Shader loader - recreate shader code

externals.hh

@@ -19,6 +19,7 @@
 #include <memory>
 #include <fstream>
 #include <map>
+#include <set>
 #include <regex>
 
 // ImGui

shaders.cc

@@ -37,6 +37,7 @@ namespace {
 		~T_InputReader_( );
 
 		void read( );
+		void nl( );
 		void addAccumulated( );
 		void handleDirective(
 				__rd__ T_Tokens_ const& tokens );
@@ -73,12 +74,18 @@ namespace {
 		addAccumulated( );
 	}
 
+	void T_InputReader_::nl( )
+	{
+		accumLines ++;
+		accumulator += '\n';
+	}
+
 	void T_InputReader_::addAccumulated( )
 	{
 		if ( accumLines ) {
 			auto& ck( input.chunks );
-			ck.emplace( ck.end( ) , E_ShaderInputChunk::CODE ,
-					accumulator , accumLines );
+			ck.emplace_back( E_ShaderInputChunk::CODE ,
+					std::move( accumulator ) , accumLines );
 			accumulator = {};
 			accumLines = 0;
 		}
@@ -91,13 +98,16 @@ namespace {
 
 		if ( directive == "include" ) {
 			if ( tokens.size( ) != 2 ) {
+				nl( );
 				error( "invalid arguments" );
 				return;
 			}
+			addAccumulated( );
 			auto& ck( input.chunks );
-			ck.emplace( ck.end( ) , E_ShaderInputChunk::INCLUDE , tokens[ 1 ] , 1 );
+			ck.emplace_back( E_ShaderInputChunk::INCLUDE , tokens[ 1 ] , 1 );
 
 		} else if ( directive == "type" ) {
+			nl( );
 			if ( tokens.size( ) != 2 ) {
 				error( "invalid arguments" );
 				return;
@@ -110,6 +120,7 @@ namespace {
 			}
 
 		} else {
+			nl( );
 			error( "unknown directive" );
 		}
 	}
@@ -124,6 +135,8 @@ namespace {
 } // namespace
 
 
+/*= T_ShaderInput ============================================================*/
+
 bool T_ShaderInput::load(
 		__rd__ std::string const& path )
 {
@@ -133,7 +146,6 @@ bool T_ShaderInput::load(
 
 	FILE* const file{ fopen( path.c_str( ) , "r" ) };
 	if ( !file ) {
-		errors.push_back( T_ShaderInputError{ 0 , "unable to open" } );
 		return false;
 	}
 
