeatures") << "Attempting to set Sim Feature for region that no longer exists!" << LL_ENDL;
@@ -2092,7 +2137,14 @@ public:
 		const LLSD& input) const
 	{
 		LLHost host(input["sender"].asString());
-		LLViewerRegion* region = LLWorld::getInstance()->getRegion(host);
+
+        LLWorld *world_inst = LLWorld::getInstance(); // Not a singleton!
+        if (!world_inst)
+        {
+            return;
+        }
+
+		LLViewerRegion* region = world_inst->getRegion(host);
 		if( !region )
 		{
 			return;
diff --git a/indra/newview/llviewershadermgr.cpp b/indra/newview/llviewershadermgr.cpp
index c97b1d914b..a8e0f576ca 100644
--- a/indra/newview/llviewershadermgr.cpp
+++ b/indra/newview/llviewershadermgr.cpp
@@ -102,6 +102,7 @@ LLGLSLShader        gSkinnedObjectSimpleProgram;
 LLGLSLShader		gObjectSimpleImpostorProgram;
 LLGLSLShader        gSkinnedObjectSimpleImpostorProgram;
 LLGLSLShader		gObjectPreviewProgram;
+LLGLSLShader        gPhysicsPreviewProgram;
 LLGLSLShader		gObjectSimpleWaterProgram;
 LLGLSLShader        gSkinnedObjectSimpleWaterProgram;
 LLGLSLShader		gObjectSimpleAlphaMaskProgram;
@@ -758,6 +759,7 @@ void LLViewerShaderMgr::unloadShaders()
 	gObjectSimpleImpostorProgram.unload();
     gSkinnedObjectSimpleImpostorProgram.unload();
 	gObjectPreviewProgram.unload();
+    gPhysicsPreviewProgram.unload();
 	gImpostorProgram.unload();
 	gObjectSimpleAlphaMaskProgram.unload();
     gSkinnedObjectSimpleAlphaMaskProgram.unload();
@@ -3023,6 +3025,24 @@ BOOL LLViewerShaderMgr::loadShadersObject()
 
 	if (success)
 	{
+		gPhysicsPreviewProgram.mName = "Preview Physics Shader";
+		gPhysicsPreviewProgram.mFeatures.calculatesLighting = false;
+		gPhysicsPreviewProgram.mFeatures.calculatesAtmospherics = false;
+		gPhysicsPreviewProgram.mFeatures.hasGamma = false;
+		gPhysicsPreviewProgram.mFeatures.hasAtmospherics = false;
+		gPhysicsPreviewProgram.mFeatures.hasLighting = false;
+		gPhysicsPreviewProgram.mFeatures.mIndexedTextureChannels = 0;
+		gPhysicsPreviewProgram.mFeatures.disableTextureIndex = true;
+		gPhysicsPreviewProgram.mShaderFiles.clear();
+		gPhysicsPreviewProgram.mShaderFiles.push_back(make_pair("objects/previewPhysicsV.glsl", GL_VERTEX_SHADER_ARB));
+		gPhysicsPreviewProgram.mShaderFiles.push_back(make_pair("objects/previewPhysicsF.glsl", GL_FRAGMENT_SHADER_ARB));
+		gPhysicsPreviewProgram.mShaderLevel = mShaderLevel[SHADER_OBJECT];
+		success = gPhysicsPreviewProgram.createShader(NULL, NULL);
+		gPhysicsPreviewProgram.mFeatures.hasLighting = false;
+	}
+
+	if (success)
+	{
 		gObjectSimpleProgram.mName = "Simple Shader";
 		gObjectSimpleProgram.mFeatures.calculatesLighting = true;
 		gObjectSimpleProgram.mFeatures.calculatesAtmospherics = true;
diff --git a/indra/newview/llviewershadermgr.h b/indra/newview/llviewershadermgr.h
index 297cfb6e68..93bb29a355 100644
--- a/indra/newview/llviewershadermgr.h
+++ b/indra/newview/llviewershadermgr.h
@@ -181,6 +181,7 @@ extern LLGLSLShader			gOneTextureNoColorProgram;
 extern LLGLSLShader			gObjectSimpleProgram;
 extern LLGLSLShader			gObjectSimpleImpostorProgram;
 extern LLGLSLShader			gObjectPreviewProgram;
+extern LLGLSLShader			gPhysicsPreviewProgram;
 extern LLGLSLShader			gObjectSimpleAlphaMaskProgram;
 extern LLGLSLShader			gObjectSimpleWaterProgram;
 extern LLGLSLShader			gObjectSimpleWaterAlphaMaskProgram;
diff --git a/indra/newview/llviewerstats.cpp b/indra/newview/llviewerstats.cpp
index d87afa9a41..71526e5e8c 100644
--- a/indra/newview/llviewerstats.cpp
+++ b/indra/newview/llviewerstats.cpp
@@ -389,8 +389,12 @@ void update_statistics()
 	gTransferManager.resetTransferBitsIn(LLTCT_ASSET);
 
 	sample(LLStatViewer::VISIBLE_AVATARS, LLVOAvatar::sNumVisibleAvatars);
-	LLWorld::getInstance()->updateNetStats();
-	LLWorld::getInstance()->requestCacheMisses();
+    LLWorld *world = LLWorld::getInstance(); // not LLSingleton
+    if (world)
+    {
+        world->updateNetStats();
+        world->requestCacheMisses();
+    }
 	
