Scene using way too much RAM when rendering isolated objects in my scene?

[william.morris]

Hello,

I was wondering if you could help me with a RAM issue please?

I am trying to render my animation, which is a house growing up from the ground with all objects flying in from all directions to create the house.

Its a quite a heavy scene theres lots of geometry, proxies, growfx with animated trees and plants, forest pack for grass etc.

The scene is push 28GB of Ram when rendering, which with the amount of geometry is probably right.

The problem is that I dont quite understand is that if i isolate a single object for example a cube and render it on its own, my RAM is still pushing 16GB just to render that cube in isolation.

I have 'render hidden Geometry' off.

I extracted the same cube, camera, lighting and render settings into a different scene and rendered the same image and my RAM only used 1.5GB.

Would this be a problem with my scene?

Thank You Very much,

Kind Regards

Will

[DanSHP]

My thinking would be that, even if you isolate an object to render in a scene, everything else is still there, just masked out. Vray would still need to take into account the hidden objects to produce a correct render.

[Vizioen]

I stopped using Isolate in 3ds max, it's just so very very stupid. http://www.scriptspot.com/3ds-max/sc...olation-levels this scripts does a waaay better job.

- You can isolate in isolate in isolate in isolate in isolate....
- Your view doesn't change when you isolate something (wtf autodesk)
(what it actually does is hide the objects so in your case might be worth to try it, might be better)

[Martin.Minev]

Hi, would it be possible to send us an example scene to support@chaosgroup.com for investigation. You can strip down some of the geometry and the assets, if it reproducible without them.

[william.morris]

Hi Everyone,

Thank You for your comments.

I will certainly check out that plugin, looks really good!

Hi Martin......I will zip up the scene now and email you a link to investigate.

Thank You,

[svetlozar.draganov]

The problem is that I dont quite understand is that if i isolate a single object for example a cube and render it on its own, my RAM is still pushing 16GB just to render that cube in isolation.

I extracted the same cube, camera, lighting and render settings into a different scene and rendered the same image and my RAM only used 1.5GB.

Rendering an isolated object into very complex scene is not the same thing as rendering it in separate scene.
Even though the end result only shows only isolated object 3dsMax still holds all the information into the memory.

Here are the tests I run into our environment as well as the results from them.

1)In Full scene 3dsMax occupies 4.7GBs to load the scene and about 18,8GB when rendering it.
2)In Full scene with isolated object 3dsMax occupies 4.7GBs to load the scene and 13,7GB when rendering it.
3)In separated scene with the same isolated object 3dsMax occupies 1,3GB for scene loading and 2.1 for rendering.
4)In Full scene with all objects deleted except the one selected for the previous two tests 3dsMax occupies 17GB for scene loading and 18GB for rendering.

A few things to notice from those tests. First the memory consumption is less cause I was using the demo version of GrowFX plugin which has some limitation regarding the number of growfx objects.
I will start with the latest test since it's the most interesting one. As you can see in 4) 3dsMax needs about 17GBs only for selecting and removing the objects from the scene and then even though objects are no longer in the scene memory is still occupied.
In test 3) we can see that 3dsMax uses much less memory to load the scene and to render it respectively. In test 2) even though object is isolated 3dsMax still holds the information for the hidden object into the memory and this also affects the rendering stage.

To me this is more related to 3dsMax memory management rather that V-Ray. To confirm that I converted the entire scene to Scanline and I got the exact same behaviour.
The RAM usage wasn't that great since I have removed all V-Ray materials, textures, lights and etc but the memory consumption behavior was identical as with V-Ray.

[william.morris]

Thank you very much for analysing the scene for me.

I think I will break my animation into sections and delete the geomerty etc that is not visible in those sections of the animations to reduce the ram.

[svetlozar.draganov]

Yes, you could split the scene into Xref scenes and enable/disable them when needed.