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pixelinfected
01-14-2004, 12:21 AM
i find a strange thing.
i did a simple glass obj, if i enable caustic, shadow loss its color, and transparency.
i know that caustic change light direction, but not change transparency.
at top there are scene with caustic enable, and bottom with caustic disable.

any one have a suggest?

http://www.carlomacchiavello.com/temp/caustic-bug.jpg

a sample scene is here bugcontent.zip (http://www.carlomacchiavello.com/temp/bugcontent.zip)

garg
01-14-2004, 02:05 AM
The best thing is to test with real world things. Try to reproduce you scene with a real word glass ball (colored) and check what should be the correct result.

Normaly it should give you something very similar the the first result as all the rays going throug the sphere should be concentrated in one spot that means you will have a black shadow with a bright colored spot in the middle.

Alain Bertrand

pixelinfected
01-14-2004, 11:18 PM
uhm could you tell how can disable caustic in the reality?
;-)

ok, i just do this test, and in reality i have a colored shadow with a caustic light concentration.

hcoat
01-15-2004, 12:11 AM
In reality caustics work like the top pic.
Light is bent and redirected, where the light lands it leaves the color of the obj it is passing through and it cast dark shadows where light doesn't make it through because it was redirected.

If you still want a colored shadow and the caustics clone your light leave it in the same place and turn off caustics, affect diffuse and affect specular on one light.
now you will get both but this is not realistic.