PDA

View Full Version : Subdivision order sluggishness?



WShawn
02-23-2009, 12:26 PM
Hi:

I'm working on a scene with basically one object, three layers. Some parts are subdivision objects, Catmull-Clark. Around 43,000 total polygons. I have the display SubPatch Level set to 1 on all objects.

I have a few bones on one Sub-D element to make it flex. I found that if I set the Subdivision Order to anything but "First" my time slider/scubbing responsiveness tanks, even if I set my one window to Bounding Box mode. If I set the Sub-D order to "First" I can play my simple scene in real time and get almost all 30 frames per second. If I set it to anything later than "First" I only get around every 7th frame.

There's a thread in the LW 9.5 Open Beta section that touched on this issue. Was it ever resolved? I'm working with LW 9.6 Release Candidate 12 (Mac 32) on an 8 core Mac Pro using the stock ATI Radeon HD 2600 card. This version has been working fine for me, so I haven't felt an urgent need to upgrade to the final final current release.

Thanks.

Shawn Marshall
Marshall Arts Motion Graphics

Nicolas Jordan
02-23-2009, 01:42 PM
Have you tried using regular Subpatch surfaces to see if it's any faster?

WShawn
02-25-2009, 02:31 AM
Objects using regular subpatch geometry don't slow down the responsiveness when the subdivision order is set to something later than First. So it looks like CC sub-D objects are the problem.

It's not the raw poly count. A CC object set to a display subpatch level of 1 with 4800 polys will slow the preview down if set to something other than First. A regular sub-D object with a display subpatch of 4 with 19000 polys displays smooth responsiveness when set to Last.

If I set the display subpatch level to 0 on the CC object the preview remains smooth, but that kind of defeats the point.

I tried the same test with a simple box but couldn't duplicate the problem. Maybe there's something weird about my model, though what it is, I don't know.

Thanks.

Shawn Marshall
Marshall Arts Motion Graphics

Jure
02-25-2009, 09:27 AM
I have same problem here. It looks like a bug!