Roger Morris (rmorris++at++tswl.co.uk)
Fri, 24 Jan 1997 09:17:35 -0800
Don't get confused between light SOURCES (which is what Ken is talking about)
and light POINTS (which can be drawn calligraphically, as Axel describes, but
don't illuminate the scene, no matter how bright they get!).
Ken, are you using DECAL textures? These are unaffected by shading. You
should
use modulated textures on a white polygon, instead.
> From: axel++at++elwood.hannover.sgi.com (Axel Sammet), on 24/01/97 09:02:
> Hi Ken
>
> The problem with commonly available diplays is, that they give every pixel
> the same amount of time. Therefore the intensity is physically limited and
> you need a longer drawing time for the Cathod Ray for the bright lights
> sources to become REALLY bright.
> This is commonly referred to as calligraphic lights and performer in
> Infinite Reality supports the control of a calligraphic lights board from
> EIS.
> All the bright lights are drawn in the vertical retrace phase of the
> drawing phase and allows you to place quite a number(several thousand) of
> calligraphic lights in this period. However, it reduces the time available
> to draw the initial frame.
> Be sure you really need these bright lights, since the board and the
> Diplays/Projectors are pretty expensive.
>
> Let me know if you need more details/contacts.
>
> Axel
>
> On Jan 23, 16:15, ken sartor wrote:
> > Subject: very bright lights
> >
> > Greetings,
> >
> > For an effect that i am trying to achieve, it would be
> > very nice to have *EXTREMELY* bright lights... But, when
> > i just naively crank up the light, i do not get the
> > effect i want. What happens is that all the geometry
> > is affected in the way i want (when the light is sufficiently
> > bright, it turns white) but the texture is clamped to some
> > value (objects that are textured and already on white
> > geometry are unaffected by brightning the light source
> > above 1).
> >
> > The effect i want is for all objects to be brightened by
> > the extremely bright light source and, if it is sufficiently
> > bright, to turn white. Is there some way to achieve this
> > effect? Note that i want a method that will do this generally
> > for various databases (i.e., i don't want to depend on
> > custom made databases).
> >
> > Thanks in advance!
> >
> > ken
> >
> > =======================================================================
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> >-- End of excerpt from ken sartor
>
>
>
> --
>
> _____________________________________________________________________
>
> Axel Sammet, SE
> Visual Simulation
>
> Silicon Graphics GmbH | Tel: +49 511 90172-29
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> 30659 Hannover | VM #: 59191 M/S: IDE-3140
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> _____________________________________________________________________
> =======================================================================
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>
>
==========================
Roger Morris TRANSFORMATION SOFTWARE
Applications Engineer Thame Park Road
TEL: 01844 261456 Thame
FAX: 01844 260056 Oxon, OX9 3UQ
E-mail: rmorris++at++tswl.co.uk
==========================
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