Re: openGL and Performer
Angus Dorbie (dorbie++at++sgi.com)
Wed, 20 May 1998 13:18:57 -0700
Craig Materick wrote:
>
> If the routine that draws the stars is just that, a routine that draws
> points. How exactly does one tie that in to the scene graph so that it
> draws all the points each frame? Essentially, I have an openGL function
> which draws points, and I need these points to be able to move and be
> redrawn each frame according to some DCS in the scene graph. How does the
> routine to draw the points become a "node"?
>
> Thanks,
>
> Craig Materick
>
> On Wed, 20 May 1998, Angus Dorbie wrote:
>
> > Craig Materick wrote:
> > >
> > > Just wondering if there is a straight-forward way to include an openGL
> > > rendering routine(which I have) to draw stars as point sources into a
> > > performer application which draws and animates the various bodies in the
> > > solar system. Currently, I am mapping a star map to a giant "Universe"
> > > sphere, but this is slow and not too nice to look at.
> > >
> > > Thanks in andvance for any information,
> > >
> > > Craig Materick
> >
> > Add the stars to the scene below a DCS, translate the DCS to the eye
> > position.
> > This will have the equivalent graphical effect of drawing at infinity so
> > you won't
> > need a huge sphere and will get better values for your CLIP plane
> > settings.
> >
> > Disable depth writes and draw first to avoid zbuffer problems.
> >
> > Cheers,Angus.
> > --
> > "Only the mediocre are always at their best." -- Jean Giraudoux
> >
> > For advanced 3D graphics Performer + OpenGL based examples and tutors:
> > http://www.dorbie.com/
> > =======================================================================
> > List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
> > Submissions: info-performer++at++sgi.com
> > Admin. requests: info-performer-request++at++sgi.com
> >
>
> =======================================================================
> List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
> Submissions: info-performer++at++sgi.com
> Admin. requests: info-performer-request++at++sgi.com
Use a draw callback on a group bellow a pfnode, but I'd advise using
a geoset with PFGS_POINTS primitives and not calling the gl.
Cheers,Angus.
--
"Only the mediocre are always at their best." -- Jean Giraudoux
For advanced 3D graphics Performer + OpenGL based examples and tutors:
http://www.dorbie.com/
=======================================================================
List Archives, FAQ, FTP: http://www.sgi.com/Technology/Performer/
Submissions: info-performer++at++sgi.com
Admin. requests: info-performer-request++at++sgi.com
This archive was generated by hypermail 2.0b2
on Mon Aug 10 1998 - 17:57:25 PDT