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Why objects should retain the options for shadows in Raytracing

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VBSmiles:
The first image uses no shadows.

Its a great photo on it's own, BUT...

The second image used shadows.... note that the light source sits in the lamp. A big oops.

I took off the 'light' here to show what should be ( shadows with more emphisis than intended to bring focus to them )

If you ever decide to introduce self illuminating objects, you'll probably want to deal with this issue.

Oh,  I know how tough it would be to introduce shadows in the raytracer as it was in scanline. So don't blame ya if you never get it done  :-*

Steve:
I don't understand what you did for images 2 and 3.    Are they made with ART or the scanline renderer?  The missing feature from ART is the ability for each object to cast shadows or not.  They all cast shadows at 100% dark.  The scanline renderer allows them not to and to only cast a partial shadow.

VBSmiles:
Sorry if I didn't state it clearly enough. All 3 photos used the ART renderer. And the missing feature in
ART is what I was refering too. Without this option it's pretty useless to use an object as a light source properly with shadows enabled.

in image 2 the light is inside the object with shadows enabled, ( which is to be expected in a lamp )
In image 3 I showed how it should be by taking out the object blocking all the light. ( or causing everything to be shadowed improperly )

As for casting shadows at 100% dark, I never noticed this to be the case.... thanks for the insight  :P

Steve:
I think I see.  You mean that the lamp in #2 has glass in the holes that is shadowing the light.  There are several ways to solve that.  By far the best one is to add photon mapping.  It is a very advanced way to model global lighting, probably the best practical technique known.  It could do caustics, glossy reflected light, diffuse irradiance, etc.  I would like to add that to ART in the near future but it would take about 3-6 months I think.

The second best way is to model transparent shadows.  It wouldn't handle dielectrics properly - they'd behave like transparent gels - and would slow down shadows.  Not nearly as difficult to do though.

The third way is to allow disabling of shadow casting by individual objects.  Not a very realistic solution - a real hack really - but fairly easy to do.  Would possibly slow down shadows a bit.

hihosilver:
I think being able to disable shadows for certain objects would be nice.  Even though it's not realistic, art often isn't realistic!
Of course photons, caustics, all that jazz would be amazing!

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