Re: IDL virtual reality (was 3D Object IDL )

["Rick Towler" <rtowler(at)u.washington.edu>]

"Pavel A. Romashkin" <pavel.romashkin@noaa.gov> wrote in message
3B71CF9C.BE64EAFD@noaa.gov">news:3B71CF9C.BE64EAFD@noaa.gov...
> Rick Towler wrote:
> >
> > If you need them to cross at some focal point
> > (which I assume real eyes do) you will need to set the LOOKAT value to
some
> > point on the horizon (for example lookat=[0,0,-20])
>
> So, not just my eyes after a day at the computer are crossed behind the
> back of my head - [0,0,*-20*]?
> This makes me feel better :-)

Ha hahaha.  That's why my head hurts at the end of the day  |-)

IDL OG uses a right handed coordinate system where +Z is coming out of the
screen. By default a IDLgrView places the viewer at some +Z value looking
back torwards the axis on a vector [0,0,-1].  My camera does the same.  So
the camera would be at some point say [0,0,10] looking along a vector
[0,0,-1] past the orgin to [0,0,-20] off in the distance. You probably know
this.

So you must be giving me a hard time about how I was unconventional with
"eye space" coordinates and "world space" coordinates.  Typically viewing
systems like my camera use LHCS's (or so the literature says) but I have
never used any other "camera" viewing systems and the way my camera
developed just seemed natural for IDL users.

-Rick

> Cheers,
> Pavel