Re: [ROOT] Setting Viewpoint in TView and/or X3d

From: Rene Brun (Rene.Brun@cern.ch)
Date: Fri Dec 20 2002 - 10:32:01 MET


Hi Ben,

With the recent introduction of the perspective view in 
the pad it makes sense to implement your request.
There is no method yet in TView or x3d to set the viewpoint. 
The extent  of the viewable objects is automatically computed, 
then the viewpoint is  computed according to this extent and 
the viewing angles. Then the only  thing you can do is 
re-scaling(parralel) /changing the view distance (perspective) 
in order to zoom in/out, rotate the view or move it on x/y 
axis of the screen.
Of course this can be done - one example is the way we grab 
the focus of an object with different extent, but there we 
also compute the viewpoint  automatically. 

We will add a method to do what you want in TView when
in perspective mode.

Rene Brun, Andrei Gheata

On Thu, 19 Dec 2002, Ben Morgan wrote:

> Hi ROOTers,
>            I think this question has been asked before, but I couldn't 
> find an answer in ROOTtalk, or in the documentation. I've generated a 
> geometry to be viewed in a TView and the x3d viewer, and in the latter 
> case is it possible to set the actual x,y,z point the geometry is viewed 
> from? I need to do this because the origin is the optimum viewpoint for my 
> geometry, but the default viewpoint is outside the actual volume of 
> interest.
> 
> I know one can use the ExecCommand method to move through the view, 
> but it's not particularly accurate. Any advice would be gratefully 
> received! I'm using ROOT v3.04/02 on a RH7.1 PC. Thanks,
> 
> Ben Morgan.
> 
> 
> -- 
> -------------------------------------------------------------------------------
> Mr. Ben Morgan                               Tel: 44 (0)114 22 23553 (Work)
> Postgraduate Student
> University of Sheffield
> Department of Physics & Astronomy
> Hicks Building
> Hounsfield Road
> Sheffield  S3 7RH
> -------------------------------------------------------------------------------
> 



This archive was generated by hypermail 2b29 : Sat Jan 04 2003 - 23:51:24 MET