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Using Tools Provided the Virtual Reality Exporter

Article by Dr. ES Kramer

The Virtual Reality Exporter Exporter provides some special tools for managing your scene. These include the Polygon Counter, the Level of Detail Helper, and the Export dialog box. The Polygon Counter is an excellent little gadget that keeps count of the number of faces in the scene as a whole, as well as in the selected object or objects. You can set a budget for the number of faces in the scene or for each object; the counter displays a colored "thermometer" when you approach the limit or go over the top.

This utility is invaluable when modeling to export. You soon get a sense of how many faces should be in various objects, according to their relative importance in the scene, and the Polygon Counter helps keep you on target. Use it in conjunction with the Optimize modifier for a real-time graphic display of the optimization process; as you change the modifier values by using the spinners, the Polygon Counter changes also. The Level of Detail Helper The Level of Detail (LOD) is one of the Virtual Reality Helper objects you can place in your scene. It speeds up navigation in the view port by displaying different objects, depending on their distance from the viewer.

You can have the browser display a detailed version of a building, for example, when the viewer comes within 100 units. As soon as the viewer moves farther away, the browser can display a less detailed version of the same building with fewer faces. You do not have to use different versions of the same objects. By substituting completely different objects, you can do a kind of simple morphing. Settings in the export dialog the virtual exporter's export dialog box has a number of settings that affect file size. Always leave the primitives to primitives, which require less code in the virtual file.

If you never need to look at the Virtual Reality Exporter code generated by the Exporter, you can uncheck the Indentation parameter. Indentation makes that code easier to read. Unchecking this parameter reduced the 45KB file just mentioned to 38KB. The Digits of Precision option controls the accuracy with which dimensions are calculated.

Reducing the Digits of Precision option from the default 4 to 3 is probably acceptable unless you have an architectural model or some other scene in which measurements need to be precise. Decreasing this parameter reduced the size of the test file to just under 36KB. It is probably not worth reducing the value of the Sample Rate parameter for transform animation.

Doing so does not save you much in terms of file size, but it does rapidly start to make the animation play back less smoothly. You might want to experiment with the sample rates if you have coordinated interpolation animation in the scene. Reducing the value in this case can make a significant difference in file size.