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View Full Version : Translucency-- affected by 'closed volume' issues?



jeric_synergy
03-16-2013, 10:18 PM
Does translucency 'care' whether a volume (mesh) is enclosed or not? 'Watertight', w/o any gaps?


Tnx!

Sensei
03-17-2013, 01:50 AM
Translucency (and specularity) are pure CG effects. In real world it's result of bouncing light and/or light passing through partially transparent material.

How to calculate diffuse and translucency?

float value = dot product( light_sample_direction, surface_normal );
if( value > 0.0 )
{
// we call it translucency
value = value * surface->translucency;
}
else
{
value = -value;
// we call it diffuse
value = value * surface->diffuse;
}

Translucency doesn't care about anything.. It's calculated in the same line of code as diffuse.

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jeric_synergy
03-17-2013, 02:24 AM
Thanks Sensei. What about SSS? Does that require a watertight volume?

Sensei
03-17-2013, 02:35 AM
That depends on internal algorithm of particular shader/node. Well, it's internal.
So we can only render and see what happens and make conclusions from observations.