X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fglsl%2Fgenerate.cpp;h=02021a4c39993c999f544c8718ea40292a4b0806;hb=b7702a7162bba41718dd56b875e5d911f5ab3edb;hp=90128a18e1a7bbdfcaa023579c9665cac27c9a78;hpb=858d937501ef794c29fd62921e74b90580ffc965;p=libs%2Fgl.git diff --git a/source/glsl/generate.cpp b/source/glsl/generate.cpp index 90128a18..02021a4c 100644 --- a/source/glsl/generate.cpp +++ b/source/glsl/generate.cpp @@ -139,6 +139,9 @@ void VariableResolver::visit(VariableReference &var) { var.declaration = 0; r_members = 0; + /* Look for variable declarations in the block hierarchy first. Interface + blocks are always defined in the top level so we can't accidentally skip + one. */ for(Block *block=current_block; (!var.declaration && block); block=block->parent) { map::iterator i = block->variables.find(var.name); @@ -157,6 +160,8 @@ void VariableResolver::visit(VariableReference &var) map::const_iterator i = blocks.find(var.name); if(i!=blocks.end() && i->second->instance_name==var.name) { + /* The name refers to an interface block with an instance name rather + than a variable. Prepare a new syntax tree node accordingly. */ r_iface_ref = new InterfaceBlockReference; r_iface_ref->name = var.name; r_iface_ref->declaration = i->second; @@ -164,6 +169,7 @@ void VariableResolver::visit(VariableReference &var) } else { + // Look for the variable in anonymous interface blocks. for(i=blocks.begin(); (!var.declaration && i!=blocks.end()); ++i) if(i->second->instance_name.empty()) { @@ -178,6 +184,8 @@ void VariableResolver::visit(VariableReference &var) { if(r_assignment_target) { + /* More than one variable reference found in assignment target. + Unable to determine what the primary target is. */ record_target = false; r_assignment_target = 0; } @@ -240,6 +248,8 @@ void VariableResolver::visit(BinaryExpression &binary) if(binary.oper->token[0]=='[') { { + /* The subscript expression is not a part of the primary assignment + target. */ SetFlag set(record_target, false); binary.right->visit(*this); } @@ -338,6 +348,7 @@ void FunctionResolver::visit(FunctionDeclaration &func) { stage_decl = &func; + // Set all previous declarations to use this definition. for(vector::iterator i=decls.begin(); i!=decls.end(); ++i) { (*i)->definition = func.definition; @@ -416,6 +427,8 @@ bool InterfaceGenerator::generate_interface(VariableDeclaration &var, const stri iface_var->interface = iface; iface_var->type = var.type; iface_var->name = name; + /* Geometry shader inputs are always arrays. But if we're bringing in an + entire block, the array is on the block and not individual variables. */ if(stage->type==Stage::GEOMETRY && !copy_block) iface_var->array = ((var.array && var.interface!="in") || iface=="in"); else @@ -491,7 +504,7 @@ void InterfaceGenerator::visit(VariableReference &var) { if(var.declaration || !stage->previous) return; - /* Don't pull a variable from previous stage if we just generated an out + /* Don't pull a variable from previous stage if we just generated an output interface in this stage */ if(stage->content.variables.count(var.name)) return; @@ -539,6 +552,7 @@ void InterfaceGenerator::visit(VariableDeclaration &var) { if(iface_block->linked_block) { + // Link all variables to their counterparts in the linked block. const map &linked_vars = iface_block->linked_block->members.variables; map::const_iterator i = linked_vars.find(var.name); if(i!=linked_vars.end()) @@ -549,8 +563,8 @@ void InterfaceGenerator::visit(VariableDeclaration &var) if(var.interface=="out") { - /* For out variables in function scope, generate a global interface and - replace the local declaration with an assignment. */ + /* For output variables in function scope, generate a global interface + and replace the local declaration with an assignment. */ if(function_scope && generate_interface(var, "out", var.name)) { nodes_to_remove.insert(&var); @@ -565,8 +579,8 @@ void InterfaceGenerator::visit(VariableDeclaration &var) } else if(var.interface=="in") { - /* Try to link in variables in global scope with out variables from - previous stage */ + /* Try to link input variables in global scope with output variables from + previous stage. */ if(current_block==&stage->content && !var.linked_declaration && stage->previous) { const map &prev_vars = stage->previous->content.variables; @@ -586,6 +600,8 @@ void InterfaceGenerator::visit(InterfaceBlock &iface) { if(iface.interface=="in") { + /* Try to link input blocks with output blocks sharing the same block + name from previous stage. */ if(!iface.linked_block && stage->previous) { const map &prev_blocks = stage->previous->interface_blocks; @@ -613,6 +629,7 @@ void InterfaceGenerator::visit(Passthrough &pass) { vector pass_vars; + // Pass through all input variables of this stage. for(map::const_iterator i=stage->content.variables.begin(); i!=stage->content.variables.end(); ++i) if(i->second->interface=="in") pass_vars.push_back(i->second); @@ -625,6 +642,8 @@ void InterfaceGenerator::visit(Passthrough &pass) if(i->second->interface!="out") continue; + /* Pass through output variables from the previous stage, but only + those which are not already linked to an input here. */ if(!i->second->linked_declaration && generate_interface(*i->second, "in", i->second->name)) pass_vars.push_back(i->second); } @@ -632,6 +651,8 @@ void InterfaceGenerator::visit(Passthrough &pass) if(stage->type==Stage::GEOMETRY) { + /* Special case for geometry shader: copy gl_Position from input to + output. */ InterfaceBlockReference *ref = new InterfaceBlockReference; ref->name = "gl_in";