[R] Defining origin for rotation in RGL device

[Duncan Murdoch]

On 25/04/2011 5:46 AM, Mark Heckmann wrote:
> Hi all,
>
> How can I tell RGL to set the center for the rotation to the origin of  the coordinate system (0,0,0).
> It seems that the default is to use the center of the display not the origin of the coordinate system.
>
> open3d()
> lines3d(c(0, 1), c(0,0), c(0,0))
> lines3d(c(0,0), c(0, 1), c(0,0))
> lines3d(c(0,0), c(0,0), c(0, 1))
>

You can attach any transformation you like to a mouse button.  See the 
"mouseCallbacks" demo for R implementations of the standard ones, and 
modify the mouseTrackball function there to choose the position of the 
origin of the coordinate system as the centre of rotation.

Duncan Murdoch