Lesson12: Traversing with Orbit Camera in the Solar System

Overview 

As discussed in the  previous article, we saw how Orbit Camera is implemented. 

Details

The purpose of  Lesson12 is to demonstrate using Orbit Camera.

System  class diagram

The scene class overrides camera with an instance of OrbitCamera. 

Implementation

Scene

The functionality is implemented in the Scene class derived from BaseScene class. 

It creates an instance of WFObjParser which parses the "Solar system" OBJ files and generates instances of  MeshInfo objects, MaterialInfo objects, TextureInfo Objects. 

Each MeshInfo is associated with a MaterialInfo and 1 TextureInfo Object along with Vertex data. Each MeshInfo  is represented by an instance of GenericObj instance.

The three methods Init, DrawScene and Cleanup are overridden as below:

The Init method creates an instance of OrbitCamera and populates 3D objects of the Solar system

The DrawScene method draws a string and image. 

The message handler for IDOK is called when Apply button is pressed after updates are made in the input dialog. It refreshes the display.

The message handler for IDCANCEL is called when in Cancel button is pressed the input dialog. It calls 

OnCloseWindow to destroy window.

Finally the WM_CLOSE  event is  handled in OnCloseWindow function and the window is destroyed and  application is shutdown when the window is closed or Escape key is pressed. 

Application

Scene class is hosted main.cpp. which creates the scene object and displays it. Message pump is added to process windows messages.

Output

The output looks as shown in the top.