Why is the LC Building so different?

[dynaman]

you mentioned that you had animated visibility? i just noticed on a current project that when i set the visibility to less than 1 for a certain group, the light cache calc went from less than a minute to...well, i killed it after about 5 minutes and no progress.
how many objects in your scene have visibility set to less than 1? i found that for every object with visibility less than 1, the light cache would slow down at an exponential rate. my solution was to decide not to make the objects transparent.
i suppose you could animate their material opacity - don't know if this would have the same effect on calculation time though. depending on the effect you're going for, you might also try using an environmental fog.

[Dynedain]

you mentioned that you had animated visibility? i just noticed on a current project that when i set the visibility to less than 1 for a certain group, the light cache calc went from less than a minute to...well, i killed it after about 5 minutes and no progress.
how many objects in your scene have visibility set to less than 1? i found that for every object with visibility less than 1, the light cache would slow down at an exponential rate. my solution was to decide not to make the objects transparent.

This is true for scanline as well, not just VRay. I believe it's because using the visibility track means that the rendering engine has to calculate every operation on the object twice, once for the object there, and once for the object not there, and then blend the results to the visibility value.

[SnipeyX]

I've had several projects where I've tried to implement fading things away via visibility track, and I've never been able to really get it working properly other than with QMC.

If others have tips on animating objects fading in vray (other than in post) please share!

[Buck]

you have to have the object snap on and off (from one frame to the next, not multiple frames), no fading, fading seems to slow everything down horribly.

[SnipeyX]

unfortunately instant disappearing is not always what the client wants.

[Syclone1]

Im with Buck, we have a lot of videos here that need objects to fade in and out and the best way Ive found to do that is either have the object go from invisible to visible in one frame and make the fade in post or if there is movement then I find its often faster to render 2 passes and again create the fade in post and you have alot more controll over the fade in this way...

-dave

[jujubee]

I had the same problem here as well as several other scenes. Check this post as I was testing and think I found a temporary solution:

http://www.chaosgroup.com/forum/phpB...ic.php?t=16772

[k-arts]

Thx

Thx Guys ! Your help and thought are greatly appriciated! Luv goes out to the Vray Gang.

It does seem so that the visibility spinner is the reason for my troubles. I am rendering now a different object but having also an animated spinner. I am using a dome light made up by 26 spot lights so no LC or QMC and ofcourse no GI. And it does almost come to a halt when rendering the geometry with the anomated visibility. So my advice as you guys seem to know is DO NOT ANIMATED THE VISIBILITY SPINNER ITS EVIL

I give it some different approach now but will keep u guys posted


thx guya


ralf

[DaForce]

Animating the visibility spinner has always been a big NO NO for vray.

[k-arts]

Short follow up

Funny however it seems that when i set the refl. glossiness to 1 instead of 0.86 it seems to render just fine. Funny thing this stuff


well hopefully i get to go to bed soon

ralf

[k-arts]

darn problem reapeared...

Ok the problem is back. Noe the Refl. Glossiness set to 1 and no visibility spinner animated, however after 10 frames into the animation the lightcache build up jumps to 7 hours and still counting. Now i am thinking since we mainly use geometry imported from an dwg cat file it has something to do with that. Like bad faces layerd over each other. Does anyone else have encounterd problems with that ?


thx for any advice

ralf

[DanielBrew]

Yes, I've duplicated objects over the top of each other and rendertimes do shoot up .

Don't know why it only affects certain frames in your animation though.

Dan

[DaForce]

try turning LC preview off.. and see if that helps.

[k-arts]

Lc

Thx, but i havent even turned on the preview. I now fixed a few geometries and created a domelight made out of 40 spotlights and did some tweaking at the end. So a frame takes now 10 minutes to render. Interesting though would be what causes all this trouble.

well

i get back to you as soon as i find out


ralf