Shaders - directives for uniforms

shaders.cc

@@ -6,7 +6,7 @@
 namespace {
 
 const std::regex PreprocDirective_( "^\\s*//!\\s*([a-z]+(\\s+([^\\s]+))*)\\s*$" );
-
+const std::regex UniformName_( "^[A-Za-z][A-Za-z0-9_]*$" );
 const std::regex GLSLErrorNv_( "^[0-9]*\\(([0-9]+).*$" );
 
 const std::map< std::string , E_ShaderInput > InputTypes_( ([] {
@@ -22,6 +22,20 @@ const std::map< std::string , E_ShaderInput > InputTypes_( ([] {
 	return t;
 })());
 
+const std::unordered_map< std::string , E_UniformType > UniformTypes_( ([] {
+	std::unordered_map< std::string , E_UniformType > t;
+	t.emplace( "float" , E_UniformType::F1 );
+	t.emplace( "vec2" , E_UniformType::F2 );
+	t.emplace( "vec3" , E_UniformType::F3 );
+	t.emplace( "vec4" , E_UniformType::F4 );
+	t.emplace( "int" , E_UniformType::I1 );
+	t.emplace( "ivec2" , E_UniformType::I2 );
+	t.emplace( "ivec3" , E_UniformType::I3 );
+	t.emplace( "ivec4" , E_UniformType::I4 );
+	t.emplace( "sampler2D" , E_UniformType::SAMPLER2D );
+	return t;
+})());
+
 const GLenum ProgramTypes_[] = {
 	GL_VERTEX_SHADER ,
 	GL_FRAGMENT_SHADER ,
@@ -64,11 +78,16 @@ struct T_InputReader_
 	~T_InputReader_( );
 
 	void read( );
+
+	void handleDirective(
+		__rd__ T_Tokens_ const& tokens );
+	void parseInputDirective(
+		__rd__ T_Tokens_ const& tokens );
+
+	void error(
+		__rd__ std::string const& err );
 	void nl( );
 	void addAccumulated( );
-	void handleDirective(
-			__rd__ T_Tokens_ const& tokens );
-	void error( __rd__ std::string const& err );
 };
 
 /*----------------------------------------------------------------------------*/
@@ -103,22 +122,7 @@ void T_InputReader_::read( )
 	addAccumulated( );
 }
 
-void T_InputReader_::nl( )
-{
-	accumLines ++;
-	accumulator += '\n';
-}
-
-void T_InputReader_::addAccumulated( )
-{
-	if ( accumLines ) {
-		auto& ck( input.chunks );
-		ck.emplace_back( E_ShaderInputChunk::CODE ,
-				std::move( accumulator ) , accumLines );
-		accumulator = {};
-		accumLines = 0;
-	}
-}
+/*----------------------------------------------------------------------------*/
 
 void T_InputReader_::handleDirective(
 		__rd__ T_Tokens_ const& tokens )
@@ -148,20 +152,89 @@ void T_InputReader_::handleDirective(
 			input.type = pos->second;
 		}
 
+	} else if ( directive == "input" ) {
+		nl( );
+		parseInputDirective( tokens );
+
+	} else if ( directive == "uniforms" ) {
+		nl( );
+		for ( auto const& c : input.chunks ) {
+			if ( c.type == E_ShaderInputChunk::UNIFORMS ) {
+				error( "duplicate uniform generation" );
+				return;
+			}
+		}
+		input.chunks.emplace_back( E_ShaderInputChunk::UNIFORMS , "" , 1 );
+
 	} else {
 		nl( );
 		error( "unknown directive" );
 	}
 }
 
+void T_InputReader_::parseInputDirective(
+	__rd__ T_Tokens_ const& tokens )
+{
+	if ( tokens.size( ) != 4 ) {
+		error( "invalid arguments" );
+		return;
+	}
+
+	// Local/global
+	const bool global{ tokens[ 1 ] == "global" };
+	if ( !global && tokens[ 1 ] != "local" ) {
+		error( "second argument should be 'local' or 'global'" );
+		return;
+	}
+
+	// Name
+	std::string const& name{ tokens[ 2 ] };
+	if ( input.uniforms.find( name ) != input.uniforms.end( ) ) {
+		error( "duplicate uniform" );
+		return;
+	}
+	if ( !std::regex_match( name , UniformName_ ) ) {
+		error( "invalid uniform name" );
+		return;
+	}
+
+	// Type
+	auto tPos( UniformTypes_.find( tokens[ 3 ] ) );
+	if ( tPos == UniformTypes_.end( ) ) {
+		error( "unsupported uniform type" );
+		return;
+	}
+
+	input.uniforms.emplace( tokens[ 2 ] , T_ShaderUniform{
+			tokens[ 2 ] , global , tPos->second } );
+}
+
+/*----------------------------------------------------------------------------*/
+
 void T_InputReader_::error(
 		__rd__ std::string const& err )
 {
-	printf( "input error (%d - %s)\n" , line , err.c_str( ) );
 	input.errors.push_back( T_ShaderInputError{
 			line , err } );
 }
 
+void T_InputReader_::nl( )
+{
+	accumLines ++;
+	accumulator += '\n';
+}
+
+void T_InputReader_::addAccumulated( )
+{
+	if ( accumLines ) {
+		auto& ck( input.chunks );
+		ck.emplace_back( E_ShaderInputChunk::CODE ,
+				std::move( accumulator ) , accumLines );
+		accumulator = {};
+		accumLines = 0;
+	}
+}
+
 } // namespace
 
 

shaders.hh

@@ -8,7 +8,8 @@
 // Type of input chunk
 enum class E_ShaderInputChunk {
 	CODE ,
-	INCLUDE
+	INCLUDE ,
+	UNIFORMS
 };
 
 // Input chunk data
@@ -44,12 +45,28 @@ struct T_ShaderInputError
 	std::string error;
 };
 
+// Uniform types
+enum class E_UniformType {
+	F1 , F2 , F3 , F4 ,
+	I1 , I2 , I3 , I4 ,
+	SAMPLER2D
+};
+
+// Uniform declarations
+struct T_ShaderUniform
+{
+	std::string name;
+	bool global;
+	E_UniformType type;
+};
+
 // Source file
 struct T_ShaderInput
 {
 	E_ShaderInput type = E_ShaderInput::CHUNK;
 	std::vector< T_ShaderInputChunk > chunks;
 	std::vector< T_ShaderInputError > errors;
+	std::unordered_map< std::string , T_ShaderUniform > uniforms;
 
 	bool load( __rd__ std::string const& path );
 };