LOD
What is it?
The LOD (Level of Detail) node allows for different levels of detail and complexity in an object which is directly related to the user's distance from the object. At closer distances, an object with greater detail is loaded. The purpose of the LOD node is to lower loading time with files by working with human eyesight. We can't see details well at further distances, so detail at that distance is unnecessary, and by eliminating unnecessary detail the file will be smaller and load quicker. For more details about this node, check out the VRML 2.0 Spec.


Create the scene and add Cameras

1) First create a scene with all the objects, materials and NavigationInfo in the greatest of detail. To the right, we have created a simple world for you to use as an example.

2) Next it is a good idea to add at least one 'Camera' which will be a 'Viewpoint' in the VRML file, but the file will still work without Viewpoints. NOTE: The more Viewpoints the better in VRML files. The different browsers have various navigation abilities and restraints, therefore the Viewpoints are the one consistent way the user can view the file.

3) To add a Camera, go to the Creation panel/press the 'Camera' button and Choose 'Target' as the Object Type.

4) With your mouse, drag the Camera in the 'Top' viewport and stretch it out.

5) To view what the Camera is seeing, go to the Perspective viewport and press 'c' on the keyboard. And there you are from the Cameras point of view.

6) The Camera is easy to adjust with the Move and Rotate buttons, so test them out.

7) Also it is good to name your Cameras. The Camera name is what the user sees in the VRML browser as the name of the Viewpoint. Otherwise it will default to Camera01, Camera02 etc. Which is pretty boring, if you have a great viewpoint to show off.

8) Viewpoints help tell a story in the VRML file, because you can lead the viewer to ideal viewing points of the model which they might not otherwise explore.


How to implement a LOD into a MAX file:

9) Decide how many levels of detail (LOD) you want for a particular object. There will be one more 'level' than specified Range (distance).

10) In this case create 2 modifed versions of the original object in the same location. The two other versions can either be the same model with less face counts (less detail) or an entirely different object that will appear in the same place, but at a further distance. With a different object you can create a type of morphing.

11) Then go to the 'Creation' panel and choose 'Helpers' Under 'Helpers' in the pull down choose 'VRML 1.0/2.0/VRBL' and then choose the Object Type LOD.

12) Then go to your scene and drag the mouse anywhere. You will see an icon that signals to you that you have placed the LOD node.

13) Next select the Pick Objects button and choose all of the geometry that will be part of the LOD sequence. Either select the objects with the mouse OR press the keyboard letter 'H'. The selected objects will appear in the 'Pick Objects' box. To turn off the 'Pick Objects' button, press it again.

14) Once the objects are picked, a default Distance of zero is given to them. Therefore you will need to change them. Highlight the object and the Distance in the scroll panel can be changed. Highlight each object and assign increasing distances. For example,
  • detailed_model 100 (loads first)
  • less_detailed_model 150
  • even_less_detailed_model 200
15) MAX automatically determines Range and Levels from this information. Levels are how many objects are involved in the LOD sequence. Range is the number of different distances not counting the initial range that loads with the file.

16) In the Icon Size box, you can designate a larger or smaller icon size for the LOD node---but this is only for the MAX file and has no bearing on the VRML file.

17) All possible information for the 'LOD' node has been entered now. If you need to go back, after leaving the Creation panel, and alter any of the parameters, then go to the 'Modify' panel and adjust.

18) Now you have successively implemented the LOD node into your file.

19) To check, go to the 'Selection' menu! NOTE: You can name your LOD in the same way as every other object in MAX in the 'Name' field.
How to Export MAX files to VRML:

20) Now Skinny on over to 'File' and choose 'Export'. The Exporter knows that you are referring to the file that is open and requests that you name your file.

21) So first choose '.wrl' filetype Then name your file, i.e. 'SuchAndSuch.wrl'

22) Suggestion: Because you might need to go back to the MAX file and adjust part of your world, it is a good idea to keep the filename between to two files the same.
dFORM
dFORM