Objectives

Review the approach to model load and rendering
Refactor the existing classes into an 5 primary domains:
- scene
- physics
- model
- world
- utils
Construct an application along these lines - illustrated by a forces applied to a cube

Setup

Create a new project in the usual way - called lab08b_model_with_physics - in the usual way.
Create the following folders in the src folderd:
scene
physics
model
utils
world
Incorporate the sources into these folders in the next three steps
For reference purposes only, you might like to download and expand this final version of the project for this lab:
lab08b_model.zip
However, it would be best if you explored the project as suggested in the lab steps.

Utils

Incorporate the following classes into utils:
color.h
color.cpp
vector3.h
vector3.cpp
libopengl.h
libs.h

Scene I

renderable.h

Model

World I

World classes

Incorporate these classes into the world folder:
glutadapter.h
glutadapter.cpp
projection.h
projection.cpp
projectors.h
projectors.cpp
world.h
world.cpp
The project should now build - however we still need a main for it to link:
main.cpp
If you put this model file on the default path:
testcube.obj
This is the original maya file:
model.mb
If you run the program, it should display:

Verify that the perspective switch keys (1-4) work as per last lab

Camera

Introduce the following classes into the world package:
camera.h
camera.cpp
Now incorporate a camera member into the world class:

struct World
{
  void initialize(std::string name, int width, int height);
  void keyPress(unsigned char ch);
  void start();
  void render();

  static World&amp; GetInstance();
  static World  *s_World;

  GeometryMap   *renderables;
  Projectors     projectors;
  Camera         camera;
};

In the render method of World, we incorporate the camera render:

void World::render()
{
  glClearColor(0.0, 0.0, 0.0, 1.0);
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  if (projectors.isPerspective())
  {
    glLoadIdentity();
    camera.render();
  }
  //...
}

Now adjust to keypress function to pass on keystrokes to the camera:

void World::keyPress(unsigned char ch)
{
  if (ch >= '1' &amp;&amp; ch <= '4')
  {
    projectors.keyPress(ch);
  }
  else
  {
    if (projectors.isPerspective())
    {
      camera.keyStroke(ch);
    }
  }
  glutPostRedisplay();
}

Run and test - the keys a,s,d,f,w,e,z,x,c should allow you to navigate through the scene.

Scene II

Introduce some more actor classes, in both the 'scene' and the 'physics' folders

Scene

Physics

Introduce these two classes into the physics folder: - cubeactor.h

cubeactor.cpp

These should build without incident

World II

World class

Change the World class so that it now holds a reference to a scene instead of a geomertymap:

  //GeometryMap   *renderables;
  Scene         *scene;

Also in World, introduce a new method:

  void tickAndRender();

In World implementation, we need to implement this function:

void World::tickAndRender()
{
  static clock_t lastTime = 0;

  if (lastTime == 0)
    lastTime = clock();

  clock_t currTime = clock();
  clock_t deltaTime = currTime - lastTime;
  float secondsDelta = (float)deltaTime/CLOCKS_PER_SEC;

  scene->tick(secondsDelta);

  glutPostRedisplay();
}

Also in World, change our current render to the following:

  //foreach (GeometryMap::value_type geometry, *renderables)
 // {
 //   geometry.second.render();
 // }
  scene->render();

Finally, we must start the timer:

void World::start()
{
  timerFunc(0);
  glutMainLoop();
}

Main

In main, before we start the world, we load the scene:

 // theWorld.renderables = &amp;model->entities;
  Scene *scene = new Scene (model);
  theWorld.scene = scene;
  theWorld.start();

In glutadapter.h, we need a new timer function:

void timerFunc(int value);

and in glutadapter.cpp, its implementation:

void timerFunc(int value)
{
  theWorld.tickAndRender();
  glutTimerFunc(50, timerFunc, 1);
}

Build and Test

If you are loading the same model, it contains a object called 'cube'. The above code had wires behaviour for that object
When you run the program, the cube should animate