@@ -144,20 +156,142 @@ bool T_ShaderInput::load(
 }
 
 
-#if 0
+/*============================================================================*/
+
+bool T_ShaderCodeLoader::load(
+		__rd__ std::string const& name ,
+		__wr__ T_Frankenshader& code )
+{
+	code = T_Frankenshader{ };
+
+	T_ShaderInput const* const main( getInput( name ) );
+	if ( !main ) {
+		return false;
+	}
+	if ( main->type == E_ShaderInput::LIBRARY
+			|| main->type == E_ShaderInput::CHUNK ) {
+		code.errors.push_back( T_ShaderError{ name , 0 ,
+				"incorrect file type" } );
+	} else {
+		code.type = E_ShaderType( int( main->type ) - 2 );
+	}
+
+	struct T_StackEntry_ {
+		std::string name;
+		T_ShaderInput const* input;
+		uint32_t pos;
+	};
+	std::map< std::string , uint32_t > pos;
+	std::vector< T_StackEntry_ > stack;
+	std::set< std::string > libraries;
+	T_ShaderInput const* current( main );
+	uint32_t cpos{ 0 };
+	std::string cname( name );
+	pos[ cname ] = 1;
+
+	while ( cpos < current->chunks.size( ) ) {
+		auto& chunk( current->chunks[ cpos ] );
+		if ( chunk.type == E_ShaderInputChunk::CODE ) {
+			// Chunk of code; just append it.
+			code.sources.push_back( cname );
+			code.counts.push_back( chunk.lines );
+			code.starts.push_back( pos[ cname ] );
+			code.code += chunk.text;
+			pos[ cname ] += chunk.lines;
+		} else {
+			// Include. Make sure we're not recursing.
+			const auto prevPos( pos[ cname ] );
+			pos[ cname ] += chunk.lines;
+			auto& nname( chunk.text );
+			if ( cname == nname || 0 != count_if( stack.begin( ) , stack.end( ) ,
+						[nname] ( T_StackEntry_ const& e ) {
+							return nname == e.name;
+						} ) ) {
+				code.errors.push_back( T_ShaderError{ cname , prevPos ,
+						"recursive inclusion of '" + nname + "'" } );
+
+			} else if ( libraries.find( nname ) == libraries.end( ) ) {
+				// Load it unless it's a library that's already included
+				T_ShaderInput const* const isi( getInput( nname ) );
+				if ( isi && ( isi->type == E_ShaderInput::CHUNK
+							|| isi->type == E_ShaderInput::LIBRARY ) ) {
+					// Ok, let's do this
+					if ( libraries.find( nname ) == libraries.end( ) ) {
+						for ( auto const& errs : isi->errors ) {
+							code.errors.push_back( T_ShaderError{
+									nname , errs.line , errs.error } );
+						}
+					}
+					libraries.insert( nname );
+					stack.push_back( T_StackEntry_{
+							cname , current , cpos } );
+					cname = nname;
+					current = isi;
+					cpos = UINT32_MAX;
+					pos[ cname ] = 1;
+
+				} else if ( isi ) {
+					// Trying to load a top-level shader
+					code.errors.push_back( T_ShaderError{ cname , prevPos ,
+							"trying to include a top-level file" } );
+				} else {
+					// Not found
+					code.errors.push_back( T_ShaderError{ cname , prevPos ,
+							"file not found" } );
+				}
+			}
+		}
+
+		cpos ++;
+		while ( cpos == current->chunks.size( ) && !stack.empty( ) ) {
+			T_StackEntry_ const& se( stack[ stack.size( ) - 1 ] );
+			pos.erase( cname );
+			cpos = se.pos + 1;
+			current = se.input;
+			cname = se.name;
+			stack.pop_back( );
+		}
+	}
+
+	return true;
+}
+
+T_ShaderInput const* T_ShaderCodeLoader::getInput(
+		__rd__ std::string const& name )
+{
+	auto pos( files.find( name ) );
+	if ( pos != files.end( ) ) {
+		return pos->second.get( );
+	}
+	T_ShaderInput ni;
+	if ( !ni.load( "shaders/" + name ) ) {
+		return nullptr;
+	}
+	files.emplace( name , std::make_unique< T_ShaderInput >(
+				std::move( ni ) ) );
+	return files.find( name )->second.get( );
+}
+
+void T_ShaderCodeLoader::removeInput(
+		__rd__ std::string const& name )
+{
+	files.erase( name );
+}
+
+
+#if 1
 void testLoadShaderFile( )
 {
 	const std::string source( "test-loader.glsl" );
-	const std::string sPath( "shaders/" + source );
-
-	T_ShaderInput input;
-	const bool ok( input.load( sPath ) );
-	printf( "OK? %s\n" , ok ? "yes" : "no" );
-	printf( "type: %d\n" , int( input.type ) );
-	printf( "chunks: %zu\n" , input.chunks.size( ) );
-	printf( "errors: %zu\n" , input.errors.size( ) );
-	for ( auto const& error : input.errors ) {
-		printf( "\tl%d: %s\n" , error.line , error.error.c_str( ) );
+	T_ShaderCodeLoader loader;
+	T_Frankenshader code;
+	if ( loader.load( source , code ) ) {
+		printf( "SUCCESS! TYPE = %d\n" , int( code.type ) );
+		for ( auto const& err : code.errors ) {
+			printf( "%s:%d: %s\n" , err.source.c_str( ) , err.line , err.error.c_str( ) );
+		}
+	} else {
+		printf( "fail :'(\n" );
 	}
 }
 #endif

shaders.hh

@@ -51,6 +51,49 @@ struct T_ShaderInput
 
 	bool load( __rd__ std::string const& path );
 };
+using P_ShaderInput = std::unique_ptr< T_ShaderInput >;
 
 
-//void testLoadShaderFile( );
+// Type of shader
+enum class E_ShaderType {
+	VERTEX , FRAGMENT ,
+};
+
+
+// Errors in shader code - the errors it represents may come from either
+// the input loader, the shader loader or the driver.
+struct T_ShaderError
+{
+	std::string source;
+	uint32_t line;
+	std::string error;
+};
+
+// Shader code after reconstitution
+// XXX rename this
+struct T_Frankenshader
+{
+	E_ShaderType type;
+	std::vector< uint32_t > starts;		// Position of chunk in source file
+	std::vector< uint32_t > counts;		// Chunk lengths
+	std::vector< std::string > sources;	// Chunk source files
+	std::string code;
+	std::vector< T_ShaderError > errors;
+};
+using P_Frankenshader = std::unique_ptr< T_Frankenshader >;
+
+// XXX test for the loader
+struct T_ShaderCodeLoader
+{
+	bool load( __rd__ std::string const& name ,
+			__wr__ T_Frankenshader& code );
+
+	T_ShaderInput const* getInput( __rd__ std::string const& name );
+	void removeInput( __rd__ std::string const& name );
+
+    private:
+	std::map< std::string , P_ShaderInput > files;
+};
+
+
+void testLoadShaderFile( );