Viewpoint Node

The Viewpoint node specifies the user's location and viewing model parameters. This is a bindable node. 

The following fields are present: 

  • fieldOfView specifies an angle in radians. Small angles correspond to telephoto lenses, whereas large angles (up to 3.14) are the equivalent of wide-angle lenses. Note that perspective gets distorted with large values.
  • position specifies the user position in the coordinate system which the Viewpoint is defined.
  • orientation determines the direction at which the user is looking, it specifies a rotation relative to the default orientation which points along the Z axis in the negative direction.
  • description provides a textual description of the ViewPoint. Most browsers have a list of the Viewpoints found in their menus, the contents of that list is taken from the description fields of the ViewPoints. Also you can direct the browser to go to a Viewpoint by specifying the Viewpoint name after the URL, as in "my_world.wrl#my_viewpoint, where my_viewpoint is the value for the field description for a Viewpoint in the file my_world.wrl.
  • jump determines the Viewpoint transition when you change from the active Viewpoint to a new Viewpoint. If jump is TRUE then the user should be moved along the path from the current Viewpoint to the new Viewpoint, otherwise if jump is FALSE then the Viewpoint is simply changed without affecting the user's position.



  • In addition to the events common to all bindable nodes, this node generates the event bindTime with the current time when it receives the event set_bind

    Syntax:

    ViewPoint { 
    fieldOfView 0.785398
    position 0 0 10
    orientation 0 0 1 0
    description ""
    jump TRUE




    In the right example there are two Viewpoint defined, v1 and v2. The fields in the form relate to Viewpoint v1. You can move between the Viewpoints to see the effect of the jump field. In v2 jump is TRUE. v2 is placed at 0 -10 0 and looking at the origin.