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Q: How do I move the camera through my virutal world?

I want to be able to move around in my virtual world, and I need to know how to move the camera. Where is the API for moving the camera or a sample application that shows how to do this?

A: You do not move the camera, you move the virtual world.

The concept of moving the camera does not work in VR Juggler. In Virtual Reality projection type systems (i.e. CAVE systems) the world needs to be rotated around the user (i.e. rotating the whole terrain/scene model around the user's position, which is determined by a tracking system). This can be done as easily as adding a transformation on top of whatever scene you are flying through. In desktop simulations or video games, the user (camera) is rotated in the world. This applies true for Head-Mounted Displays as well.

The two kinds of navigation are called world-centric and user-centric. In world-centric/CAVE systems, there really is no need for a camera object because the user's eyes become the camera. The computers calculate the view frusta (one frustum per projector) based on the user’s position. This allows the user to view the geometry of the scene correctly while looking any where at anytime. In user-centric systems, there is usually only one view to look through, so the user must tell the computer where to look by moving the camera.

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