Assignment 3 Frequently Asked Questions

Assignment 3 Frequently Asked Questions (FAQ)

Q. How can I control the number of polygons in a cylinder?

A. You can't as far as I know. Don't worry about the fact that things are not tesselated as much as you might like. In regards to the low level of detail model, use boxes in place of cyliders since you know they have six polygons.

Q. How should I implement low/high level of detail?

A. Use an LOD node as demonstrated in the Tutuorial pages. You will need to establish at least two viewpoints in your scene. One that shows off the high level of detail, and another that shows the low level of detail. These viewpoints will be the appropriate distance from your object to make sure the right LOD is displayed.

Q. How can I hook up an interpolator to scaling?

A. See this example http://graphics.stanford.edu/~jedavis/248/Assignments/VRML_Tutorial/exposedProto.wrl

Q. How can I hook up an interpolator to a PROTO?

A. See this example http://graphics.stanford.edu/~jedavis/248/Assignments/VRML_Tutorial/exposedProto.wrl

Q. What is a primative, I have to include 10 of them?

A. Each Sphere, Box, or Cylinder (or other things) is a primative. If you have three spheres, two cylinders, and a box, that makes six primatives.

Q. The browser's error messages for bad VRML are not very helpful. Is there a better way?

http://www.trapezium.com/vorlon.html has an on-line VRML validator. Thanks to Chris Quartetti for this as well as the next tip.

Q. How can I get more information about errors from the browser? Display the console by pressing '\'. This is extremely informative, giving syntax errors and line numbers for VRML as well as embedded JavaScript.