forrest made of proxy trees, inacceptable light cache duration

[mirciu]

Hi guys.

I have this big scene, an entire street with houses and the camera is set to an aerial view. On the background there must be a forrest, and for that reason o made a small forrest with 3 trees from evermotion ( before multiplying them i turned them into proxies)

It takes like 3 hours just to load the light cache, and that is just for a crappy test render.

 

I tought using proxies would speed up imensely the rendering of large numbers of trees.

What would you have me do ?

 

Thanks.

[Tommy L]

Do not include the forest in the GI calculation.

[mirciu]

OK. in the meantime i found that because the trees were duplicated by using " copy " instead of " instance" , the scene took so long to lgo through light cache. Now that i used only Instance, it load up ok.

My next problem is that, while attempting a medium quality final render, max crashes . I think it has something to do with it running out of RAM, altough i have 8 gb, with Win7 x64 and max x64. It can handle a 640 X 460 or something scene, then when i go up to 960 X 6 something or beyond it crashes right before starting to render ( after doind light cache ) . It ramps overall to 6.4-6.5 gb and then it crashes.

It does the same , no matter if i hide or not the forrest ( which counts for the most poly's in the scene ) .

What advice cand you give me now ? Thanks.

Edited December 9, 2013 by mirciu

[mirciu]

news : i found the culprit ( i hope ) : i also had some cars in the scene, 3 types each multiplied as instance - proxy about 4-5 times ( 12-15 proxy cars in the scene ) . Now it can render happily but without cars ( tried using only 3, same result ) .

 

The scene is bay far my biggest to date and i'm not familiar with the inherent problems of a big scene.

 

It bugs me that max crashes when there is min. 1.5 gb of ram left unused, so i was wondering wether i can change the limit to which max can draw ram .

[radu_ax]

From what I can imagine,if you are using Vray as your rendering engine, the cars you have instanced have a raytrace map on them.

That usually makes the render crash.

 

Check the materials on the instances and delete any raytrace map from any material.

[Krisztian Gulyas]

Windows uses that 1-2gb RAM, so if you have 8gb in total, you can only use 7gb tops.

[RyderSK]

Some evermotion models by default can have very dirty details to them (like trees from 117 I think had displace on parts of meshes..turned on by default, just crazy stuff) like weird material setup (the displacement can be even in material), som old models had raytrace maps like mentioned above,etc.

 

When you turn to scattering, it's worth to check few things: Model (even before turning into Proxy, proxy isn't life saver, it doesn't speed up anything, quite oppositely, it can take longer in most cases, but it saves on ram) is absolutely clean, no modifiers, xRef'ed. Materials are clean, no displacement. You might as well turn of displacement completely in render settings.

 

Enough physical memory (8gb is on the lower end quite some, although people did miracles with 4GB, they used their own prepared models and knew how far they can get, not premade stuff that isn't crated with much optimalization in mind) and since we're talking vray, also enough Dynamic memory set in settings.

 

Though concerning those cars...too many of them might crash whatsoever, too much geo and materials that nothing will save. Use low poly (and ideally single mat, low res textures) for scattering and few unique "hero" models for close-up.