Front and back material transparency (aka light invisible object)

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marcatore
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Re: Front and back material transparency (aka light invisible object)

Post by marcatore » Mon Mar 18, 2019 12:01 pm

Is it something that it needed to be implmented in the Blender Addon to try it?

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Dade
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Re: Front and back material transparency (aka light invisible object)

Post by Dade » Mon Mar 18, 2019 2:33 pm

marcatore wrote:
Mon Mar 18, 2019 12:01 pm
Is it something that it needed to be implmented in the Blender Addon to try it?
Yes, it has do add the support 2 node sockets instead of the current one (so you can plug in different front/back opacity).
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B.Y.O.B.
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Re: Front and back material transparency (aka light invisible object)

Post by B.Y.O.B. » Mon Mar 25, 2019 1:55 pm

I have implemented support for this feature with a new node that can be found in the material category:
https://youtu.be/q3UqoVAYzvw
(this is already in v2.2alpha1)
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marcatore
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Re: Front and back material transparency (aka light invisible object)

Post by marcatore » Mon May 27, 2019 1:01 pm

It seems that this feature it's not compatible with "Direct Light Sampling Cache" light strategy.

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Dade
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Re: Front and back material transparency (aka light invisible object)

Post by Dade » Mon May 27, 2019 2:00 pm

marcatore wrote:
Mon May 27, 2019 1:01 pm
It seems that this feature it's not compatible with "Direct Light Sampling Cache" light strategy.
I have never tried, do you have test scene showing the problem ?
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lacilaci
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Re: Front and back material transparency (aka light invisible object)

Post by lacilaci » Mon May 27, 2019 2:45 pm

Dade wrote:
Fri Mar 15, 2019 11:12 am
I have ever rejected the idea of having light invisible objects because it wasn't possible to have a consistent and coherent implementation when tracing rays both backward and forward (i.e. BiDir, PhotonGI, etc.).
There are plenty inconsistencies between bidir and path tracing options already, even multiplied by using or not using gpu, or metropolis sampler, no shadow catcher or gpu rendering or photongi for bidir, etc etc... Then there are ton of suboptimal features like tiled rendering, weird non-working combinations like tiled renderin and metropolis and clamping and god knows what can be mixed up to break luxcore.

Inconsistencies are no reason why luxcore shouldn't have features that make it on par with other modern renderers.

If you have a complex or semi-complex project build for luxcore you cannot simply switch from pathtracing to bidir or vice versa without readjusting or even completely forgetting about certain features and options and getting a different look.

Pushing features aside cause bidir can't do them makes no sense, just as making super weird workarounds that have near no application in any kind of production.

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Re: Front and back material transparency (aka light invisible object)

Post by marcatore » Mon May 27, 2019 3:05 pm

Dade wrote:
Mon May 27, 2019 2:00 pm
I have never tried, do you have test scene showing the problem ?
Here we are.
FrontBack_DLSC.zip
(93.55 KiB) Downloaded 44 times

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Dade
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Re: Front and back material transparency (aka light invisible object)

Post by Dade » Tue May 28, 2019 9:23 am

marcatore wrote:
Mon May 27, 2019 3:05 pm
Dade wrote:
Mon May 27, 2019 2:00 pm
I have never tried, do you have test scene showing the problem ?
Here we are.
FrontBack_DLSC.zip
I should have fixed this problem.
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Re: Front and back material transparency (aka light invisible object)

Post by marcatore » Tue May 28, 2019 12:20 pm

Dade wrote:
Tue May 28, 2019 9:23 am
I should have fixed this problem.
Thank you.
I'll check it next build comes out

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Re: Front and back material transparency (aka light invisible object)

Post by marcatore » Wed May 29, 2019 12:46 pm

Fixed!

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