source/programbuilder.h

   1 #ifndef MSP_GL_PROGRAMBUILDER_H_
   2 #define MSP_GL_PROGRAMBUILDER_H_
   3
   4 #include <map>
   5 #include <string>
   6 #include <vector>
   7 #include <msp/datafile/objectloader.h>
   8
   9 namespace Msp {
  10 namespace GL {
  11
  12 class Program;
  13
  14 class invalid_variable_definition: public std::invalid_argument
  15 {
  16 public:
  17         invalid_variable_definition(const std::string &w): std::invalid_argument(w) { }
  18         virtual ~invalid_variable_definition() throw() { }
  19 };
  20
  21 /**
  22 Generates shaders with common features.
  23 */
  24 class ProgramBuilder
  25 {
  26 public:
  27         /**
  28         Describes the features of a standard shader program.
  29         */
  30         struct StandardFeatures
  31         {
  32                 class Loader: public DataFile::ObjectLoader<StandardFeatures>
  33                 {
  34                 public:
  35                         Loader(StandardFeatures &);
  36                 };
  37
  38                 bool texture;
  39                 bool material;
  40                 bool lighting;
  41                 unsigned max_lights;
  42                 bool specular;
  43                 bool normalmap;
  44                 bool shadow;
  45                 bool reflection;
  46                 bool legacy;
  47                 std::string custom;
  48
  49                 StandardFeatures();
  50
  51                 std::string create_flags() const;
  52         };
  53
  54 private:
  55         enum VariableScope
  56         {
  57                 NO_SCOPE,
  58                 UNIFORM,
  59                 ATTRIBUTE,
  60                 VERTEX,
  61                 FRAGMENT
  62         };
  63
  64         enum InterfaceFlags
  65         {
  66                 NO_INTERFACE = 0,
  67                 INPUT = 1,
  68                 OUTPUT = 2,
  69                 PASSTHROUGH = INPUT|OUTPUT,
  70                 GOAL = 4
  71         };
  72
  73         struct VariableDefinition
  74         {
  75                 VariableScope scope;
  76                 const char *name;
  77                 const char *type;
  78                 const char *expression;
  79                 const char *flags;
  80         };
  81
  82         struct ShaderVariable
  83         {
  84                 std::string name;
  85                 const VariableDefinition *variable;
  86                 std::string resolved_name;
  87                 bool fuzzy_space;
  88                 std::string resolved_space;
  89                 bool array_sum;
  90                 std::string array_subscript;
  91                 unsigned array_size;
  92                 std::list<ShaderVariable *> referenced_vars;
  93                 std::list<ShaderVariable *> referenced_by;
  94                 bool inlined;
  95                 bool inline_parens;
  96                 bool in_loop;
  97
  98                 ShaderVariable(const std::string &);
  99
 100                 void resolve(const VariableDefinition &);
 101                 void resolve(ShaderVariable &);
 102                 void resolve_space(const std::string &);
 103                 void resolve_array(const StandardFeatures &, unsigned = 0);
 104                 void add_reference(ShaderVariable &);
 105                 void update_reference(ShaderVariable &, ShaderVariable &);
 106                 void check_inline(bool, bool);
 107                 bool is_referenced_from(VariableScope) const;
 108                 InterfaceFlags get_interface_flags(VariableScope) const;
 109                 std::string create_declaration(char = 0, bool = false) const;
 110                 std::string create_replacement(VariableScope, const char * = 0) const;
 111                 std::string create_expression(const char * = 0) const;
 112         };
 113
 114         enum MatchType
 115         {
 116                 NO_MATCH,
 117                 EXACT,
 118                 FUZZY,
 119                 ARRAY
 120         };
 121
 122         StandardFeatures features;
 123         std::list<VariableDefinition> custom_variables;
 124         std::string feature_flags;
 125         bool optimize;
 126
 127         static const VariableDefinition standard_variables[];
 128         static const char interfaces[];
 129
 130 public:
 131         ProgramBuilder(const StandardFeatures &);
 132
 133         void set_optimize(bool);
 134         Program *create_program() const;
 135         void add_shaders(Program &) const;
 136 private:
 137         std::string create_source(const std::list<ShaderVariable *> &, VariableScope) const;
 138         bool evaluate_flags(const char *) const;
 139         static MatchType name_match(const char *, const char *, const char ** = 0);
 140         static bool parse_identifier(const char *, unsigned &, unsigned &);
 141         static std::vector<std::string> extract_identifiers(const char *);
 142         static std::string replace_identifiers(const char *, const std::map<std::string, std::string> &);
 143 };
 144
 145 } // namespace GL
 146 } // namespace Msp
 147
 148 #endif