brad/2744 handle shader errors (#3105)

* Partial solution to #2744 crash with better error handling.

Handles shader compile errors better, and should turn crash into an LL_ERRS assertion failure.
Strengthed more assertions and improved shader error line numbers

* Even more error handling to get a handle on crash #2744
* Improved GLSL correctness on Intel chips that lack OpenGL 4.6 support. #2744
* Removed non-working fallback code for gDeferredPostProgram
* Fixed incorrect llmax call

Author: brad-linden

indra/llrender/llglslshader.cpp

@@ -1046,7 +1046,7 @@ void LLGLSLShader::bind()
 {
     LL_PROFILE_ZONE_SCOPED_CATEGORY_SHADER;
 
-    llassert(mProgramObject != 0);
+    llassert_always(mProgramObject != 0);
 
     gGL.flush();
 
@@ -1069,6 +1069,9 @@ void LLGLSLShader::bind()
         LLShaderMgr::instance()->updateShaderUniforms(this);
         mUniformsDirty = false;
     }
+
+    llassert_always(sCurBoundShaderPtr != nullptr);
+    llassert_always(sCurBoundShader == mProgramObject);
 }
 
 void LLGLSLShader::bind(U8 variant)

indra/llrender/llrender.cpp

@@ -1569,7 +1569,8 @@ void LLRender::flush()
     if (mCount > 0)
     {
         LL_PROFILE_ZONE_SCOPED_CATEGORY_PIPELINE;
-        llassert(LLGLSLShader::sCurBoundShaderPtr != nullptr);
+        llassert_always(LLGLSLShader::sCurBoundShaderPtr != nullptr);
+
         if (!mUIOffset.empty())
         {
             sUICalls++;

indra/llrender/llshadermgr.cpp

@@ -559,17 +559,11 @@ GLuint LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shader_lev
         }
         else if (major_version == 3)
         {
-            if (minor_version < 10)
+            if (minor_version <= 29)
             {
-                shader_code_text[shader_code_count++] = strdup("#version 300\n");
-            }
-            else if (minor_version <= 19)
-            {
-                shader_code_text[shader_code_count++] = strdup("#version 310\n");
-            }
-            else if (minor_version <= 29)
-            {
-                shader_code_text[shader_code_count++] = strdup("#version 320\n");
+                // OpenGL 3.2 had GLSL version 1.50.  anything after that the version numbers match.
+                // https://www.khronos.org/opengl/wiki/Core_Language_(GLSL)#OpenGL_and_GLSL_versions
+                shader_code_text[shader_code_count++] = strdup("#version 150\n");
             }
             else
             {

indra/newview/app_settings/shaders/class1/deferred/CASF.glsl

@@ -1151,7 +1151,7 @@ vec3 linear_to_srgb(vec3 cl);
  AF3 ASignedF3(AF3 m){return ASatF3(m*AF3_(A_INFN_F));}
  AF4 ASignedF4(AF4 m){return ASatF4(m*AF4_(A_INFN_F));}
 //------------------------------------------------------------------------------------------------------------------------------
- AF1 AGtZeroF1(AF1 m){return ASatF1(m*AF1_(A_INFP_F));}
+// #2744 avoid constant overflow  AF1 AGtZeroF1(AF1 m){return ASatF1(m*AF1_(A_INFP_F));}
  AF2 AGtZeroF2(AF2 m){return ASatF2(m*AF2_(A_INFP_F));}
  AF3 AGtZeroF3(AF3 m){return ASatF3(m*AF3_(A_INFP_F));}
  AF4 AGtZeroF4(AF4 m){return ASatF4(m*AF4_(A_INFP_F));}

indra/newview/app_settings/shaders/class1/interface/radianceGenF.glsl

@@ -130,7 +130,7 @@ vec4 prefilterEnvMap(vec3 R)
     float totalWeight = 0.0;
     float envMapDim = float(textureSize(reflectionProbes, 0).s);
     float roughness = mipLevel/max_probe_lod;
-    int numSamples = max(int(PROBE_FILTER_SAMPLES*roughness), 1);
+    uint numSamples = uint(max(PROBE_FILTER_SAMPLES*roughness, 1));
 
     float numMips = max_probe_lod+1;
 

indra/newview/app_settings/shaders/class3/deferred/screenSpaceReflPostF.glsl

@@ -81,7 +81,7 @@ void main()
 
     vec4 collectedColor = vec4(0);
 
