Controlling the Viewpoint

Motivation

  • By default, the viewer enters a world at (0.0, 0.0, 10.0)
  • You can provide your own preferred view points
    • Select the entry point position
    • Select favorite views for the viewer
    • Name the views for a browser menu

Creating viewpoints

  • Viewpoints specify a desired location, an orientation, and a camera field of view lens angle
  • Viewpoints can be transformed using a Transform node
  • The first viewpoint found in a file is the entry point

Syntax: Viewpoint

A Viewpoint node specifies a named viewing location:

  • position and orientation - viewing location
  • fieldOfView - camera lens angle
  • description - description for viewpoint menu

XML Encoding

<Viewpoint
    position='0.0 0.0 10.0'
    orientation='0.0 0.0 1.0 0.0'
    fieldOfView='0.785'
    description='Entry View'/>

Classic Encoding

Viewpoint {
  position  0.0 0.0 10.0
  orientation 0.0 0.0 1.0 0.0
  fieldOfView 0.785
  description "Entry View"
}

Summary

  • Specify favorite viewpoints in Viewpoint nodes
  • The first viewpoint in the file is the entry viewpoint