game/src/main.cpp

// Include Config header generated by GNU autotools
#include <GL/glew.h>
// Make sure Glew is loaded first
#include <GL/gl.h>
#include <SDL2/SDL.h>
// File reader
#include <string>
// Shader
#include "ShaderLoader.h"
// Camera
#include "PlayerCamera.h"
#include "helpers/RootDir.h"
// Objects
#include "Mesh.h"
#include "Model.h"

// Include error class
#include "Error.h"
Error error("main");

int main(int argc, char **argv) {
  // Initialise SDL2
  if (SDL_Init(SDL_INIT_EVERYTHING) != 0) {
    error.crash("Unable to initialise SDL: ", SDL_GetError());
    return 1;
  }

  // Make OpenGL use double buffering (Render game first then shove to output)
  SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

  // Initialise depth buffer
  SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16);

  // TODO: Discover if this is necessary for linux and what values they need be
  // SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
  // SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
  // SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
  // SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);

  // Create Window
  SDL_Window *window =
      SDL_CreateWindow("Game", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
                       800, 600, SDL_WINDOW_SHOWN | SDL_WINDOW_OPENGL);
  if (window == NULL) {
    error.crash("Unable to initialise SDL Window: ", SDL_GetError());
    return 1;
  }

  // Create glContext
  SDL_GLContext glContext = SDL_GL_CreateContext(window);
  if (!glContext) {
    error.crash("No SDL OpenGL Context initialised.");
  }

  // Tell us the number of vertex attributes allowed in bug reports
  int nrAttributes;
  glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &nrAttributes);
  error.log("Maximum num of vertex attributes supported: " +
            std::to_string(nrAttributes));

  // Initialise Glew
  if (glewInit() != GLEW_OK) {
    error.crash("Unable to initialise GLEW (OpenGL Extention Wrangler)");
  }

  // Create event handling struct
  SDL_Event input;

  ShaderLoader shader(ROOT_DIR "data/shaders/pbrVertex.glsl",
                      ROOT_DIR "data/shaders/pbrFragment.glsl");

  // Model backpack(std::string(ROOT_DIR) +
  //             std::string("data/models/backpack/backpack.obj"));
  // Model cube(ROOT_DIR "data/models/cube/cube.obj");
  // Model gun(ROOT_DIR "data/models/gun/Cerberus_LP.FBX");
  Model boxbarrel(ROOT_DIR
                  "data/models/wooden_boxbarrel/wooden_box_and_barrel.obj");
  // cube.translate(glm::vec3(3.0f, 0.0f, -1.0f));
  // backpack.translate(glm::vec3(-3.0f, 0.0f, 0.0f));
  // gun.translate(glm::vec3(0.0f, 1.0f, 0.0f));
  // gun.resize(glm::vec3(0.02f, 0.02f, 0.02f));
  // gun.rotate(glm::radians(-90.0f), glm::vec3(0.0f, 1.0f, 0.0f));

  // Create player camera object
  PlayerCamera camera;

  // Enable Render order things don't render in front of the wrong objects
  glEnable(GL_DEPTH_TEST);
  glEnable(GL_CULL_FACE);
  // glCullFace(GL_FRONT);
  glClearColor(0.2f, 0.3f, 0.3f, 1.0f);

  // Game loop
  bool running = true;
  while (running) {
    // SDL Event handling loop
    while (SDL_PollEvent(&input) > 0) {
      // Handle SDL quit event
      if (input.type == SDL_QUIT) {
        running = false;
      }
      switch (input.type) {
      case SDL_QUIT:
        running = false;
      case SDL_KEYDOWN:
        const Uint8 *keys = SDL_GetKeyboardState(NULL);
        if (keys[SDL_SCANCODE_ESCAPE])
          running = false;
      }
    };

    // TODO: Run game here lol
    camera.tick();

    // Clear screen ready for next loop
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    // Make every shader/rendering call from this point on use our shader
    // glUseProgram(shaderProgram);

    // Send our glsl shader our camera information
    shader.setMat4("MVP", camera.getMVP());
    shader.setVec3("CameraPos", camera.getCameraPosition());
    shader.setInt("tick", SDL_GetTicks());

    // Draw Meshes
    // cube.draw(shader);
    // backpack.draw(shader);
    // gun.draw(shader);
    boxbarrel.draw(shader);
    // Finally render everything
    shader.use();

    SDL_GL_SwapWindow(window);
  };

  // Escaped Game loop

  // On close also destroy window
  SDL_DestroyWindow(window);

  // Close all leftover SDL systems
  SDL_Quit();

  return 0;
}