New glossy translucent material

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Re: New glossy translucent material

Postby patro » Wed Dec 08, 2010 5:18 am

nice test dobz :)
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Re: New glossy translucent material

Postby binarycortex » Fri Jan 14, 2011 11:15 pm

It appears to me that the current implementation of glossy translucent is not physically correct. Shown below is a marble texture on the diffuse channel of a glossy translucent material. On the chest it looks like the marble has veins of onyx, but in the wing it looks like veins of quartz. The link to an actual picture of marble shows the darker areas of the stone transmit less light. That is what I would expect to see.

glossy_trans_wrong.png
current implementation

very glossy translucent rock

Edit:
cornell-box.png
What i would expect to see
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Re: New glossy translucent material

Postby jeanphi » Sat Jan 15, 2011 7:19 am

Hi,

The current implementation is that the light that's not reflected is transmited, so yes, dark reflecting ares will transmit more light so you have to tweak the transmission color so that dark reflecting areas will also transmit less light (using the same texture, but perhaps different colors).
Thats because physically the light enters the marble, is reflected/absorbed and then exists. In dark areas there's more absorption. You could eventually model your marble with uniform reflection/transmission colors and just change absorption/scattering properties (it could work right now but due to the absence of support for non homogeneous media it might not give the expected result).

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