New absorption layer transmittance parameter

[OnoSendai]

I've added a new parameter to the specular material, called 'absorption layer transmittance'.
It simulates the absorption of light by a thin coating of material on the surface of the material.
It's a wavelength dependent parameter, and can thus be driven by a shader, texture, or be a constant colour.
It should be useful for a few things:
* Stained glass
* Surface absorption on surfaces like human skin ( spots, freckles etc..)
* Projecting images (film projector etc..)

I also plan to add the parameter to the glossy transparent material.

Here's a stained-glass like example:

[WytRaven]

Ohhhhh! Nice!

[OnoSendai]

I can't help but notice that you've posted the same message three times in a row, Wyt

[WytRaven]

...and each time heart felt or perhaps just foolish consistency?

[OnoSendai]

hahaha maybe foolish consistency

[psor]

That's great! Thanks so much for this Nik!
A question tho. What about those nasty flies?





take care
psor

[OnoSendai]

Psor: the fireflies are due to usage of specular material and small light source, and are unavoidable with QMC path tracing.

[fused]

was about to ask the same thing.

thats pretty awesome, ono

[psor]

Thanks Nik, good to know.




take care
psor

[OnoSendai]

Same scene, but using a glossy transparent material:

[psor]

Neat! Could you please do another one with "god rays"?!





take care
psor

[fused]

Hey Nick, what about some xml so we can start implementing that for our beloved customers?

[Whaat]

Looks very useful nick! (That was fast...) I hope this is a material parameter and not a medium parameter.

[OnoSendai]

Hey Nick, what about some xml so we can start implementing that for our beloved customers?

It's pretty simple, it looks like this:

Code: Select all

<specular>
			<transparent>true</transparent>
			<internal_medium_name>spec_medium</internal_medium_name>

			<absorption_layer_transmittance>
				<texture>
					<texture_index>0</texture_index>
				</texture>
			</absorption_layer_transmittance>

			<texture>
				<uv_set>albedo</uv_set>
				<path>ColorChecker_sRGB_from_Ref.png</path>
				<exponent>2.2</exponent>
			</texture>
		</specular>

[OnoSendai]

Neat! Could you please do another one with "god rays"?!





take care
psor

I'll leave that up to you guys