Download Screen shot and Readme Applet MSDOS version .
VRML Viewpoints Applet
Robert Inventor's programs
Enter coords of viewpoint, and of point to look towards.
Then click Make Viewpoint.
You can tilt the view about the line from viewpoint to point looked at. The tilt is in degrees because that's easier for common angles like 45 degrees and 90 degrees. Example to show effect of tilt .
You can freely use and modify the Source code in your own programs if you wish.
Any email about it to VRML_viewpoints_applet@robertinventor.com
Stephen Chenney uses a different method using quaternions in his MSDOS program ORIENT
His program has an up vector instead of the tilt. Setting the up vector to 0 1 0 corresponds to a tilt of 0.
Other up vectors could correspond to varying tilts, depending on the direction of view - for instance an up vector of 1 0 0 requires a tilt of -90 degrees for a viewpoint from 0 0 1 to 0 0 0; 90 degrees for one from 0 0 -1 to 0 0 0; and 180 degrees for one from 1 x 0 to 0 0 0 (any value of x greater than 0).
You can find his program in this List of VRML utilities.
You can get back to this page using the short URLs:
go.to/v.v or go.to/vrmlviewpoints