Add some documentation to the GLSL compiler

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

diff --git a/source/glsl/generate.h b/source/glsl/generate.h
index 1867cc3e2a7d1a909ec3f59368216f6d69e17d23..b82bdca365bc02e7fd856c86f5011eb124517f92 100644 (file)
--- a/source/glsl/generate.h
+++ b/source/glsl/generate.h
@@ -11,32 +11,59 @@ namespace Msp {
 namespace GL {
 namespace SL {
 
+/** Combines multiple declarations of the same identifier into one. */
 class DeclarationCombiner: private TraversingVisitor
 {
 private:
-       bool toplevel;
        std::map<std::string, std::vector<FunctionDeclaration *> > functions;
        std::map<std::string, VariableDeclaration *> variables;
        std::set<Node *> nodes_to_remove;
 
 public:
-       DeclarationCombiner();
-
        void apply(Stage &);
 
 private:
        virtual void visit(Block &);
        virtual void visit(FunctionDeclaration &);
        virtual void visit(VariableDeclaration &);
-       using TraversingVisitor::visit;
 };
 
+/** Manipulates specialization constants.  If values are specified, turns
+specialization constants into normal constants.  Without values assigns
+automatic constant_ids to specialization constants. */
+class ConstantSpecializer: private TraversingVisitor
+{
+private:
+       const std::map<std::string, int> *values;
+
+public:
+       ConstantSpecializer();
+
+       void apply(Stage &, const std::map<std::string, int> *);
+
+private:
+       virtual void visit(VariableDeclaration &);
+};
+
+/** Forms links between nested blocks in the syntax tree. */
+class BlockHierarchyResolver: private TraversingVisitor
+{
+public:
+       void apply(Stage &s) { s.content.visit(*this); }
+
+private:
+       virtual void enter(Block &);
+};
+
+/** Resolves variable references.  Variable references which match the name
+of an interface block are turned into interface block references. */
 class VariableResolver: private TraversingVisitor
 {
 private:
-       std::vector<Block *> blocks;
-       StructDeclaration *type;
-       bool anonymous;
+       Stage *stage;
+       Block *builtins;
+       std::map<std::string, VariableDeclaration *> *members;
+       RefPtr<InterfaceBlockReference> iface_ref;
        std::string block_interface;
        bool record_target;
        VariableDeclaration *assignment_target;
@@ -48,41 +75,52 @@ public:
        void apply(Stage &);
 
 private:
-       virtual void visit(Block &);
+       Block *next_block(Block &);
+
+       virtual void enter(Block &);
        virtual void visit(VariableReference &);
+       virtual void visit(InterfaceBlockReference &);
        virtual void visit(MemberAccess &);
        virtual void visit(BinaryExpression &);
        virtual void visit(Assignment &);
        virtual void visit(StructDeclaration &);
        virtual void visit(VariableDeclaration &);
        virtual void visit(InterfaceBlock &);
-       virtual void visit(FunctionDeclaration &);
-       virtual void visit(Iteration &);
-       using TraversingVisitor::visit;
 };
 
+/** Resolves function declarations and calls. */
 class FunctionResolver: private TraversingVisitor
 {
 private:
+       Stage *stage;
        std::map<std::string, std::vector<FunctionDeclaration *> > functions;
 
 public:
-       void apply(Stage &s) { visit(s.content); }
+       void apply(Stage &);
 
 private:
        virtual void visit(FunctionCall &);
        virtual void visit(FunctionDeclaration &);
-       using TraversingVisitor::visit;
 };
 
+/** Materializes implicitly declared interfaces.
+
+Out variable declarations inside functions are moved to the global scope.
+
+Passthrough statements are processed, generating out variables to match in
+variables and copying values.
+
+Unresolved variables are looked up in the previous stage's out variables. */
 class InterfaceGenerator: private TraversingVisitor
 {
 private:
        Stage *stage;
        std::string in_prefix;
        std::string out_prefix;
-       unsigned scope_level;
-       Block *current_block;
+       bool function_scope;
+       InterfaceBlock *iface_block;
+       bool copy_block;
+       Block *iface_target_block;
        NodeList<Statement>::iterator iface_insert_point;
        NodeList<Statement>::iterator assignment_insert_point;
        std::set<Node *> nodes_to_remove;
@@ -97,13 +135,17 @@ private:
        std::string change_prefix(const std::string &, const std::string &) const;
        virtual void visit(Block &);
        bool generate_interface(VariableDeclaration &, const std::string &, const std::string &);
+       bool generate_interface(InterfaceBlock &);
        ExpressionStatement &insert_assignment(const std::string &, Expression *);
        virtual void visit(VariableReference &);
        virtual void visit(VariableDeclaration &);
+       virtual void visit(InterfaceBlock &);
+       virtual void visit(FunctionDeclaration &);
        virtual void visit(Passthrough &);
-       using TraversingVisitor::visit;
 };
 
+/** Reorders declarations to ensure that declarations always appear before
+references. */
 class DeclarationReorderer: private TraversingVisitor
 {
 private:
@@ -116,7 +158,6 @@ private:
                FUNCTION
        };
 
-       unsigned scope_level;
        DeclarationKind kind;
        std::set<Node *> ordered_funcs;
        std::set<Node *> needed_funcs;
@@ -124,7 +165,7 @@ private:
 public:
        DeclarationReorderer();
 
-       void apply(Stage &s) { visit(s.content); }
+       void apply(Stage &s) { s.content.visit(*this); }
 
 private:
        virtual void visit(Block &);
@@ -134,7 +175,6 @@ private:
        virtual void visit(VariableDeclaration &);
        virtual void visit(InterfaceBlock &) { kind = VARIABLE; }
        virtual void visit(FunctionDeclaration &);
-       using TraversingVisitor::visit;
 };
 
 } // namespace SL