Implement tessellation shaders in the shader compiler

[libs/gl.git] / source / glsl / generate.cpp

diff --git a/source/glsl/generate.cpp b/source/glsl/generate.cpp
index e4830ec22aee2340aae79a93711600f415ef89a6..cc427d05c30c3f9d66a32556d4ee2c5aa8d042d5 100644 (file)
--- a/source/glsl/generate.cpp
+++ b/source/glsl/generate.cpp
@@ -108,8 +108,15 @@ VariableDeclaration *InterfaceGenerator::generate_interface(VariableDeclaration
        iface_var->interface = iface;
        iface_var->type = var.type;
        iface_var->name = name;
-       // Geometry shader inputs are always arrays.
-       if(stage->type==Stage::GEOMETRY)
+       // Tessellation and geometry inputs may be arrayed.
+       if(stage->type==Stage::TESS_CONTROL)
+               // VS out -> TCS in: add | TCS in -> TCS out: unchanged | VS out -> TCS out: add
+               iface_var->array = (var.array || var.interface!="in");
+       else if(stage->type==Stage::TESS_EVAL)
+               // TCS out -> TES in: unchanged | TES in -> TES out: remove | TCS out -> TES out: remove
+               iface_var->array = (var.array && iface=="in");
+       else if(stage->type==Stage::GEOMETRY)
+               // VS/TES out -> GS in: add | GS in -> GS out: remove | VS/TES out -> GS out: unchanged
                iface_var->array = ((var.array && var.interface!="in") || iface=="in");
        else
                iface_var->array = var.array;
@@ -339,6 +346,38 @@ void InterfaceGenerator::visit(Passthrough &pass)
 }
 
 
+void LayoutDefaulter::apply(Stage &stage)
+{
+       if(stage.type==Stage::TESS_EVAL)
+       {
+               stage.content.visit(*this);
+               if((need_winding || need_spacing) && in_iface)
+               {
+                       if(need_winding)
+                               in_iface->layout.qualifiers.emplace_back("ccw");
+                       if(need_spacing)
+                               in_iface->layout.qualifiers.emplace_back("equal_spacing");
+               }
+       }
+}
+
+void LayoutDefaulter::visit(InterfaceLayout &iface)
+{
+       if(iface.interface=="in")
+       {
+               if(!in_iface)
+                       in_iface = &iface;
+               for(const Layout::Qualifier &q: iface.layout.qualifiers)
+               {
+                       if(q.name=="cw" || q.name=="ccw")
+                               need_winding = false;
+                       else if(q.name=="equal_spacing" || q.name=="fractional_even_spacing" || q.name=="fractional_odd_spacing")
+                               need_spacing = false;
+               }
+       }
+}
+
+
 void ArraySizer::apply(Stage &stage)
 {
        stage.content.visit(*this);