MS, grass, and NOT LC

[Crayox13]

Hi,
So I finally did some tests. I spread my grass (small bushes of grass, each 4000 faces) on a 2000x2000 plane. In MS I put max count to 500 000. Again I started to receive "unloading geometry" so I wrote to MS support. Just got their answer. They said not to use LC. Hm. Okey. But IR+LC is the fastest and best method ever, I use it for everything. Will play with BF now a bit, but it's so slow. Any ideas Vlado? This is normal for LC to get stuck on many instances?

[Crayox13]

Ok, tried IR+BF method. For this scene that is attached, it took 5 hours and 2 minutes to render when I turned off generate GI for the all grass objects, and 6 hours and 22 minutes with GI calculating everything. Is this normal? I still got unloading geometry.

[vlado]

It is somewhat normal. What is the value for the "dynamic memory limit" option? If it is too low and the geometry cache overflows, you will get this message often regardless of the GI method.

Best regards,
Vlado

[Crayox13]

4000MB, and I have 8GB of RAM. But how come unloading geometry takes so long?

[vlado]

You can try setting it even higher (e.g. 6000 or 7000 MB). It might not take so long, but simply happen very often.

Best regards,
Vlado

[Crayox13]

Yes, setting limit to 7000MB made much better usage, and it didn't start unloading cashe when I was at my computer, so like almost half of LC was ok. I left it over night. Today when I opened it, it said it was rendering for 6 hours and 1 minute. Hm, I don't get it, the estimate was 1 hour for the LC, so then IR should of been fast. Is there any way I can see details on how long was the LC, IR, and then the final render?

I mean that was longer than IR+BF.

[vlado]

You can see the time for the various stages in the V-Ray log file (its name is specified in the System tab in the Render Setup dialog).

Best regards,
Vlado

[Crayox13]

Thanks.

So I got a reply from those guys that made MS. They told me to give them the scene, my vray version, OS, etc. This is their reply:

hello
looks like you need to learn more about how to use V-Ray
the rendering setting in you scene are incredibly inefficient

e.g. inappropriate use of light cache and adaptive subdivision lead to huge memory consumption

regards
Anvar

Is witchcraft involved to change those few settings? Do I have to be a member of the mason society or something? Or should the settings be revealed to me under the blue moon? lol sorry, couldn't help myself. Ok, my settings are wrong, but what kind of a tech reply is that? I DID pay for the software, and ok, they don't sell vray, but still.

Anyway....sorry for the digression, but I know for a fact that at least one more user here bought MS and couldn't use it in his production, so is there anyway we investigate this problem further? Vlado, do you guys have MS so you can test my scene, or should I just post my settings?

[Neilg]

Just post your settings, if they're as off as he says then it should be obvious to people without multiscatter. Even people with it cant really help much without knowing what you've already done.

[PIXELBOX_SRO]

i reckon you might have really small LC sample aadn possibly high count of subdivs.....try to optimize them....start with smaple size 0.02 and LC subdivs around 1500 for A4 size render.....see what timing you get??
or post your settings that would be easiest

[Crayox13]

LOL, I have 1000 subdivs, and everything else default, so 0.02 sample size. I think they don't know what they are saying. Only thing is that I increased dynamic limit to 7000MB, tomorrow I'll try with low, like 1000, although I think that'll make it worse.

[peprgb]

For what i have read, with huge amount of proxys is not recommended LC here because of RAM needs

Here they recommend not using LC too......?¿

I'll check out this thread for confirming...

[Crayox13]

That's what they said first, "don't use LC". Then I wanted more info on all of this, and at the same time tried IR+BF, I posted what I've got. Also pretty high RAM usage and 6 hours of rendering for 500 000 max objects (grass units) on a simple plane 2000x2000.
The more info is what I posted here in red letters

Thanks for those links, I'll check them out when I get home.

[Crayox13]

First, here are the screens of my settings. So how come my render times, and behaviour is so different than of PIXELs?

On the second note, it WAS silly of me to leave LC on 1000, I got similar looking scene with LC subdivs on 100. Will now test it even without the secondary bounces. These are all then methods for rendering grass separately.

[Neilg]

I'd never use LC for an area like that (internal only for me) but i cant really see anything in the settings posted to see why it's taking so long. I wouldnt expect that to take any longer than 20 minutes.

You also missed out a load of your settings.
make sure your grass materials all have a max depth of 1
turn off bitmap filtering for anything with opacity
use adaptive dmc - 1,8
Ir map medium preset, 60, 30
brute force subdivisions 8 and secondary 4
and drop your render region division to 32.

Check the materials for glossy effects too. turn glossy refraction off, if it's on. Reflection just increase a bit (say if it's .8, raise to .9)


Also it might help if you post your specs. If you're rendering on a p3, this might all be explained easily...