[Date Index] [Thread Index] [Author Index]

How does one get the current values for ViewPoint et al?

• To: mathgroup at smc.vnet.net
• Subject: [mg114204] How does one get the current values for ViewPoint et al?
• From: Joseph Gwinn <joegwinn at comcast.net>
• Date: Sat, 27 Nov 2010 03:35:38 -0500 (EST)

I am trying to figure out how to get current values of Graphics3D 
options ViewPoint, ViewVector, ViewMatrix et al, that change when one 
uses an ordinary mouse to move and spin a displayed object by 
click-and-drag.  I tried the obvious things like $ViewPoint, to no 
effect.  Now, the Front End must know these things, and probably exposes 
them in some way, perhaps as strangely-named variables.

The reason to ask is that I want to transform raw input from a 3D mouse 
(SpaceNavigator) such that the metaphor that observed object motion 
mimics 3D mouse motion regardless of how much (ordinary mouse click and 
drag) manipulation of the displayed plot has occurred.  

To effect this transform, I need to know the current transform from 
object space to user viewport space, so I can back-transform 3D mouse 
data from user space to object space.

Thanks,

Joe Gwinn