Re: Spec. Changes

Chris Schoeneman ([email protected])
Mon, 15 May 1995 13:04:32 -0700


> unfortunately the lighting model used in VRML is insufficient for the type
> of catalogs you're talking about. To be able to specify lighting in lumens
> requires an energy based lighting model.

Correct.

> However, specifying the vrml lighting equations in the spec. will allow
> you to export a model lit using an energy based model to a vrml
> browser. Without knowing the equations used for the lighting display,
> you will gave no way of ensuring that what the user sees is what you
> went to such pains to calculate.

If I've already calculated the lighting, why would I want the browser to
do any lighting at all? You can manage to avoid all lighting in the
current spec (by using only ambient or emissive colors) but it's not
pretty. This is why I'd like to see a LightModel node in 1.1 that would
at least allow me to turn off all lighting by the browser. I could then
leave my colors in the diffuseColor fields and rendering may even be
faster.

I think the lighting equations should remain an implementation detail.
The ability to turn off lighting may help make this more acceptable.

Cheers,
-chris