3d displacment crash

[teabag]

Hello,
I know this has been around many times, but i have a problem with 3d displacementin my scene. The object topology that i am trying to render is ALL QUADS, the texture i am using as a displacement map is about 1400x1000 pixels (i know its kinda big but i cannot use aynthing else). The image size i am rendering is 2000x1000 pixels. 3d displacemnt edge legth is 2pixels, keep continuiry on.

LC and IRRAD map render fine. Render crashes about half way through the rendering, i guess its its runnig outta ram (have dual core, 4 gigs ram, xp64, max9x64, vrayRC3 64)...

I know u r probably going to tel me to use 2d displacement or check the dynamic memory - by the way it never really helped - i always ended up redering the 3d displacment either with the help of regions or as a separate object in parts.

What i am curious about this time is.....would rendering to vrayimg help?
The one thing i am curious about has this runnig out of ram issue been fixed in future builds? If not whats this feature usefull for if it canno be really used in bigger extent? As i see it, in larger renders (or when 3d displacement is more used) it is absolutely useless!!!!

Do u guys have any other suggestions how i shoud setup the render so i dont have to PS it? i really would like to use this great feature, but somehow i havent been lucky enough to do so because of above reasons...

I have seen some great renders (large scale ) with a massive use of 3d displacement on this site, so there must be something to make it work.....could anyone be please so kind and tell me the secret? ))))

thank u guys for any reply

best regards

Martin

[teabag]

the weird thing is that it will compute both GI bounces (LC and IRRAD) and it crashes at render.
I assumed that if i saved the LC and Irrad calcs into the file and use it later on will sot out the problem , but the render crashes anyway....

when is 3d displacement finished computing anyway? along with GI computation or while rendering? If it is finished when both GI bounces r done why doesnt it simply save the displacement?

or why doesnt it swap the displacement on the disk? to free some amount of memory?

I just cannot believe that with such a small resolution it is capable of eating 4 gigs of ram!?

Vlado:
please can u give me some insight on how the 3d displacement is being computed and what steps can be taken in dealing with the lack of memory issues? (as adding another 4gb can be quite costly)

[Morbid Angel]

I dont think the displacement is to blame here. We render large displacement maps 4k often without problems. However having said that, there is a reasonable limit to which you should stick to.
I think an image to demonstrate your problem will help.
Usually displacement will fail in memory if there is way too many subdivisions. Or, if there is too many rays to trace for an extremely heavy mesh.
Thats all I can say right now, without a visual aid.

[DaForce]

Looking at your file now mate. Hopefully will get back to you soon with something usefull

[DaForce]

Well I dont really know what to say other than I opened it and it rendered fine first go without changing anything.

Never went over 1.2gb mem usage.
I am however using a version more recent than rc3.

I will try with RC3 later.

[teabag]

thanks very much daforce ..... i thought that the rc3 version might be the problem with the displacement ((( ive been in touch with a friend of mine whos using RC3 as well and he cant seem to get his projects with displacement working properly.......ive read so much about using displacment and u personally gave me so many hints how to use it....i think i am not doing anthing wrong this time.....

morbid angel:
here is the screen grab of the mesh i am trying to render....ive sent a link to the rapidshare where u can download the scene if u want to have a look



this is a group of objects which one by one r all quads editable polys.....one thing that comes to me now is....what i did is i had these editable poly objects, grouped them, applied UVW map on the group and applied displacemnt on the group as well....should not i do it on each object separately?

cheers

[DaForce]

Im curious tho, when yours crashes, how much memory is in uses?
Also you could try 2d as your just displacing flat surfaces so might well work fine.

However it did render fine in my system and I only have 2 gb of ram but i am using a newer RC as I mentioned.

But check the memory usage on yours when it crashes. Are you using 64bit by the way?

[teabag]

yep all is 64bit...

when viewing windows task manager i can see that at computing LC,
max itself uses 2.232 Gigs
PF usage is 2.96 Gig
Available mem 726 megs
commit charge is 3.045

in max render window it says the mem used is 2.18 gigs


which, when i consider what u said daforce, means that there r huge diferencis in memory consumption in releases above RC3...or what else could it be?

[teabag]

not sure how mouch mem it uses when it crashes though

[DaForce]

well it seems like its using the same amount of mem as mine. as your max is only using 2.2 pretty much what mine used.

weird. well certainly RC* is an improvment over RC3.

Just popping out for dinner with my GF, will run a RC3 render while im out of your scene and see what happens.

[teabag]

alright mate thanks for your time and effort!!!!!

[teabag]

i am not the only one who has problems with 3d displacement with rc3 version, couple of vray users i know have the same issues as i do.

I just wish vray final or at least new stable build would be available for the users very soon....shame its not available for all the registered users to at least try the newer builds...it just would make things mu much easier sometimes

[DaForce]

Well mate, this is going to blow your mind. But it appears to be working just fine with RC3 as well.

its past half way and just moving up past the right hand side of the building.

Im pretty sure it will work.

I am however running 32bit. So if it renders there must be some weird difference between 32 and 64 or something is borked in your PC

[teabag]

shit...will have to give it a go on my other machine then....

[DaForce]

yep I can confirm it JUST finished rendering on RC3.

used about the same mem as RC*

So yeah.. somethings fishy with your install me thinks.