View Full Version : Subpatch problems

01-12-2010, 05:44 PM
I am making more and more complex objects for very high resolution prints. I love using sub patching but I am having trouble getting Lightwave to work with them at a high poly count.

Right now I am working on an object that has a little over 4m polys and have sub patch level set to 6. I get an error in rendering that Lightwave could not freeze (or whatever term it uses) the polys and will treat them as polys (kind of cryptic) but shortly after that it always bombs (Lightwave has quit unexpectedly.

I have tried many things to take the burden off it like setting ray recursion to 8, camera to perspective, multithreading to 8 or 16. Anything else I can do to help this along? Right now I am freezing the object in Modeler to make do but that is just a work around.

Forgot to mention I am on a 2.26MHz Intel iMac running 10.6.2 with 4GB RAM. Running Lightwave 9.6

01-12-2010, 06:08 PM
You're running into the 32bit system limit for memory. Reducing polygons is the best way to fix this if you can. Make sure you don't have any polys in the scene that aren't getting rendered anyway, like the backside of the model, for example.

The error means it will not subdivide the subd polygons.

Setting multi-threading higher than 1 per core won't help you unless you're using the classic camera.

Ray recursion of 8 is higher than needed most of the time (unless you have refraction), experiment to find the lowest that you need.
Sign up for the beta to use the 64bit lw.

Just curious, is it 4m polys in modeler or layout, i.e. 4m before or after subdivision?

01-12-2010, 07:57 PM
it's 4m after subdividing in Layout. Deleting polys is not really an option with this object as it's thin and I will be rendering images from different angles.

I am registered for the Beta and tried the first build but it crashed all the time. I guess it's time to give it a try again.

I did freeze the object in modeler for rendering this time but I think I am going to come upon this problem more and more.

Thanks for the ideas!

01-12-2010, 09:45 PM
There must be better threads about the subject, but i think this one could give you a peek on APS and how could you set it up to reduce the polycount after freezing. http://www.spinquad.com/forums/showpost.php?p=257807&postcount=13

Very important to decide if you will go with Catmull or Subpatch first.
since you are using Subpatch going from level 6(6divisions) to, for example, level 3 (3 divisions) might do ok. But if you want to have more steeper changes, you will have to go with Catmull, like in level 3 (8 division) to level 1 (2 divisions).
If you have many objects, it might be a pain to set the APS in each one, but you can always copy the APS Texture layers and paste on other objects.

Good Luck