Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => Topic started by: 3di on 2017-08-19, 02:30:15

Title: Shadow catcher not reflecting lights
Post by: 3di on 2017-08-19, 02:30:15
shadow catcher doesn't reflect corona light material.  it does reflect self illumination though..
Title: Re: shadow catcher
Post by: 3di on 2017-08-19, 02:57:14
correction, the reflection of the object with the corona light material doesn't appear in the shadow catcher reflections when the corona light material is applied directly to the object....but it does appear in the shadow catchers reflections when applied within a multi/sub-object map.  In this instance it appears in the beauty pass but not in the alpha channel meaning it cant be used for compositing.
Title: Re: shadow catcher
Post by: 3di on 2017-08-19, 03:17:55
I've just tried using corona lights instead of light material, and they also dont reflect in the shadow catcher.  Shadow catcher bug then?
Title: Re: shadow catcher
Post by: maru on 2017-08-21, 16:25:55
Have you tried the "shadowcatcher illuminator" option in both the Corona Light and Light mtl? ;)
Title: Re: shadow catcher
Post by: 3di on 2017-08-23, 02:41:48
Hi Maru I'm now using version 1.6.2 and now the opposite is happening.  The lights reflection is white in the renders alpha channel (as it should be), but in the beauty pass it's showing as black.....

[EDIT] Strangely it's now gone back to the the previous behaviour of subtracting the lights reflection from the alpha channel [EDIT]

I've also tried turning shadow catcher illuminator on, but this just seems to stop the light reflecting at all in the shadow catcher...or even more strangely, intermittently has no effect at all.

steps to recreate.


I should point out that everything works correctly when choosing alpha mode "always solid".

Please see attachments for better understanding.
Title: Re: shadow catcher
Post by: maru on 2017-08-25, 11:55:12
Ok, moved back to bug reporting, sorry for the hassle.

It might be by design, as explained here: https://forum.corona-renderer.com/index.php?topic=7935.msg62666#msg62666
So if the lighting or reflection would be visible, it probably wouldn't be possible to composite it correctly.
But I will leave this thread here unless the developers decide to move it back to resolved.

Currently I cannot find any solution to this, other than loading the backplate directly in Max, and rendering the image with the shadowcatcher in "solid" mode instead of "for compositing".
Title: Re: shadow catcher
Post by: 3di on 2017-08-25, 12:14:32
Thanks Maru. 

Unfortunately that workaround isn't possible as the client wants to the option of changing the background himself occasionally.