src/shaders.h

   1 #pragma once
   2
   3 #include <GL/gl3w.h>
   4 #include <vector>
   5 #include <string>
   6 #include <map>
   7 #include <set>
   8 #include <experimental/filesystem>
   9
  10 namespace fs = std::experimental::filesystem;
  11
  12 class ShaderBundle {
  13 public:
  14     using ShaderHandle = GLuint;
  15     using ProgramHandle = GLuint;
  16     using ShaderType = GLenum;
  17
  18     struct ShaderId {
  19                 fs::path path;
  20         ShaderType type;
  21         bool operator<(const ShaderId& rhs) const {
  22             return std::tie(path, type) < std::tie(rhs.path, rhs.type);
  23         }
  24         bool operator==(const ShaderId& rhs) const {
  25             return std::tie(path, type) == std::tie(rhs.path, rhs.type);
  26         }
  27     };
  28
  29     struct Shader {
  30         ShaderHandle handle;
  31
  32         int32_t hash;
  33     };
  34
  35     struct Program {
  36         // public handle; 0 until the program has successfully linked
  37         ProgramHandle handle;
  38
  39         ProgramHandle internal_handle;
  40     };
  41
  42     ShaderBundle() = default;
  43     ~ShaderBundle();
  44
  45     std::map<ShaderId, Shader> shader_pool;
  46     std::map<std::vector<ShaderId>, Program> programs;
  47
  48     ProgramHandle* add_program(const std::vector<std::pair<fs::path, ShaderType>>& shaders);
  49
  50     ShaderBundle& recompile();
  51     ShaderBundle& link();
  52
  53     static std::string preprocess(fs::path path, std::string shader);
  54 };