Added some comments

source/app/src/App.cpp

@@ -16,10 +16,12 @@
 namespace ugly {
 
 int App::main(std::vector<std::string> &args) {
+    // Initialize global log.
     auto cerrLog = TimestampLog{"ugly::log", std::cerr};
     log = LogAlias{&cerrLog};
     log("hello, world! app started.");
 
+    // Initialize GLFW.
     glfwSetErrorCallback(error_callback_s);
     glfwInit();
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
@@ -27,6 +29,7 @@ int App::main(std::vector<std::string> &args) {
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
     glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
 
+    // Create GLFW window and OpenGL context for GLEW.
     auto window = glfwCreateWindow(640, 480, "uGLy", NULL, NULL);
     glfwMakeContextCurrent(window);
     glewExperimental = GL_TRUE;
@@ -34,9 +37,11 @@ int App::main(std::vector<std::string> &args) {
         log("glewInit() failed!");
     }
 
+    // Run app.
     auto app = App{window};
     app.game_loop();
 
+    // Clean up.
     glfwTerminate();
     glfwSetErrorCallback(NULL);
     log("app quitting.");
@@ -57,7 +62,8 @@ void App::key_callback_s(GLFWwindow *window, int key, int scancode, int action,
 
 
 App::App(GLFWwindow *window):
-    mpWindow{window} {
+    mpWindow{window},
+    mShaderProgram{} {
     glfwSetWindowUserPointer(mpWindow, this);
     glfwSetKeyCallback(mpWindow, key_callback_s);