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Pavlov
03-14-2011, 01:51 PM
Hi,
i'm in a quite troubled deadline and i need some infos urgently about instacing tools in native LW's engine:

- Which HDinstance version is most reliable for LW animation rendering with
pre-saved GI ?
- Is HDinstance reliable and safe on BNR ?
- I'm following DPi development but lately i had not time so i missed most recent developments: did someone try it with pre-saved GI and on BNR ?

thanks a lot !
Paolo

xchrisx
03-15-2011, 09:51 AM
We just used v2.1 on our last project and it rendered fine with LW10 on our BNR Farm. Due to time constraints we couldn't use GI with HDInstance since it was taking way too long for the amount of time we had so I do not know about the presaved GI question you have. Maybe someone else can chime in.

erikals
03-15-2011, 12:18 PM
you can set "local" GI properties in the objects panel, this sometimes does the trick.
depends on the scene /the kind of objects....

Pavlov
03-15-2011, 01:37 PM
hi,
It seems to work.
As Erikal says, local GI makes the deal, but it's the inverse of other situations. In Kray you tell instances have lower GI settings. In LW you must set a very low GI setting in GI panel, so instances will listen to these settings. then you set Local on every other object to set higher GI settings where needed.
With Final Gather GI it seems to be fine and fast. Problem comes if you want to use animated GI, which needs Montecarlo. In this case (even with few small items moving) times becomes totally unacceptable. Do you know some trick to avoid this, (beside compositing animated items)?

thanks,
Paolo

erikals
03-15-2011, 04:06 PM
um,.. no, but the compo is as basic as it gets though...

render the anim,
if areas flicker, use one of these metods.

render anim one time
render anim a second time
mix them in post

or, maybe better, use some of these methods...
http://www.youtube.com/watch?v=-zV7wHlPo38
http://www.youtube.com/watch?v=azsGidV871o
http://www.youtube.com/watch?v=AEb-B_R-JaY

 

arsad
03-15-2011, 04:18 PM
...
With Final Gather GI it seems to be fine and fast. Problem comes if you want to use animated GI, which needs Montecarlo. In this case (even with few small items moving) times becomes totally unacceptable. Do you know some trick to avoid this, (beside compositing animated items)?

thanks,
Paolo

As strange as it sounds I had the opposite case.
I had to do a render of a jeep coming to the camera,
while the camera made a dolly move towards the street.

My first thought: animated object = cached Monte Carlo!!!
But my render flickered as hell and was slow.

So I rendered with FG and to my surprise... no more flicker!
this might have been a exceptional case, but it only worked in
FG.

In this scene there were only 20-30 instanced trees and some bushes.

So you'd better make a fast test if it works on your scene!

Pavlov
03-15-2011, 06:12 PM
Hi all,
xChrisx - tnx for BNR info !
Erikals - comp for noise removal is a nice trick, tnx !
Arsad - well... maybe i miss something but i think that Animated GI in Lw requires Montecarlo... i'd love to use FG ;)
Anyway: i just need some small items to move but GI can be static, i dont need GI to update on walking people. This leads to one question (being a 99% Kray guy, i tend to forget basic things eheh... ): can i use LW's Static GI cache and have items move anyway ? I seem to remember that static GI doesnt allow anything to move... am i wrong ? Cant test now..

thanks,
Paolo

arsad
03-15-2011, 06:24 PM
Well that's basically what I described. A mostly static scene, with a bit of camera movement
and a jeep coming towards the camera and riding by. And it ONLY worked in FG for me!

I used to think it would only work in MC, but on this scene I rendered MC twice,
and it flickered!
I rendered it once again cached with FG and no more flicker.

As I don't have your scene I can't test it either.
So you have to bite the bullet. either test or render in MC and wait till it finishes.

And what do you mean by static GI cache?
When I do a cache I do it for the whole scene.

Exception
03-15-2011, 07:30 PM
It depends on the detail quality you need. You can always try the old motion blur method to provide a variety of passes to smooth out flicker.

But yes, my gamble would be on cached FG with low settings on instances. I just hope your animation isn't too long. Animating objects with the statig Gi cache can also create horrible render time though, in particular cicumstances.

Pavlov
03-15-2011, 07:40 PM
well, maybe i'm missing something so i'll try to be more precise: flickering is NOT the problem in this case.
Problem is about animating items. In LW9.6, "Animation" button in GI panel is ghosted if GI is set to FG. If you click on it, a message says that i MUST set GI to Montecarlo to set Animation ON.
So, reading what you are writing, it seems that i can use FG mode, leave "Animation" button OFF, and items will move in rendering anyway. Is this right ?

thanks,
Paolo

dwburman
03-15-2011, 07:53 PM
The animation cache is designed to let you use interpolated GI in scenes where objects/lights move. It is geared toward keeping the GI samples from flickering, not for an overall speed boost.

erikals
03-15-2011, 08:00 PM
you might try the Locked GI trick,
http://www.youtube.com/watch?v=pGjb3n898pE&playnext=1&list=PL46A206E37B10B876

arsad
03-16-2011, 12:29 AM
Well Pavlor, I'm runnning out of ways to explain myself!

Sorry that I can't be clearer.

I don't now how to put it otherwise, but once again, here we go:

I had a moving object coming to the camera (animated object)
and it worked like a charm with FG while MC did not.
(shadows correct and moving with the animated object and no flickering anywhere)

So animated object plus FG IS POSSIBLE under certain circumstances!

Pavlov
03-16-2011, 08:39 AM
erikals - nice tricks, not just what i need tough.
Arsad... thanks but it's has been always extremely clear ;)
Maybe i'm not explaining but problem is another. I fear there are no more ways to explain this but i'll try to ask more precise questions.
Well. You say you have a moving object in a FG scene, that's ok. Now, what i need to know to solve my issue is: do you have "Animation" button set to ON in your GI panel ? if NOT, which kind of preprocess are you using ? Or even better, can you share a screengrab of your GI panel ?
Then i'll (try to) explain the rest.

thanks,
Paolo

arsad
03-16-2011, 08:55 AM
Hi Pavlov, ok!

Well I couldn't have had the "Animation" button on on while I was in FG, as it is greyed out when in FG. ;)

IIRC my process was to build a cache (Bake Radiosity Scene), lock it when ready (preprocess on "Locked") and then render.

A bit like doing it for MC just with the exception that i couldn't check the animated cache option.

It's been a while since I did this scene 12-15 month ago, but it rested in my mind as it shook a bit on the principles of
animated radiosity I thought I know.

Pavlov
03-16-2011, 09:46 PM
hi,
now it's clear... so, in the end, FG+Locked does the trick.
I'll try it with HDi to see what it comes out, results seems encouraging.
thanks a lot !
Paolo