-    float w = tapScreenSpaceReflection(4, tc, pos, norm.xyz, collectedColor, diffuseMap, 0);
+    float w = tapScreenSpaceReflection(4, tc, pos, norm.xyz, collectedColor, diffuseMap, 0.f);
 
     collectedColor.rgb *= specCol.rgb;
 

indra/newview/llfeaturemanager.cpp

@@ -627,6 +627,21 @@ void LLFeatureManager::applyBaseMasks()
     if (gGLManager.mIsIntel)
     {
         maskFeatures("Intel");
+        if (gGLManager.mGLVersion < 4.59f)
+        {
+            // if we don't have OpenGL 4.6 on intel, set it to OpenGL 3.3
+            // we also want to trigger the GL3 fallbacks on these chipsets
+            // this is expected to be mainly pre-Haswell Intel HD Graphics 4X00 and 5X00.
+            // A lot of these chips claim 4.3 or 4.4 support, but don't seem to work.
+            // https://code.blender.org/2019/04/supported-gpus-in-blender-2-80/
+            // https://docs.blender.org/manual/en/latest/troubleshooting/gpu/windows/intel.html#legacy-intel-hd-4000-5000
+            // https://www.intel.com/content/www/us/en/support/articles/000005524/graphics.html
+            // this will disable things like reflection probes, HDR, FXAA and SMAA
+            gGLManager.mGLVersion = llmin(gGLManager.mGLVersion, 3.33f);
+            // and select GLSL version for OpenGL 3.3
+            gGLManager.mGLSLVersionMajor = 3;
+            gGLManager.mGLSLVersionMinor = 30;
+        }
     }
     if (gGLManager.mIsApple)
     {

indra/newview/llviewershadermgr.cpp

@@ -2539,7 +2539,14 @@ bool LLViewerShaderMgr::loadShadersDeferred()
         gCASProgram.mShaderFiles.push_back(make_pair("deferred/postDeferredNoTCV.glsl", GL_VERTEX_SHADER));
         gCASProgram.mShaderFiles.push_back(make_pair("deferred/CASF.glsl", GL_FRAGMENT_SHADER));
         gCASProgram.mShaderLevel = mShaderLevel[SHADER_DEFERRED];
-        gCASProgram.createShader();
+        success = gCASProgram.createShader();
+        // llassert(success);
+        if (!success)
+        {
+            LL_WARNS() << "Failed to create shader '" << gCASProgram.mName << "', disabling!" << LL_ENDL;
+            // continue as if this shader never happened
+            success = true;
+        }
     }
 
     if (success)

indra/newview/pipeline.cpp

@@ -1435,15 +1435,24 @@ void LLPipeline::createLUTBuffers()
 
     mPbrBrdfLut.allocate(512, 512, GL_RG16F);
     mPbrBrdfLut.bindTarget();
-    gDeferredGenBrdfLutProgram.bind();
-
-    gGL.begin(LLRender::TRIANGLE_STRIP);
-    gGL.vertex2f(-1, -1);
-    gGL.vertex2f(-1, 1);
-    gGL.vertex2f(1, -1);
-    gGL.vertex2f(1, 1);
-    gGL.end();
-    gGL.flush();
+
+    if (gDeferredGenBrdfLutProgram.isComplete())
+    {
+        gDeferredGenBrdfLutProgram.bind();
+        llassert_always(LLGLSLShader::sCurBoundShaderPtr != nullptr);
+
+        gGL.begin(LLRender::TRIANGLE_STRIP);
+        gGL.vertex2f(-1, -1);
+        gGL.vertex2f(-1, 1);
+        gGL.vertex2f(1, -1);
+        gGL.vertex2f(1, 1);
+        gGL.end();
+        gGL.flush();
+    }
+    else
+    {
+        LL_WARNS("Brad") << gDeferredGenBrdfLutProgram.mName << " failed to load, cannot be used!" << LL_ENDL;
+    }
 
     gDeferredGenBrdfLutProgram.unbind();
     mPbrBrdfLut.flush();