initial commit for coom in opengl

shader.hpp

@@ -0,0 +1,152 @@
+#ifndef SHADER_H
+#define SHADER_H
+
+#include "glm/glm.hpp"
+#include <glad/glad.h>
+
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <string>
+
+class Shader {
+public:
+  unsigned int ID;
+  // constructor generates the shader on the fly
+  // ------------------------------------------------------------------------
+  Shader(const char *vertexPath, const char *fragmentPath) {
+    // 1. retrieve the vertex/fragment source code from filePath
+    std::string vertexCode;
+    std::string fragmentCode;
+    std::ifstream vShaderFile;
+    std::ifstream fShaderFile;
+    // ensure ifstream objects can throw exceptions:
+    vShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
+    fShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
+    try {
+      // open files
+      vShaderFile.open(vertexPath);
+      fShaderFile.open(fragmentPath);
+      std::stringstream vShaderStream, fShaderStream;
+      // read file's buffer contents into streams
+      vShaderStream << vShaderFile.rdbuf();
+      fShaderStream << fShaderFile.rdbuf();
+      // close file handlers
+      vShaderFile.close();
+      fShaderFile.close();
+      // convert stream into string
+      vertexCode = vShaderStream.str();
+      fragmentCode = fShaderStream.str();
+    } catch (std::ifstream::failure &e) {
+      std::cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ: " << e.what()
+                << std::endl;
+    }
+    const char *vShaderCode = vertexCode.c_str();
+    const char *fShaderCode = fragmentCode.c_str();
+    // 2. compile shaders
+    unsigned int vertex, fragment;
+    // vertex shader
+    vertex = glCreateShader(GL_VERTEX_SHADER);
+    glShaderSource(vertex, 1, &vShaderCode, NULL);
+    glCompileShader(vertex);
+    checkCompileErrors(vertex, "VERTEX");
+    // fragment Shader
+    fragment = glCreateShader(GL_FRAGMENT_SHADER);
+    glShaderSource(fragment, 1, &fShaderCode, NULL);
+    glCompileShader(fragment);
+    checkCompileErrors(fragment, "FRAGMENT");
+    // shader Program
+    ID = glCreateProgram();
+    glAttachShader(ID, vertex);
+    glAttachShader(ID, fragment);
+    glLinkProgram(ID);
+    checkCompileErrors(ID, "PROGRAM");
+    // delete the shaders as they're linked into our program now and no longer
+    // necessary
+    glDeleteShader(vertex);
+    glDeleteShader(fragment);
+  }
+  // activate the shader
+  // ------------------------------------------------------------------------
+  void use() { glUseProgram(ID); }
+  // utility uniform functions
+  // ------------------------------------------------------------------------
+  void setBool(const std::string &name, bool value) const {
+    glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)value);
+  }
+  // ------------------------------------------------------------------------
+  void setInt(const std::string &name, int value) const {
+    glUniform1i(glGetUniformLocation(ID, name.c_str()), value);
+  }
+  // ------------------------------------------------------------------------
+  void setFloat(const std::string &name, float value) const {
+    glUniform1f(glGetUniformLocation(ID, name.c_str()), value);
+  }
+  // ------------------------------------------------------------------------
+  void setVec2(const std::string &name, const glm::vec2 &value) const {
+    glUniform2fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]);
+  }
+  void setVec2(const std::string &name, float x, float y) const {
+    glUniform2f(glGetUniformLocation(ID, name.c_str()), x, y);
+  }
+  // ------------------------------------------------------------------------
+  void setVec3(const std::string &name, const glm::vec3 &value) const {
+    glUniform3fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]);
+  }
+  void setVec3(const std::string &name, float x, float y, float z) const {
+    glUniform3f(glGetUniformLocation(ID, name.c_str()), x, y, z);
+  }
+  // ------------------------------------------------------------------------
+  void setVec4(const std::string &name, const glm::vec4 &value) const {
+    glUniform4fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]);
+  }
+  void setVec4(const std::string &name, float x, float y, float z,
+               float w) const {
+    glUniform4f(glGetUniformLocation(ID, name.c_str()), x, y, z, w);
+  }
+  // ------------------------------------------------------------------------
+  void setMat2(const std::string &name, const glm::mat2 &mat) const {
+    glUniformMatrix2fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE,
+                       &mat[0][0]);
+  }
+  // ------------------------------------------------------------------------
+  void setMat3(const std::string &name, const glm::mat3 &mat) const {
+    glUniformMatrix3fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE,
+                       &mat[0][0]);
+  }
+  // ------------------------------------------------------------------------
+  void setMat4(const std::string &name, const glm::mat4 &mat) const {
+    glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE,
+                       &mat[0][0]);
+  }
+
+private:
+  // utility function for checking shader compilation/linking errors.
+  // ------------------------------------------------------------------------
+  void checkCompileErrors(unsigned int shader, std::string type) {
+    int success;
+    char infoLog[1024];
+    if (type != "PROGRAM") {
+      glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
+      if (!success) {
+        glGetShaderInfoLog(shader, 1024, NULL, infoLog);
+        std::cout
+            << "ERROR::SHADER_COMPILATION_ERROR of type: " << type << "\n"
+            << infoLog
+            << "\n -- --------------------------------------------------- -- "
+            << std::endl;
+      }
+    } else {
+      glGetProgramiv(shader, GL_LINK_STATUS, &success);
+      if (!success) {
+        glGetProgramInfoLog(shader, 1024, NULL, infoLog);
+        std::cout
+            << "ERROR::PROGRAM_LINKING_ERROR of type: " << type << "\n"
+            << infoLog
+            << "\n -- --------------------------------------------------- -- "
+            << std::endl;
+      }
+    }
+  }
+};
+#endif