Chapter 7.   Walking Around the Models

This chapter looks at how to populate a scene with 3D models, and 2D images 'pretending' to be 3D. It's also about how to make the scene's background more realistic. The ObjView3D application is shown in the screenshots on the right.

The key techniques developed in this chapter are:

• 3D Model Loading
  Java 3D has built-in support for loading 3D models converted using the Wavefront OBJ format. I develop a ModelLoader class that simplifies the process, and explain how the loaded model can then be translated, rotated, and/or scaled.
   
  
• 2D Ground Cover
  The scene is decorated with 2D images which rest on the floor (e.g. the trees in the first screenshot) and always stay oriented towards the viewer, giving the impression that they're 3D. This is a cheap alternative to employing real 3D models.
   
  
• Keyboard-based Movement
  I've been using the Java 3D OrbitBehavior class to change the camera's viewpoint up to now, but ObjView3D uses a KeyBehavior class instead. Key presses move the camera forwards, backwards, left or right, rotate it left or right, and make it float up or down. However, the camera is prevented from descending through the floor.
   
  
• A Better Background
  I look at three ways of creating a background that contains interesting detail, and looks different when viewed from different places in the scene. The approaches are:
  1. A textured-wrapped sphere (used in the first screenshot).
      
     
  2. A skybox (a Java 3D Box with textures pasted onto each face).
      
     
  3. A skybox covered with Terragen-generated textures (shown in the second screenshot). This version is built from quads, which gives the programmer more control over how it's positioned. Terragen is a freeware photorealistic landscape renderer.

Downloads

• The PDF file for the draft chapter (200 KB). Last updated: 25th September 2006.
  
• Zipped Source code (705 KB). Last updated: 25th September 2006.
  

• Up to the Pro Java 6 3D Game Development Index Page
• Back to Chapter 6. A Multitextured Landscape
• On to Chapter 8. Backgrounds and Overlays