Author Topic: Caustics playground!  (Read 29133 times)

2019-04-23, 20:27:19

maru

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Today marks the day when Corona + Caustics became reality!
We hope that you are as excited as we are, and that you will share your experiments in this thread!

The daily build is available to all license holders. Info and download:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000570015

The new caustics can be enabled with a checkbox in the Performance tab.

Any tests are welcome, and we are super interested in your feedback.

More about using the new caustics on the helpdesk:
https://coronarenderer.freshdesk.com/support/solutions/articles/12000056738
Marcin Miodek | chaos-corona.com
Chaos Corona Support Team Lead | contact us

2019-04-23, 20:36:15
Reply #1

jms.lwly

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This looks great - can't wait to give it a try!

2019-04-23, 21:03:45
Reply #2

Frood

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Inevitable one.


Good Luck



Never underestimate the power of a well placed level one spell.

2019-04-23, 23:44:04
Reply #3

shoebu23

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Congrats team- a beer is in order! Quick shots focusing on reflective vs. refractive. 

Suggestion:  My shop does a lot of work in visualization for glass products, and one thing that helps a lot is controlling the caustics in post (thank you for including a separate pass for caustics).  However- what would be great is if we could control it directly in the VFB for Corona.  Is it possible to figure out a way to treat the caustics like a light in lightmixer so we essentially turn it up/down via exposure?  A further suggestion (and I'm sure more complicated for denoising), would be to have a checkbox next to the light in lightmixer so you can turn each light's caustics up/down in-render.

Thanks again- looking great!

2019-04-24, 01:59:59
Reply #4

Noah45

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I have absolutely no need for this in my workflow, but damn if don't think this is cool. Have fun
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2019-04-24, 02:27:12
Reply #5

snakebox

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So much need for this! love it!  15min's at 2500px wide, no denoise on a shitty 4core i7.  (looks like the image size was lowered through something, could have been FB where it was posted before I remembered this thread. anyway it's looking really promising!

lit with a single hdri.

2019-04-24, 04:21:50
Reply #6

snakebox

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I don't know or really think it has to do with the new caustics per say, but it's very clear that using an hdri with a more complex glass object, generates some nasty fireflies, made super obvious here with dispersion as they are all coloured.

I am running denoise "remove fireflies" on 1.0 in this test.  Is there any way around this?

2019-04-24, 07:32:29
Reply #7

aaouviz

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Super exciting news guys! Well done.

I did a very quick test, see attached. I'm getting a sort of double shadow (one shadow, in the correct place according to the location of the sun, and the offset caustics). Is this normal, physically behaviour?

Seems kinda wrong to me. Am I missing something?
Nicolas Pratt
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https://www.instagram.com/anotherangle3d/

2019-04-24, 09:07:03
Reply #8

Ondra

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Super exciting news guys! Well done.

I did a very quick test, see attached. I'm getting a sort of double shadow (one shadow, in the correct place according to the location of the sun, and the offset caustics). Is this normal, physically behaviour?

Seems kinda wrong to me. Am I missing something?
yes, it is normal, since the geometry setup is unphysical. It will look better if you model it properly
Rendering is magic.
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2019-04-24, 09:14:46
Reply #9

maru

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Seems kinda wrong to me. Am I missing something?
If you would like the caustics to perfectly overlap with the shadow, you would have to set IOR of that material to 1.0. ;)
Marcin Miodek | chaos-corona.com
Chaos Corona Support Team Lead | contact us

2019-04-24, 09:46:43
Reply #10

aaouviz

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Thanks for the feedback guys.

Another issue discovered (though its working pretty damn well and I'm loving this!).

I'm using displacement map for the waves in this pool. It's working well, very fast. However, I'm guessing the calculations of the displacement are causing problems with the projection of the caustics. See two attachments - the first (camera) is incorrect, the caustics stop (near the black line - coincidental), however, if I change the view slightly (so more of the pool is visible) and restart the render, the caustics renders properly. If I then switch back to the camera view (without restarting the render) the caustics renders properly from the camera.

I hope this makes sense - happy to share scene if helpful. Any suggestions how I might overcome this problem?
Nicolas Pratt
Another Angle 3D
https://www.instagram.com/anotherangle3d/

2019-04-24, 09:52:32
Reply #11

soso

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Don't get me wrong, this features is one of the killer features, and it's so useful in many cases. But, because of the overwhelming NaNs pixels and slow render time, it is kinda useless in animation productions...

2019-04-24, 10:42:04
Reply #12

Tanakov

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Without wasting time I started working with caustics, so my results were weird at the beginning.

The issue you see on "Test 02" was caused by a missing texture, on a network path that wasn't even part of this shot.

Other than that MAN can't wait to try my water splashes now!
Corona since 2014.06.02
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2019-04-24, 12:32:50
Reply #13

maru

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Thanks for the feedback guys.

Another issue discovered (though its working pretty damn well and I'm loving this!).

I'm using displacement map for the waves in this pool. It's working well, very fast. However, I'm guessing the calculations of the displacement are causing problems with the projection of the caustics. See two attachments - the first (camera) is incorrect, the caustics stop (near the black line - coincidental), however, if I change the view slightly (so more of the pool is visible) and restart the render, the caustics renders properly. If I then switch back to the camera view (without restarting the render) the caustics renders properly from the camera.

I hope this makes sense - happy to share scene if helpful. Any suggestions how I might overcome this problem?

Either switch to "World size" displacement in the Performance tab (this will calculate displacement globally, not just for the camera view, but may be slower and more RAM-consuming), or use this string option:

float geometry.displace.maxSizeScreenOutFrustumMultiplier = 1

More on string options: https://coronarenderer.freshdesk.com/support/solutions/articles/5000518663-string-options
Marcin Miodek | chaos-corona.com
Chaos Corona Support Team Lead | contact us

2019-04-24, 12:33:35
Reply #14

maru

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Don't get me wrong, this features is one of the killer features, and it's so useful in many cases. But, because of the overwhelming NaNs pixels and slow render time, it is kinda useless in animation productions...
Please send us any scenes where you are getting NaNs and slow rendering. We will do our best to fix it!
Also, we have not encountered any NaNs in our internal tests, so your help is invaluable!
Marcin Miodek | chaos-corona.com
Chaos Corona Support Team Lead | contact us