[osg-users] Performing zooming and other navigations on geocentricvirtual earch?

Paul Melis paul at science.uva.nl
Tue Mar 24 07:22:03 PDT 2009


Paul Martz wrote:
> (Posting this for about the 1000th time...)
>
> Zooming merely changes the field of view without changing the view position.
> Think of a photographer changing lenses on a camera without changing his
> physical location. You change the projection matrix to change the field of
> view, not the modelview matrix.
>   
But that's *your* definition of zooming...
> If you want to move the view position closer to a location, or further away
> from a location, then you would change the modelview matrix (Camera view)
> for that.
>   
Which is what the OP asks about (he does not ask about the projection 
matrix)

Regards,
Paul (#2)
> See the OpenGL red book.
>
> Paul Martz
> Skew Matrix Software LLC
> http://www.skew-matrix.com
> +1 303 859 9466
>
> -----Original Message-----
> Subject: [osg-users] Performing zooming and other navigations on
> geocentricvirtual earch?
>
> Hi,
>
> I have created geocentric(spherical) virtual earth and wanted to do navigate
> around the earth using keyboard including zooming-in and out.  As I m new
> to OSG I want to understand dat could it be done by setting
> viewmatrixAsLookAt of  views' cameramanipulator? Plz get me some ideas how
> it can be done???
> ... 
>
> Thank you.
>
> ------------------
> Read this topic online here:
> http://forum.openscenegraph.org/viewtopic.php?p=9054#9054
>
>
>
>
>
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>
>   




More information about the osg-users mailing list