Handle depth range conversion in geometry and tessellation shaders

Clip coordinates are taken from the last stage to deal with vertex
positions, so always converting in the vertex shader is not appropriate.
A geometry shader needs the conversion before every EmitVertex call.

diff --git a/source/glsl/compiler.cpp b/source/glsl/compiler.cpp
index 97c234f79285f3c253e94d76dd36b937d13e55b4..a717a9278be25be85066603bab71c9fd52422d49 100644 (file)
--- a/source/glsl/compiler.cpp
+++ b/source/glsl/compiler.cpp
@@ -94,10 +94,7 @@ void Compiler::compile(Mode mode)
                        ConstantSpecializer().apply(s, spec_values);
        }
        if(mode==PROGRAM)
-       {
-               for(Stage &s: module->stages)
-                       DepthRangeConverter().apply(s, features);
-       }
+               DepthRangeConverter().apply(*module, features);
        for(auto i=module->stages.begin(); i!=module->stages.end(); )
        {
                OptimizeResult result = optimize(*i);

diff --git a/source/glsl/finalize.cpp b/source/glsl/finalize.cpp
index e4d61ad13d87719bab032874c744ca6a7e959b59..91d2e44c52560fd6ff5fde842e9ef1d3d9f29076 100644 (file)
--- a/source/glsl/finalize.cpp
+++ b/source/glsl/finalize.cpp
@@ -252,12 +252,13 @@ void LocationAllocator::visit(VariableDeclaration &var)
 }
 
 
-void DepthRangeConverter::apply(Stage &stage, const Features &features)
+void DepthRangeConverter::apply(Module &module, const Features &features)
 {
-       if(stage.type!=Stage::VERTEX || features.target_api==VULKAN)
+       if(features.target_api==VULKAN)
                return;
 
-       stage.content.visit(*this);
+       for(Stage *s=&module.stages.back(); (!r_position_z_assigned && s); s=s->previous)
+               s->content.visit(*this);
 }
 
 NodePtr<Statement> DepthRangeConverter::create_conversion_statement()
@@ -298,6 +299,20 @@ NodePtr<Statement> DepthRangeConverter::create_conversion_statement()
        return statement;
 }
 
+void DepthRangeConverter::visit(Block &block)
+{
+       for(auto i=block.body.begin(); i!=block.body.end(); ++i)
+       {
+               r_emitvertex = false;
+               (*i)->visit(*this);
+               if(r_emitvertex && !r_position_z_assigned)
+               {
+                       block.body.insert_nocopy(i, create_conversion_statement());
+                       r_position_z_assigned = true;
+               }
+       }
+}
+
 void DepthRangeConverter::visit(VariableReference &var)
 {
        const StructDeclaration *strct = dynamic_cast<const StructDeclaration *>(var.type);
@@ -309,6 +324,11 @@ void DepthRangeConverter::visit(MemberAccess &memacc)
        r_gl_pervertex = false;
        memacc.left->visit(*this);
        r_gl_position = (r_gl_pervertex && memacc.member=="gl_Position");
+       if(assignment_target && r_gl_position)
+       {
+               r_position_assigned = true;
+               r_position_z_assigned = false;
+       }
 }
 
 void DepthRangeConverter::visit(Swizzle &swiz)
@@ -328,13 +348,22 @@ void DepthRangeConverter::visit(Assignment &assign)
        assign.right->visit(*this);
 }
 
+void DepthRangeConverter::visit(FunctionCall &call)
+{
+       if(call.name=="EmitVertex")
+               r_emitvertex = true;
+}
+
 void DepthRangeConverter::visit(FunctionDeclaration &func)
 {
        r_position_z_assigned = false;
        TraversingVisitor::visit(func);
 
-       if(func.definition==&func && func.name=="main" && !r_position_z_assigned)
+       if(func.definition==&func && func.name=="main" && r_position_assigned && !r_position_z_assigned)
+       {
                func.body.body.push_back_nocopy(create_conversion_statement());
+               r_position_z_assigned = true;
+       }
 }
 
 

diff --git a/source/glsl/finalize.h b/source/glsl/finalize.h
index 510f3987010e9488071c1e0702bdcf647c360639..7b47e8ec5a24aa492218e32036f61f065a5d68e1 100644 (file)
--- a/source/glsl/finalize.h
+++ b/source/glsl/finalize.h
@@ -69,18 +69,22 @@ private:
        bool assignment_target = false;
        bool r_gl_pervertex = false;
        bool r_gl_position = false;
+       bool r_emitvertex = false;
+       bool r_position_assigned = false;
        bool r_position_z_assigned = false;
 
 public:
-       void apply(Stage &, const Features &);
+       void apply(Module &, const Features &);
 
 private:
        NodePtr<Statement> create_conversion_statement();
 
+       virtual void visit(Block &);
        virtual void visit(VariableReference &);
        virtual void visit(MemberAccess &);
        virtual void visit(Swizzle &);
        virtual void visit(Assignment &);
+       virtual void visit(FunctionCall &);
        virtual void visit(FunctionDeclaration &);
 };
 

diff --git a/source/glsl/syntax.h b/source/glsl/syntax.h
index ebe188e1f6afa932fe5fd697509c043cfeb5ef23..1aa56cb708a05da8e1be7d379b5603a6e4edbf51 100644 (file)
--- a/source/glsl/syntax.h
+++ b/source/glsl/syntax.h
@@ -99,6 +99,9 @@ public:
 
        void push_back_nocopy(const typename C::value_type &v)
        { C::push_back(0); C::back() = v; }
+
+       void insert_nocopy(typename C::iterator i, const typename C::value_type &v)
+       { i = C::insert(i, 0); *i = v; }
 };
 
 template<typename T>