Weird non-manifolds with polygon pen

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

 
Thread Tools Display Modes
  06 June 2018
Weird non-manifolds with polygon pen

Hello, all. I hope, you can help me with this. 

Iīve never modeled with the mesh check enabled but because of a job modeling a house for use in Unreal Engine, Iīve decided to set in on. Bad decision... very bad, because of this ...um... bug (?) is driving me crazy. Is it a bug or just me?!?

 This is a simple wall, made from a converted cube with cutted edges for the doors and windows. To make a wall integrated balcony, deleted the frontside polygons. Before Iīve extruded I closed the hole between front and backside with the poygon pen (auto weld on and also tried it after the extrude). But then... here they are. non-manifold red lines... 

Iīve checked anything after hidden polygons or not connected points... and found this: the backside connection has two edges but also only two points... Shouldnīt it be four points in case of not connected poylgons or one edge in case of nicely connected polygons in love... without any red flagged non-manifold geometries?!?

See images.  

1: No hidden geometry




2: Here we are.





3: One edge at the frontside (Yeah!!!)




4. Backside two edges





5. But only one point here...




6. ...and one lonely point there.






I very appreciate your help. 

thanks in advance
 
  06 June 2018
when you are selecting stuff trying to figure this out do you have "only select visible..." unchecked? If 2 points/polys/edges are in the same place, only one will be selected if "only select visible" is checked

and have you also selected all the polys and chosen "optimize"?

and also, have you selected all of the polys and checked which way the normals are facing?
 
  06 June 2018
Originally Posted by mikeh64: when you are selecting stuff trying to figure this out do you have "only select visible..." unchecked? If 2 points/polys/edges are in the same place, only one will be selected if "only select visible" is checked

and have you also selected all the polys and chosen "optimize"?

and also, have you selected all of the polys and checked which way the normals are facing?

1. Yep
2. also yep
3. yep too 


I think Iīve tried all possible variants to exclude any user-failure...  but you never know. 
 
  06 June 2018
Maybe I'm way off base, but, an easier method would be to extrude the wall with
a spline built in c4d (Ai,etc).

Here's a simple example:


__________________
David

iMac 3.06 ghz Intel Core 2 Duo / 16 GB / OS 10.13.4 / C4D StudioR12 / CS6
 
  06 June 2018
Non-Manifold means an edge is being shared by more than one polygon.
In general you want to avoid them, if you delete the single sided poly filling the window, they will return to nominal edges.

If you want a one-poly thick window area, I would disconnect those polys or split it from that mesh completely

cheers,
brasc
__________________
brasco on vimeo
 
  06 June 2018
Originally Posted by vid2k2: Maybe I'm way off base, but, an easier method would be to extrude the wall with
a spline built in c4d (Ai,etc).

Here's a simple example:




Thankīs for this tip, David. Thatīs a good allternative but unfortunatelly in this case not. .-) Because of two reasons. One is that itīs a little bit more work when you model a building after a given architectural floorplan. The second is, this method makes unwanted slices from corner to corner like the boolean method. I did not have good experiences with that for working in Unreal Engine.
 
 
 
  06 June 2018
Originally Posted by brasco: Non-Manifold means an edge is being shared by more than one polygon.
In general you want to avoid them, if you delete the single sided poly filling the window, they will return to nominal edges.

If you want a one-poly thick window area, I would disconnect those polys or split it from that mesh completely

cheers,
brasc
Hi, brasc. Thanks for your that. That explained a lot for me.  There are three polygons sharing one edge.Thatīs my problem with the balcony and at the doors area.. I will split the balcony from the wall. But itīs not necessary for the window areas. There are no non-manifolds. See here:




Again thanks a lot for that. Now I can sleep again .-)
 
reply share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright Đ2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 08:31 AM.


Powered by vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.