Commit of work up to day 11 of learnopengl.com.

09-basic-light-materials/src/shader.cpp

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+#include "shader.hpp"
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <print>
+#include <filesystem>
+#include "dbc.hpp"
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
+
+namespace fs = std::filesystem;
+
+inline std::string read_file(const std::string& filename) {
+  // load the file
+  std::ifstream in_file{filename, std::ios::binary};
+
+  // get the size of the file
+  std::stringstream in_str;
+  in_str << in_file.rdbuf();
+  return in_str.str();
+}
+
+void check_error(const std::string& what, unsigned int thing, GLenum check_type) {
+  int success = 0;
+  char infoLog[512] = {0};
+
+  if(check_type == GL_LINK_STATUS) {
+    glGetProgramiv(thing, check_type, &success);
+
+    if(!success) {
+      glGetProgramInfoLog(thing, 512, NULL, infoLog);
+      dbc::sentinel(std::format("ERROR: Program {} compile failed: {}", what, infoLog));
+    }
+  } else {
+    glGetShaderiv(thing, check_type, &success);
+
+    if(!success) {
+      glGetShaderInfoLog(thing, 512, NULL, infoLog);
+      dbc::sentinel(std::format("ERROR: Shader {} compile failed: {}", what, infoLog));
+    }
+  }
+}
+
+unsigned int Shader::load_shader(const std::string& filename, GLenum shader_type) {
+  dbc::check(fs::exists(filename),
+      std::format("shader file {} does not exist", filename));
+
+  // create the shader
+  std::string shader_code = read_file(filename);
+  const char* shader_code_ptr = shader_code.c_str();
+
+  int shader_id = glCreateShader(shader_type);
+  glShaderSource(shader_id, 1, &shader_code_ptr, NULL);
+  glCompileShader(shader_id);
+
+  check_error(filename, shader_id, GL_COMPILE_STATUS);
+
+  // check compile error
+  return shader_id;
+}
+
+Shader::Shader(const char* vertexPath, const char* fragmentPath) {
+  unsigned int vertex = load_shader(vertexPath, GL_VERTEX_SHADER);
+  unsigned int fragment = load_shader(fragmentPath, GL_FRAGMENT_SHADER);
+
+  ID = glCreateProgram();
+  glAttachShader(ID, vertex);
+  glAttachShader(ID, fragment);
+  glLinkProgram(ID);
+
+  check_error("link", ID, GL_LINK_STATUS);
+
+  glDeleteShader(vertex);
+  glDeleteShader(fragment);
+}
+
+void Shader::use() const {
+  glUseProgram(ID);
+}
+
+void Shader::cleanup() {
+  glDeleteProgram(ID);
+}
+
+void Shader::setBool(const std::string &name, bool value) const {
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform1i(uniform, (int)value);
+}
+
+void Shader::setInt(const std::string &name, int value) const {
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform1i(uniform, value);
+}
+
+void Shader::setFloat(const std::string &name, float value) const {
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform1f(uniform, value);
+}
+
+void Shader::setVec4(const std::string &name, float v1, float v2, float v3, float v4) const {
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform4f(uniform, v1, v2, v3, v4);
+}
+
+void Shader::setVec4(const std::string &name, const glm::vec4& value) const
+{
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform4fv(uniform, 1, &value[0]);
+}
+
+void Shader::setVec3(const std::string &name, const glm::vec3& value) const
+{
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform3fv(uniform, 1, &value[0]);
+}
+
+void Shader::setVec3(const std::string &name, float v1, float v2, float v3) const {
+  auto uniform = glGetUniformLocation(ID, name.c_str());
+  glUniform3f(uniform, v1, v2, v3);
+}
+
+void Shader::setMat4(const std::string &name, const glm::mat4& mat) const {
+  unsigned int loc = glGetUniformLocation(ID, name.c_str());
+  glUniformMatrix4fv(loc, 1, GL_FALSE, glm::value_ptr(mat));
+}