 	// Reset all of these values.
 	gVLManager.resetBitCounts();
diff --git a/indra/newview/llviewertexturelist.cpp b/indra/newview/llviewertexturelist.cpp
index 66e113b45c..2a88d9314b 100644
--- a/indra/newview/llviewertexturelist.cpp
+++ b/indra/newview/llviewertexturelist.cpp
@@ -1219,6 +1219,7 @@ void LLViewerTextureList::decodeAllImages(F32 max_time)
 		LLViewerFetchedTexture* imagep = *iter++;
 		imagep->updateFetch();
 	}
+    std::shared_ptr<LL::WorkQueue> main_queue = LLImageGLThread::sEnabled ? LL::WorkQueue::getInstance("mainloop") : NULL;
 	// Run threads
 	S32 fetch_pending = 0;
 	while (1)
@@ -1226,6 +1227,13 @@ void LLViewerTextureList::decodeAllImages(F32 max_time)
 		LLAppViewer::instance()->getTextureCache()->update(1); // unpauses the texture cache thread
 		LLAppViewer::instance()->getImageDecodeThread()->update(1); // unpauses the image thread
 		fetch_pending = LLAppViewer::instance()->getTextureFetch()->update(1); // unpauses the texture fetch thread
+
+        if (LLImageGLThread::sEnabled)
+        {
+            main_queue->runFor(std::chrono::milliseconds(1));
+            fetch_pending += main_queue->size();
+        }
+
 		if (fetch_pending == 0 || timer.getElapsedTimeF32() > max_time)
 		{
 			break;
diff --git a/indra/newview/llvovolume.cpp b/indra/newview/llvovolume.cpp
index f8728a5ab7..f18f6b1116 100644
--- a/indra/newview/llvovolume.cpp
+++ b/indra/newview/llvovolume.cpp
@@ -5467,6 +5467,7 @@ static inline void add_face(T*** list, U32* count, T* face)
     {
         if (count[1] < MAX_FACE_COUNT)
         {
+            face->setDrawOrderIndex(count[1]);
             list[1][count[1]++] = face;
         }
     }
@@ -5474,6 +5475,7 @@ static inline void add_face(T*** list, U32* count, T* face)
     {
         if (count[0] < MAX_FACE_COUNT)
         {
+            face->setDrawOrderIndex(count[0]);
             list[0][count[0]++] = face;
         }
     }
@@ -6088,7 +6090,7 @@ void LLVolumeGeometryManager::rebuildMesh(LLSpatialGroup* group)
 	} 
 }
 
-struct CompareBatchBreakerModified
+struct CompareBatchBreaker
 {
 	bool operator()(const LLFace* const& lhs, const LLFace* const& rhs)
 	{
@@ -6103,18 +6105,23 @@ struct CompareBatchBreakerModified
 		{
 			return lte->getFullbright() < rte->getFullbright();
 		}
-		else if (LLPipeline::sRenderDeferred && lte->getMaterialParams() != rte->getMaterialParams())
-		{
-			return lte->getMaterialParams() < rte->getMaterialParams();
-		}
-		else if (LLPipeline::sRenderDeferred && (lte->getMaterialParams() == rte->getMaterialParams()) && (lte->getShiny() != rte->getShiny()))
+        else if (LLPipeline::sRenderDeferred && lte->getMaterialID() != rte->getMaterialID())
+        {
+            return lte->getMaterialID() < rte->getMaterialID();
+        }
+		else if (lte->getShiny() != rte->getShiny())
 		{
 			return lte->getShiny() < rte->getShiny();
 		}
-		else
+        else if (lhs->getTexture() != rhs->getTexture())
 		{
 			return lhs->getTexture() < rhs->getTexture();
 		}
+        else 
+        {
+            // all else being equal, maintain consistent draw order
+            return lhs->getDrawOrderIndex() < rhs->getDrawOrderIndex();
+        }
 	}
 };
 
@@ -6122,9 +6129,6 @@ struct CompareBatchBreakerRigged
 {
     bool operator()(const LLFace* const& lhs, const LLFace* const& rhs)
     {
-        const LLTextureEntry* lte = lhs->getTextureEntry();
-        const LLTextureEntry* rte = rhs->getTextureEntry();
-
         if (lhs->mAvatar != rhs->mAvatar)
         {
             return lhs->mAvatar < rhs->mAvatar;
@@ -6133,23 +6137,12 @@ struct CompareBatchBreakerRigged
         {
             return lhs->mSkinInfo->mHash < rhs->mSkinInfo->mHash;
         }
-        else if (lhs->getTexture() != rhs->getTexture())
-        {
-            return lhs->getTexture() < rhs->getTexture();
-        }
-        else if (lte->getBumpmap() != rte->getBumpmap())
-        {
-            return lte->getBumpmap() < rte->getBumpmap();
-        }
-        else if (LLPipeline::sRenderDeferred && lte->getMaterialID() != rte->getMaterialID())
-        {
-            return lte->getMaterialID() < rte->getMaterialID();
-        }
-        else // if (LLPipeline::sRenderDeferred && (lte->getMaterialParams() == rte->getMaterialParams()) && (lte->getShiny() != rte->getShiny()))
+        else
         {
-            return lte->getShiny() < rte->getShiny();
+            // "inherit" non-rigged behavior
+            CompareBatchBreaker comp;
+            return comp(lhs, rhs);
         }
-        
     }
 };
 
@@ -6198,7 +6191,7 @@ U32 LLVolumeGeometryManager::genDrawInfo(LLSpatialGroup* group, U32 mask, LLFace
         else if (!distance_sort)
         {
             //sort faces by things that break batches, not including avatar and mesh id
-            std::sort(faces, faces + face_count, CompareBatchBreakerModified());
+            std::sort(faces, faces + face_count, CompareBatchBreaker());
         }
 		else
 		{