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Re: Cold Fusion

Posted: Mon Jan 29, 2018 3:28 pm
by Dade
Sharlybg wrote:
Mon Jan 29, 2018 3:26 pm
typo error :

I still fear the first result can't be achieve with laser :?
Use spot light sources and/or fix the cauchy value you used: it is very small, if you want drammatic rainbows, use something in the range of [0.1, 0.2].

Re: Cold Fusion

Posted: Mon Jan 29, 2018 3:49 pm
by B.Y.O.B.
kintuX wrote:
Mon Jan 29, 2018 1:57 pm
Maybe because they were set to 0 W & 0 efficiency ;)
It is perfectly ok to use 0 W and 0 efficacy. In such a case the brighness is only controlled by the gain.
It's a bit counter-intuitive, I know.
Only if you set the gain to 0 you get a "switched-off lightsource".

Re: Cold Fusion

Posted: Mon Jan 29, 2018 3:49 pm
by Asticles
Astonishing images!

Re: Cold Fusion

Posted: Sun Jun 09, 2019 6:49 pm
by p2or
Dade wrote:
Mon Jan 29, 2018 2:13 pm
Ah, got it, the world has no volumes so all the rays starting from the camera travels into the void. The solution is to set the default world volume (or to set the prism and all other objects outside volume).
Hey guys,

many thanks for this great example. However, I can't get the lasers showing up the right way, even when the world volume is set. What do I need in order to make that work? Any advice would be awesome.

Thanks & Cheers,
Christian

Re: Cold Fusion

Posted: Sun Jun 09, 2019 7:44 pm
by B.Y.O.B.
Have you fixed the volume setting of the world? Dade found that it was wrong in the .blend:
viewtopic.php?f=3&t=75&start=20#p1071

Re: Cold Fusion

Posted: Sun Jun 09, 2019 8:36 pm
by p2or
B.Y.O.B. wrote:
Sun Jun 09, 2019 7:44 pm
Have you fixed the volume setting of the world? Dade found that it was wrong in the .blend:
viewtopic.php?f=3&t=75&start=20#p1071
Thanks for your quick reply @B.Y.O.B. Yep, already tried adding a homogeneouse volume to the enviroment. The outcome is also pretty nice but looks quite different ;) . Not sure what I'm doing wrong...

Re: Cold Fusion

Posted: Sun Jun 09, 2019 9:21 pm
by B.Y.O.B.
When I use a homogeneous world volume with default settings, it looks to me like I get a correct result.
I disabled all but one laser so the result can be checked easier.
By the way, I have switched to Metropolis sampler which is better for these kind of scenes.

There's still no option to set the volume of lights, I wonder if that plays a role here.

Re: Cold Fusion

Posted: Mon Jun 10, 2019 4:16 pm
by p2or
Thanks again @B.Y.O.B. Yessssss! You are correct, my fault. I've accidentally added another interior to the bounding volume while fiddling with the values. Now we're getting something similar, brilliant! Also the outcome is indeed way nicer using metropolis sampling, thanks for adjusting my render settings.

However, I wonder why the actual prism has no depth to it...? What I'm missing here?

Thanks & Cheers,
Christian

Re: Cold Fusion

Posted: Mon Jun 10, 2019 4:53 pm
by B.Y.O.B.
p2or wrote:
Mon Jun 10, 2019 4:16 pm
However, I wonder why the actual prism has no depth to it...? What I'm missing here?
The prism has no interior volume set (= clear volume), so the light just travels straight through and is not visible from any other than the outgoing direction.

In theory, the beams would become visible if you use a homogeneous volume for the interior of the prism.
However, I could not get them to show even with that - I suspect that these are SDS paths (specular-diffuse-specular) which Bidir is unable to render.
Maybe Dade can comment if this is correct.

By the way, try a clear volume with colored absorption for the prism. Looks quite cool.

Re: Cold Fusion

Posted: Mon Jun 10, 2019 6:54 pm
by Dade
B.Y.O.B. wrote:
Mon Jun 10, 2019 4:53 pm
In theory, the beams would become visible if you use a homogeneous volume for the interior of the prism.
However, I could not get them to show even with that - I suspect that these are SDS paths (specular-diffuse-specular) which Bidir is unable to render.
Maybe Dade can comment if this is correct.
Yes, you are but you could remove the top face of the prism (or extrude the prism up to the point to include the camera) so it is not an SDS path anymore (i.e. you are removing the specular surface).