Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] General Discussion => Topic started by: Tanakov on 2019-07-09, 10:31:13

Title: Image to IES? Fake Caustics? - No more :(
Post by: Tanakov on 2019-07-09, 10:31:13
Hello,
as Im working on a project that requires me to create a bit of fake light using IES method, I was met with unfortunate news, IES GEN no longer works with Corona.

(https://mir-s3-cdn-cf.behance.net/project_modules/max_1200/dc131e62696861.5a985da40c4eb.jpg)

So this effect is no longer possible with Corona 4.0

Question?

Is there someone who knows a way how to convert Images to IES?

Best Regards


Title: Re: Image to IES? Fake Caustics? - No more :(
Post by: maru on 2019-07-09, 10:43:24
This is related to this forum thread:
https://forum.corona-renderer.com/index.php?topic=11630.0

I will later check how it works in V4, but if anyone is interested in this and/or has MAXScript experience, any help is welcome. :)
Title: Re: Image to IES? Fake Caustics? - No more :(
Post by: Tanakov on 2019-07-09, 11:30:18
I managed to create the IES using

2019 / Corona 2 / IES Gen 1.0

So A bit of time-travel there, but it worked.

The biggest downside of this method is that you have to deal with a quite low-resolution image, so the patterns are never that sharp.

But still better than calculating regular passes.
When I load the IES into my light I found a few problems:
- Light suddenly acts like 10m polygon mesh, lagging a lot.
- IES > "on" when toggled off still works with IES
- Super slow Render Start when using IES in 4.0

Title: Re: Image to IES? Fake Caustics? - No more :(
Post by: maru on 2019-07-10, 13:15:12
I just tested this with Corona V4 Hotfix 1 and 3ds Max 2020.
I followed this guide: https://forum.corona-renderer.com/index.php?topic=11630.0
Everything works fine here.

Here are my notes:
1) Nothing happens when I drag-and-drop the script into the viewport, but I can find it in Customize user interface > Toolbars > #PankovScripts , then just drag-and-drop into the UI
2) The first time I clicked "Create IES to..." it said "Operation canceled" and did not proceed with rendering. So I just pressed the button again, and it worked. I think it just needs to "fill" the empty Max VFB with anything before rendering.
3) I can confirm the slowdown with IES in V4, but this happens only with this custom IES file. Regular IES shipped with Corona work fine. I guess it's because of the complexity of this custom IES. You can compare them by opening them in notepad.

Conclusion: everything is fine and works with Corona 4 in MAx 2020.
Title: Re: Image to IES? Fake Caustics? - No more :(
Post by: Tanakov on 2019-07-19, 23:19:05
I just tested this with Corona V4 Hotfix 1 and 3ds Max 2020.
I followed this guide: https://forum.corona-renderer.com/index.php?topic=11630.0
Everything works fine here.

Here are my notes:
1) Nothing happens when I drag-and-drop the script into the viewport, but I can find it in Customize user interface > Toolbars > #PankovScripts , then just drag-and-drop into the UI
2) The first time I clicked "Create IES to..." it said "Operation canceled" and did not proceed with rendering. So I just pressed the button again, and it worked. I think it just needs to "fill" the empty Max VFB with anything before rendering.
3) I can confirm the slowdown with IES in V4, but this happens only with this custom IES file. Regular IES shipped with Corona work fine. I guess it's because of the complexity of this custom IES. You can compare them by opening them in notepad.

Conclusion: everything is fine and works with Corona 4 in MAx 2020.


Any information on the IES slowdown? I would like to know how I can make it go away :)
Title: Re: Image to IES? Fake Caustics? - No more :(
Post by: maru on 2019-07-22, 17:54:47
Any information on the IES slowdown? I would like to know how I can make it go away :)

It's confirmed and logged in our internal system. I'll let you know here about any updates.
Maybe you can use a standard/photometric light as a workaround?