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Author Topic: extremely slow rendering when fp NOT excluded from photometric lights!!!!  (Read 2460 times)

Morpheus

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Hello.

I am using 3ds max 2012 with the latest forest pack version.
I use MR as rendering engine.

My project is a 2000x2000 resolution using FG, GI, MRexposure control.
I also use daylight system with Mr sun and skylight (not Mr sky) with an HDRI map
assigned to it (and as enviroment backgound of course).

When I render it only with the model and the maps everything is ok.
When I put inside many forest pack trees, flowers ecc, the rendering
becomes very very slow.

I assign to each forest pack object the Mr sun as shadow and converted
all the materials to forest material, but the rendering time are kept very slow...

Any solution how to render faster?
thank you.
« Last Edit: June 04, 2013, 01:06:47 PM by Peter1971 »

iToo

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Re: extremely slow when using hdri skylight
« Reply #1 on: June 01, 2013, 02:32:30 PM »

Do you use 3D objects or billboards ? The operation mode of Mental Ray is very different in each case.

Carlos Quintero
iToo Software

Morpheus

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Re: extremely slow when using hdri skylight
« Reply #2 on: June 01, 2013, 02:59:56 PM »
billboards

I don't have absolutely any problem of the rendering quality result with forest packs.
The only problem is that requires dozens of hours rendering time.
Instead without fp, only in less than an hour is finished....

I think it has something to do with the Hdri skylight.
Instead with Mr Sky I think it's faster...
« Last Edit: June 01, 2013, 03:03:28 PM by Peter1971 »

iToo

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Re: extremely slow when using hdri skylight
« Reply #3 on: June 01, 2013, 03:42:52 PM »
Ok. I'm out of the office now, but i will make some tests later. It's not normal those render times using billboards.
Carlos Quintero
iToo Software

Morpheus

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Re: extremely slow when using hdri skylight
« Reply #4 on: June 01, 2013, 03:57:57 PM »
ok...

I can send you also the project if you want.
But the truth is that since now I didn't have major problems
with the rendering times (my model+forest pack).
Max 2-3 hours for a high res rendering.

My last two projects that I used skylight with an hdri sky map,
the rendering time is exploded.
And I have to reduce other mr factors (resolution, image precision ecc)
to archive a worse result but in less hours... :(


iToo

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Re: extremely slow when using hdri skylight
« Reply #5 on: June 02, 2013, 11:08:04 AM »

Yes, please send us the scene. I can't reproduce the problem here, but probably i'm not using the same configuration.

Carlos Quintero
iToo Software

Morpheus

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Re: extremely slow when using hdri skylight
« Reply #6 on: June 03, 2013, 03:31:07 PM »
Carlos I just sent you a link to download my project.
I called it "fp-slow"

Please render it as is.
In my pc with all textures+some additional models of windows/doors/objects
it takes about 20h to render it.
I have a  HP XW6400 workstation with 64bit 3ds max 2012 (4gram and 2x2core xeons)

Is it normal?
Please I wait your answer.
thank you.

iToo

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Re: extremely slow when using hdri skylight
« Reply #7 on: June 03, 2013, 04:56:40 PM »
Thanks, i got the file. But it renders pretty fast here: less than 2 minutes (i7 980x 3.8 Ghz, 12 Gb. RAM). I used the default settings included with the scene.

There are a couple of missing files: a referenced dwg (koyka18.dwg) and the plugin scalpel64.dlm. I don't know if that would be a difference.

Also i see the trees at the background use Forest Material, but there are not Base Materials assigned, so they render black. I attach a screenshot with the final image and render time.

Carlos Quintero
iToo Software

Morpheus

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Re: extremely slow when using hdri skylight
« Reply #8 on: June 04, 2013, 01:05:37 PM »
Thank you for the reply and the rendering test.

It wasn't the skylight/hdri the enemy... :)
Finally I have found what was the problem.
I will share my discover here because these forums and in general
all 3d forums are the biggest help and the greatest school for us
that we are spending tons of hour behind a computer...

So after that you rendered the image in such a quick time I discovered
that the problem was with the lights!!!!!!!!

The scene I sent you -except the Mrsun- has no lights inside the house.
If you create for ex. 15 photometric lights inside this house and render again,
you will see that the render is very slow.

So what I did?
I excluded all the Forest Pack objects from the lights and voila'!
The render has become a lot faster....
« Last Edit: June 04, 2013, 01:07:50 PM by Peter1971 »

iToo

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Thanks for letting us know. I'm glad the problem is solved.

Carlos Quintero
iToo Software