This node is another one of the six grouping Nodes. LOD is used to allow the worlds you build to change from one representation of an object to another automatically. The child nodes specified in this node usually represent the same object or objects at varying levels of detail, from highest detail to lowest. But this is not always the case.
FILE FORMAT/DEFAULTS
LOD {
range [ ] # MFFloat
center 0 0 0 # SFVec3f}
The LOD's center, as defined in the format syntax above is changed by the current transformation of your VRML world. The distance from this newly transformed center to the view point is calculated. If this distance is less than the first value in the ranges array, then the first child of the LOD group is drawn. If the distance is between the first and second values in the ranges array, the second child is drawn. This continues as long as there are ranges in the ranges array and there are children to be drawn. There is an important consideration to keep in mind when using this technique. If you have placed N values in your ranges array, your LOD group should have N+1 children. If you specify too few children, the last child will be used repeatedly for the lowest levels of detail. On the other hand, if you specify too many children, these extra children will be ignored. Each value in the ranges array should be less than the previous value. If they aren't, the results of this technique will be undefined.
Example Use
The following code fragment is from I_tower.wrl.
LOD {
range [8, 14, 22, 34]
Separator {
MaterialBinding {
value OVERALL}
Material { ...
}
}
}