Page 2 of 2
Posted: Mon Jul 10, 2006 7:51 am
by Thomas An.
Plastics complicate maters because they are not trully opeque.
For example in your reference above both BP and 6F polymers have extinction coefficients nearly zero in the visible spectrum (it fluctuates up and down later). This means they behave more like dielectrics (not opeque).
It seems, many of the synthetic resins start off as transparent and then pigmentation is admixed to turn them opeque or give them a tint.
Posted: Tue Jul 11, 2006 4:14 am
by Tim Ellis
Thomas, do you have any ideas regarding a shadow only material, using your excellent information?
I have been trying to apply your information to do this, but keep running into problems.
Cheers,
Tim.
Posted: Tue Jul 11, 2006 4:46 am
by Tim Ellis
Basically *physical* behaviour is to have a material that is transparent except for shadows.
Not really physical, but a material that does not refract or reflect, but will show any shadows that fall on it.
I was trying to apply your nd info, to help create this.
Tim.
Posted: Tue Jul 11, 2006 4:53 am
by Thomas An.
Tim Ellis wrote:Basically *physical* behaviour is to have a material that is transparent except for shadows.
Not really physical, but a material that does not refract or reflect, but will show any shadows that fall on it.
I was trying to apply your nd info, to help create this.
Tim.
This is not physical behavior and thus not possible directly (your will have to apply some hacks or some post process)...
... if a material cannot reflect anything then you wouldn't see shadows either. (all objects reflect something otherwise they would be invisible)
Posted: Tue Jul 11, 2006 5:20 am
by Tim Ellis
Cheers Thomas, I've replied in the other thread so not to clutter up this one.
Tim.
