Merge pull request #641 from chaoc/passthrough

Add support for SPV_NV_geometry_shader_passthrough

glslang/Include/Types.h

@@ -599,6 +599,9 @@ public:
         layoutFormat = ElfNone;
 
         layoutPushConstant = false;
+#ifdef NV_EXTENSIONS
+        layoutPassthrough = false;
+#endif
     }
     bool hasLayout() const
     {
@@ -652,6 +655,10 @@ public:
 
     bool layoutPushConstant;
 
+#ifdef NV_EXTENSIONS
+    bool layoutPassthrough;
+#endif
+
     bool hasUniformLayout() const
     {
         return hasMatrix() ||
@@ -1537,6 +1544,12 @@ public:
                 if (qualifier.layoutPushConstant)
                     p += snprintf(p, end - p, "push_constant ");
 
+#ifdef NV_EXTENSIONS
+                if (qualifier.layoutPassthrough)
+                    p += snprintf(p, end - p, "passthrough ");
+#endif
+
+
                 p += snprintf(p, end - p, ") ");
             }
         }

glslang/MachineIndependent/ParseHelper.cpp

@@ -604,7 +604,11 @@ void TParseContext::fixIoArraySize(const TSourceLoc& loc, TType& type)
 void TParseContext::ioArrayCheck(const TSourceLoc& loc, const TType& type, const TString& identifier)
 {
     if (! type.isArray() && ! symbolTable.atBuiltInLevel()) {
-        if (type.getQualifier().isArrayedIo(language))
+        if (type.getQualifier().isArrayedIo(language)
+#ifdef NV_EXTENSIONS
+            && !type.getQualifier().layoutPassthrough
+#endif
+           )
             error(loc, "type must be an array:", type.getStorageQualifierString(), identifier.c_str());
     }
 }
@@ -3459,6 +3463,20 @@ void TParseContext::redeclareBuiltinBlock(const TSourceLoc& loc, TTypeList& newT
     //  - remove unused members
     //  - ensure remaining qualifiers/types match
     TType& type = block->getWritableType();
+
+#ifdef NV_EXTENSIONS
+    // if gl_PerVertex is redeclared for the purpose of passing through "gl_Position"
+    // for passthrough purpose, the redclared block should have the same qualifers as
+    // the current one
+    if (currentBlockQualifier.layoutPassthrough)
+    {
+        type.getQualifier().layoutPassthrough = currentBlockQualifier.layoutPassthrough;
+        type.getQualifier().storage = currentBlockQualifier.storage;
+        type.getQualifier().layoutStream = currentBlockQualifier.layoutStream;
+        type.getQualifier().layoutXfbBuffer = currentBlockQualifier.layoutXfbBuffer;
+    }
+#endif
+
     TTypeList::iterator member = type.getWritableStruct()->begin();
     size_t numOriginalMembersFound = 0;
     while (member != type.getStruct()->end()) {
@@ -3928,6 +3946,14 @@ void TParseContext::setLayoutQualifier(const TSourceLoc& loc, TPublicType& publi
                 publicType.shaderQualifiers.geometry = ElgTriangleStrip;
                 return;
             }
+#ifdef NV_EXTENSIONS
+            if (id == "passthrough") {
+               requireExtensions(loc, 1, &E_SPV_NV_geometry_shader_passthrough, "geometry shader passthrough");
+               publicType.qualifier.layoutPassthrough = true;
+               intermediate.setGeoPassthroughEXT();
+               return;
+            }
+#endif
         } else {
             assert(language == EShLangTessEvaluation);
 
@@ -4328,6 +4354,11 @@ void TParseContext::mergeObjectLayoutQualifiers(TQualifier& dst, const TQualifie
 
         if (src.layoutPushConstant)
             dst.layoutPushConstant = true;
+
+#ifdef NV_EXTENSIONS
+        if (src.layoutPassthrough)
+            dst.layoutPassthrough = true;
+#endif
     }
 }
 

glslang/MachineIndependent/Versions.cpp

@@ -197,6 +197,7 @@ void TParseVersions::initializeExtensionBehavior()
 
 #ifdef NV_EXTENSIONS 
     extensionBehavior[E_GL_NV_sample_mask_override_coverage]         = EBhDisable;
+    extensionBehavior[E_SPV_NV_geometry_shader_passthrough]          = EBhDisable;
 #endif
 
     // AEP
@@ -309,6 +310,7 @@ void TParseVersions::getPreamble(std::string& preamble)
 
 #ifdef NV_EXTENSIONS 
             "#define GL_NV_sample_mask_override_coverage 1\n"
+            "#define GL_NV_geometry_shader_passthrough 1\n"
 #endif
             ;
     }

glslang/MachineIndependent/Versions.h

@@ -144,6 +144,7 @@ const char* const E_GL_AMD_gpu_shader_half_float                = "GL_AMD_gpu_sh
 #endif
 #ifdef NV_EXTENSIONS
 const char* const E_GL_NV_sample_mask_override_coverage = "GL_NV_sample_mask_override_coverage";
+const char* const E_SPV_NV_geometry_shader_passthrough = "GL_NV_geometry_shader_passthrough";
 #endif
 
 // AEP

glslang/MachineIndependent/linkValidate.cpp

@@ -469,9 +469,17 @@ void TIntermediate::finalCheck(TInfoSink& infoSink, bool keepUncalled)
     case EShLangGeometry:
         if (inputPrimitive == ElgNone)
             error(infoSink, "At least one shader must specify an input layout primitive");
-        if (outputPrimitive == ElgNone)
+        if (outputPrimitive == ElgNone
+#ifdef NV_EXTENSIONS
+            && !getGeoPassthroughEXT()
+#endif
+            )
             error(infoSink, "At least one shader must specify an output layout primitive");
-        if (vertices == TQualifier::layoutNotSet)
+        if (vertices == TQualifier::layoutNotSet
+#ifdef NV_EXTENSIONS
+            && !getGeoPassthroughEXT()
+#endif
+           )
             error(infoSink, "At least one shader must specify a layout(max_vertices = value)");
         break;
     case EShLangFragment:

glslang/MachineIndependent/localintermediate.h

@@ -153,6 +153,7 @@ public:
         flattenUniformArrays(false),
 #ifdef NV_EXTENSIONS 
         layoutOverrideCoverage(false),
+        geoPassthroughEXT(false),
 #endif
         useUnknownFormat(false)
     {
@@ -393,6 +394,8 @@ public:
 #ifdef NV_EXTENSIONS 
     void setLayoutOverrideCoverage() { layoutOverrideCoverage = true; }
     bool getLayoutOverrideCoverage() const { return layoutOverrideCoverage; }
+    void setGeoPassthroughEXT() { geoPassthroughEXT = true; }
+    bool getGeoPassthroughEXT() const { return geoPassthroughEXT; }
 #endif
 
 protected:
@@ -457,6 +460,7 @@ protected:
 
 #ifdef NV_EXTENSIONS 
     bool layoutOverrideCoverage;
+    bool geoPassthroughEXT;
 #endif
 
     typedef std::list<TCall> TGraph;