Support specialization constants in the GLSL compiler

[libs/gl.git] / tools / glslcompiler.cpp

diff --git a/tools/glslcompiler.cpp b/tools/glslcompiler.cpp
index 74b37ef6b20a2fb5a46e0d19142c460fed346c98..0ce5f01d722ac424c064d7a7f64d862f72b16390 100644 (file)
--- a/tools/glslcompiler.cpp
+++ b/tools/glslcompiler.cpp
@@ -2,11 +2,13 @@
 #include <msp/core/getopt.h>
 #include <msp/gl/glsl/compiler.h>
 #include <msp/io/print.h>
+#include <msp/strings/utils.h>
 
 class GlslCompiler: public Msp::RegisteredApplication<GlslCompiler>
 {
 private:
        std::string source_fn;
+       std::map<std::string, int> spec_values;
        bool parse_only;
        bool combined;
        Msp::GL::SL::Stage::Type stage;
@@ -28,11 +30,13 @@ GlslCompiler::GlslCompiler(int argc, char **argv):
        dump_ast(false)
 {
        string stage_str;
+       vector<string> spec_values_in;
 
        GetOpt getopt;
        getopt.add_option('c', "combined", combined, GetOpt::NO_ARG).set_help("Output combined GLSL");
        getopt.add_option('a', "dump-ast", dump_ast, GetOpt::NO_ARG).set_help("Dump AST for debugging");
        getopt.add_option('p', "parse_only", parse_only, GetOpt::NO_ARG).set_help("Only parse the loaded source, don't compile");
+       getopt.add_option('e', "specialize", spec_values_in, GetOpt::REQUIRED_ARG).set_help("Set specialization constant", "NAME:VALUE");
        getopt.add_option('s', "stage", stage_str, GetOpt::REQUIRED_ARG).set_help("Output GLSL for STAGE", "STAGE");
        getopt.add_argument("source", source_fn, GetOpt::REQUIRED_ARG).set_help("GLSL file to compile");
        getopt(argc, argv);
@@ -45,6 +49,21 @@ GlslCompiler::GlslCompiler(int argc, char **argv):
                stage = GL::SL::Stage::FRAGMENT;
        else if(!dump_ast)
                combined = true;
+
+       for(vector<string>::const_iterator i=spec_values_in.begin(); i!=spec_values_in.end(); ++i)
+       {
+               unsigned colon = i->find(':');
+               if(colon==string::npos || colon==0 || colon+1>=i->size())
+                       throw usage_error("Invalid specialization value");
+
+               string value_str = i->substr(colon+1);
+               int value;
+               if(isnumrc(value_str))
+                       value = lexical_cast<int>(value_str);
+               else
+                       value = lexical_cast<bool>(value_str);
+               spec_values[i->substr(0, colon)] = value;
+       }
 }
 
 int GlslCompiler::main()
@@ -52,6 +71,7 @@ int GlslCompiler::main()
        GL::SL::Compiler compiler(GL::SL::Features::all());
        IO::File file(source_fn);
        compiler.load_source(file, source_fn);
+       compiler.specialize(spec_values);
        if(!parse_only)
                compiler.compile(GL::SL::Compiler::PROGRAM);