Texturing; OBJ loader

shaders.hh

@@ -0,0 +1,205 @@
+#ifndef __OPENGLPLAYGROUND_SHADERS_HH__
+#define __OPENGLPLAYGROUND_SHADERS_HH__
+
+#include <string>
+#include <unordered_map>
+
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+
+#include "common.hh"
+
+class ShaderException : public GLException {
+public:
+  ShaderException(std::string const& msg) : GLException(glGetError()), _msg(msg) {
+  }
+
+  virtual ~ShaderException() {}
+
+  std::string const& getMsg() const {return _msg;}
+  
+  virtual std::string toString() const {
+    return "ShaderException: " + _msg;
+  }
+  
+private:
+  std::string _msg;
+};
+
+class Program;
+
+class Shader {
+public:
+  Shader() : _shaderID(0) {
+  }
+  
+  Shader(std::string const& program, GLenum type) {
+    _shaderID = glCreateShader(type);
+    const char* const arr[] = {program.c_str()};
+    glShaderSource(_shaderID, 1, arr, NULL);
+    glCompileShader(_shaderID);
+    
+    int state;
+    glGetShaderiv(_shaderID, GL_COMPILE_STATUS, &state);
+    
+    if (!state) {
+      int logLength;
+      glGetShaderiv(_shaderID, GL_INFO_LOG_LENGTH, &logLength);
+      
+      char *log = new char[logLength];
+      glGetShaderInfoLog(_shaderID, logLength, NULL, log);
+      std::string msg(log);
+      delete[] log;
+      
+      glDeleteShader(_shaderID);
+      
+      throw ShaderException(msg);
+    }
+  }
+
+  virtual ~Shader() {
+    glDeleteShader(_shaderID);
+  }
+
+protected:
+  unsigned getID() const {
+    return _shaderID;
+  }
+
+  friend class Program;
+ 
+  unsigned int _shaderID;
+};
+  
+
+class VertexShader : public Shader {
+public:
+  VertexShader(std::string const& program) : Shader(program, GL_VERTEX_SHADER) {
+  }
+
+  virtual ~VertexShader() {
+  }
+};
+
+class FragmentShader : public Shader {
+public:
+  FragmentShader(std::string const& program) : Shader(program, GL_FRAGMENT_SHADER) {
+  }
+
+  virtual ~FragmentShader() {
+  }
+};
+
+class GeometryShader : public Shader {
+public:
+  GeometryShader(std::string const& program) : Shader(program, GL_GEOMETRY_SHADER) {
+  }
+
+  virtual ~GeometryShader() {
+  }
+};
+
+class Program {
+public:
+  Program(VertexShader& vertex, FragmentShader& frag) : _geom(nullptr), _vertex(vertex), _frag(frag) {
+    _progID = glCreateProgram();
+    
+    glAttachShader(_progID, _vertex.getID());
+    glAttachShader(_progID, _frag.getID());
+
+    glLinkProgram(_progID);
+    
+    int state;
+    glGetProgramiv(_progID, GL_LINK_STATUS, &state);
+    
+    if (!state) {
+      int logLength;
+      glGetProgramiv(_progID, GL_INFO_LOG_LENGTH, &logLength);
+      
+      char *log = new char[logLength];
+      glGetProgramInfoLog(_progID, logLength, NULL, log);
+      std::string msg(log);
+      delete[] log;
+      
+      glDeleteProgram(_progID);
+      
+      throw ShaderException(msg);
+    }
+
+    glDetachShader(_progID, _vertex.getID());
+    glDetachShader(_progID, _frag.getID());
+  }
+
+  Program(GeometryShader& geom, VertexShader& vertex, FragmentShader& frag) : _geom(&geom), _vertex(vertex), _frag(frag) {
+    _progID = glCreateProgram();
+
+    glAttachShader(_progID, _geom->getID());
+    glAttachShader(_progID, _vertex.getID());
+    glAttachShader(_progID, _frag.getID());
+
+    glLinkProgram(_progID);
+    
+    int state;
+    glGetProgramiv(_progID, GL_LINK_STATUS, &state);
+    
+    if (!state) {
+      int logLength;
+      glGetProgramiv(_progID, GL_INFO_LOG_LENGTH, &logLength);
+      
+      char *log = new char[logLength];
+      glGetProgramInfoLog(_progID, logLength, NULL, log);
+      std::string msg(log);
+      delete[] log;
+      
+      glDeleteProgram(_progID);
+      
+      throw ShaderException(msg);
+    }
+
+    glDetachShader(_progID, _geom->getID());
+    glDetachShader(_progID, _vertex.getID());
+    glDetachShader(_progID, _frag.getID());
+  }
+  
+  ~Program() {
+    glDeleteProgram(_progID);
+  }
+
+  void use() const {
+    glUseProgram(_progID);
+  }
+
+  int getUniformLocation(std::string const& name) const {
+    auto search = _uniformLocCache.find(name);
+    if (search != _uniformLocCache.end())
+      return search->second;
+   
+    int ret = glGetUniformLocation(_progID, name.c_str());
+    if (ret == -1)
+      throw GLException(glGetError());
+    _uniformLocCache.emplace(name, ret);
+    return ret;
+  }
+
+  int getAttribLocation(std::string const& name) const {
+    auto search = _attribLocCache.find(name);
+    if (search != _attribLocCache.end())
+      return search->second;
+    
+    int ret = glGetAttribLocation(_progID, name.c_str());
+    if (ret == -1)
+      throw GLException(glGetError());
+    _attribLocCache.emplace(name, ret);
+    return ret;
+  }
+  
+private:
+  GeometryShader* _geom;
+  VertexShader& _vertex;
+  FragmentShader& _frag;
+  unsigned _progID;
+
+  mutable std::unordered_map<std::string, GLint> _uniformLocCache, _attribLocCache;
+};
+
+#endif