source/glsl/preprocessor.cpp

   1 #include "glsl_error.h"
   2 #include "preprocessor.h"
   3 #include "tokenizer.h"
   4
   5 using namespace std;
   6
   7 namespace Msp {
   8 namespace GL {
   9 namespace SL {
  10
  11 Preprocessor::Preprocessor(Tokenizer &t):
  12         tokenizer(t)
  13 { }
  14
  15 void Preprocessor::preprocess()
  16 {
  17         string token = tokenizer.peek_token();
  18         if(token=="pragma")
  19                 preprocess_pragma();
  20         else if(token=="version")
  21                 preprocess_version();
  22         else if(token=="define" || token=="undef" || token=="if" || token=="ifdef" || token=="ifndef" || token=="else" ||
  23                 token=="elif" || token=="endif" || token=="error" || token=="extension" || token=="line")
  24                 throw invalid_shader_source(tokenizer.get_location(), "Unsupported preprocessor directive '%s'", token);
  25         else if(!token.empty())
  26                 throw parse_error(tokenizer.get_location(), token, "a preprocessor directive");
  27 }
  28
  29 void Preprocessor::preprocess_version()
  30 {
  31         tokenizer.expect("version");
  32         string token = tokenizer.parse_token();
  33         unsigned version = lexical_cast<unsigned>(token);
  34         signal_version.emit(Version(version/100, version%100));
  35
  36         token = tokenizer.parse_token();
  37         if(!token.empty())
  38                 throw parse_error(tokenizer.get_location(), token, "end of line");
  39 }
  40
  41 void Preprocessor::preprocess_pragma()
  42 {
  43         tokenizer.expect("pragma");
  44         string token = tokenizer.parse_token();
  45         if(token=="MSP")
  46                 preprocess_pragma_msp();
  47 }
  48
  49 void Preprocessor::preprocess_pragma_msp()
  50 {
  51         string token = tokenizer.peek_token();
  52         if(token=="stage")
  53                 preprocess_stage();
  54         else
  55                 throw invalid_shader_source(tokenizer.get_location(), "Unrecognized MSP pragma '%s'", token);
  56
  57         token = tokenizer.parse_token();
  58         if(!token.empty())
  59                 throw parse_error(tokenizer.get_location(), token, "end of line");
  60 }
  61
  62 void Preprocessor::preprocess_stage()
  63 {
  64         tokenizer.expect("stage");
  65         tokenizer.expect("(");
  66         string token = tokenizer.parse_token();
  67         StageType stage = SHARED;
  68         if(token=="vertex")
  69                 stage = VERTEX;
  70         else if(token=="geometry")
  71                 stage = GEOMETRY;
  72         else if(token=="fragment")
  73                 stage = FRAGMENT;
  74         else
  75                 throw parse_error(tokenizer.get_location(), token, "stage identifier");
  76         tokenizer.expect(")");
  77
  78         signal_stage_change.emit(stage);
  79 }
  80
  81 } // namespace SL
  82 } // namespace GL
  83 } // namespace Msp