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         tokenizer.expect("#");
  18
  19         string token = tokenizer.peek_token();
  20         if(token=="pragma")
  21                 preprocess_pragma();
  22         else if(token=="version")
  23                 preprocess_version();
  24         else if(token=="define" || token=="undef" || token=="if" || token=="ifdef" || token=="ifndef" || token=="else" ||
  25                 token=="elif" || token=="endif" || token=="error" || token=="extension" || token=="line")
  26                 throw invalid_shader_source(tokenizer.get_location(), "Unsupported preprocessor directive '%s'", token);
  27         else if(!token.empty())
  28                 throw parse_error(tokenizer.get_location(), token, "a preprocessor directive");
  29 }
  30
  31 void Preprocessor::preprocess_version()
  32 {
  33         tokenizer.expect("version");
  34         string token = tokenizer.parse_token();
  35         unsigned version = lexical_cast<unsigned>(token);
  36         signal_version.emit(Version(version/100, version%100));
  37
  38         token = tokenizer.parse_token();
  39         if(!token.empty())
  40                 throw parse_error(tokenizer.get_location(), token, "end of line");
  41 }
  42
  43 void Preprocessor::preprocess_pragma()
  44 {
  45         tokenizer.expect("pragma");
  46         string token = tokenizer.parse_token();
  47         if(token=="MSP")
  48                 preprocess_pragma_msp();
  49 }
  50
  51 void Preprocessor::preprocess_pragma_msp()
  52 {
  53         string token = tokenizer.peek_token();
  54         if(token=="stage")
  55                 preprocess_stage();
  56         else
  57                 throw invalid_shader_source(tokenizer.get_location(), "Unrecognized MSP pragma '%s'", token);
  58
  59         token = tokenizer.parse_token();
  60         if(!token.empty())
  61                 throw parse_error(tokenizer.get_location(), token, "end of line");
  62 }
  63
  64 void Preprocessor::preprocess_stage()
  65 {
  66         tokenizer.expect("stage");
  67         tokenizer.expect("(");
  68         string token = tokenizer.parse_token();
  69         StageType stage = SHARED;
  70         if(token=="vertex")
  71                 stage = VERTEX;
  72         else if(token=="geometry")
  73                 stage = GEOMETRY;
  74         else if(token=="fragment")
  75                 stage = FRAGMENT;
  76         else
  77                 throw parse_error(tokenizer.get_location(), token, "stage identifier");
  78         tokenizer.expect(")");
  79
  80         signal_stage_change.emit(stage);
  81 }
  82
  83 } // namespace SL
  84 } // namespace GL
  85 } // namespace Msp