Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: zules on 2017-04-20, 15:57:39

Title: Very long pre-calculation...
Post by: zules on 2017-04-20, 15:57:39

Hi there,
I'm having a rude moment on a professionnal project... This is a not-ending rendering ! :D

12hXX something for a 4K picture, with displacement but not so much nor huge vegetation nor nothing special...

See the first rending, over, to see the actual scene.
Then, the pre-calculation never ending on an update for the same project.

For the scene :
- stone is displaced
- corona sun & sky
- HDRI override reflection
- Vegetation & car & characters in proxies

Nothing special I gess ?

I'm rendering it on a bi-xeon 2630v2 32Go RAM + 4 Nodes with i7 4790 16Go RAM... so pretty good set-up for a still work in 4K.

Can you help me to optimize this scene ?

Thx !

JG

Title: Re: Very long pre-calculation...
Post by: mferster on 2017-04-20, 23:31:24

hmmm you could try rendering isolated objects one by one to determine the offending problem child.

Title: Re: Very long pre-calculation...
Post by: zules on 2017-04-21, 14:07:06

Thanks !

I isolated and detached all the stone poly visible from camera and applied displace only on them instead of the whole object.
I also passed the displacement screen size from 2px to 4.

Now the render takes around 3h30 to finish at 2% Noise Level.

Title: Re: Very long pre-calculation...
Post by: maru on 2017-04-22, 19:06:49

The easiest way to check if the issue is related to displacement is disabling it. It can be done in the Common tab using the "displacement" checkbox.
2px displacement size may be overkill for 4k resolution.

Title: Re: Very long pre-calculation...
Post by: zules on 2017-04-24, 17:17:10

Yes that's what I did many times... but even... now it's better !

Also, what px sizes do you think is better for a 4k render ? It's not very clear to me...

Thanks !

Title: Re: Very long pre-calculation...
Post by: maru on 2017-05-08, 13:20:57

Sorry for no replies in a long time...
What was the final result? Did you manage to render this?

If there are still problems with this scene (also in Corona Renderer 1.6), we are interested in inspecting it.

The px size for displacement is really easy - it is simply the allowed size for the smallest detail. No feature of the displaced geometry will be smaller than this value. You should use the highest value which looks acceptable, and also it is a good idea to use bump for the smaller details.

Title: Re: Very long pre-calculation...
Post by: zules on 2017-06-04, 14:11:13

Hi,
I dealed with it by reduce the pixel size & detach faces using displacement from the whole mesh, displacing only the visible ones.