From: Angus Dorbie (dorbie++at++sgi.com)
Date: 09/05/2000 11:09:15
Yes, it's called double-snow.
Cheers,ANgus.
Max Waterman wrote:
>
> Doesn't this effect has a special name?
>
> Max.
>
> Dick Rous wrote:
> >
> > If your framerate is less than the refresh rate of your dispay (e.g. 30 vs.
> > 60 Hz.),
> > the what you see are so calledmultiple images. These occur when objects have
> > a substantial angular velocity with respect to the eye. It is a visual
> > "deceiption", caused
> > by the snowflakes being twice rendered in the same spot, then shift to the
> > next position in
> > time, where again they are rendered twice.
> > You will notice the same effect when your simulation moves the eyepoint
> > along a road.
> > Thin vertical objects alongside the road seem to "double" when the angular
> > velocity increases.
> > The solution is to make your framerate equal to the refresh rate. (by
> > optimising your
> > database or/and adding gfx hardware) .:-)
> >
> > Cheers,
> >
> > Dick.
> > __________________________________________________________
> > Dick Rous SGI - European Technical
> > Support
> > email: dick++at++sgi.com
> > phone: +31-35-6423160 fax: +31-35-6423162 VNET: 955-6868
> > __________________________________________________________
> >
> > -----Original Message-----
> > From: Hui Li [mailto:huili++at++mail.sc.cninfo.net]
> > Sent: 02 September 2000 15:02
> > To: info-performer++at++sgi.com
> > Subject: Is it because of Phase lock?
> >
> > I try to simulate snow flakes on a 2 cpu onyx2.
> >
> > what I do is draw the snow flakes at the draw call back. However, what i saw
> > on the screen
> > the flakes becomes doubled, each flakes seems be draw twice on it's drop
> > pass, when i slow
> > down the speed or freeze simulation, it looks
> >
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