View Full Version : rendering errors

06-08-2003, 04:20 PM
Hi, I'm getting rendering errors in my head model. The model looks fine in modeler but when I rotate the head or camera to get a different shot of the head in layout some of the polys don't render. Turning on double sided in the surface editor solves the problem but why do that, it just bogs down the computer when I want to render.
Any tips are appreciated
JP Westmas

06-08-2003, 06:29 PM
Can you post a screenshot? Could be just a matter of flipping some inward facing Polys.

06-08-2003, 07:00 PM
If this is not a subpatch model, some of the polygons might be non-planar. You need to locate these and triple them.

Alternately, some polygons may have their 'normals' facing the wrong way. Select these and hit 'f' to flip them.

06-08-2003, 10:13 PM
Ironically I modeled my character with the intention of using triangles very sparingly not thinking that quads, outside of subpatching would cause rendering errors. So I trippled my entire model because the errors were everywhere at every shot I took with the camera. Fourtunately the tripling solved the problem but unfourtunately an additional 2,000 polys were added to my character. Can't have everything I guess. Thanks Beam Tracer! What do you think would happen if I modeled in subpatch mode and kept the patch division level down to 1 instead of 2+. I know that patch division at level 1 doesn't divide the polygons at all so: Would the quads still cause rendering errors after I freeze the model? I'm trying to do box modeling here, not sculpt Michaelangelo's David so, Low Poly is what I'm after. Here's an example of what I'm doing. This is after I tripled which works great but it brought me from 3100 polys to 5300. Note: I haven't finished the ears and hair yet.

06-08-2003, 10:24 PM
I wouldn't triple the whole thing. Just maybe certain Polys that are giving you greif.

06-08-2003, 10:37 PM
I found out a neat trick though a bit impractical. If I subpatch my non-patched model with a patch division level of 1 most all the non- planar polys that were giving me trouble became panar and render great without increasing the poly count! The only down side is that the model become compacted and looses mass.:p This means some more surgery will be necessary

06-09-2003, 12:56 AM
If you're going to animate this, all the polys need to be either trianglar or sub-patch polys (but not both).

sub-patch level 1 sub-divides polys once, (into quads when in modeler, or tri's in layout) so sub-patching 1 poly at level 1 effectively totals 4 polys. Level 0 doesn't divide them at all - no good for rendering but doesn't slow down your display as much.

06-09-2003, 09:38 PM
Funny, my subpatch division level doesn't go down to zero and I'm pretty sure level 1 doesn't divide any polys. I know this doesn't make sense but that's what's happening. What version are you using? I'm using mac version 7.5. Thanks for the tip about not using triangles and quads together in subpatch mode.
JP Westmas

06-09-2003, 11:58 PM
You're right, in Modeler it doesn't go down to 0, I should have specified that I was refering to Layout. In Modeler it's only for display, it has no bearing on where it's set in Layout.

To clarify further, if you make your model out of tri's, they don't need to be sub-patch, because a tri can never be non-planar. ( well, almost never )