PDA

View Full Version : Preparing geometry for subdivision


Kien
11-11-2009, 11:18 PM
In order to keep a fairly hard shape on objects the mesh must be prepared with extra beveling and such. I have 2 questions.

First
When it comes to beveling. Is it a general thing to avoid beveling edges with knots on them (5+ edges meeting), and therefore insetting some edges to fix the area around the edges that are to be beveled? See the picture in the link.

http://img39.imageshack.us/img39/6072/edgebevel01.png

As you see on the picture it's a box that is supposed to have some square polygons in the middle of the side and also have beveled edges. The unprepared mesh gives a weird edge since it chamfered a knot. The last mesh in the picture is after it has been beveled when it was prepared for it by adding a line for the knot before the edge that was to be beveled.

Is this something people in general take care of? Like making sure there are no knots on the edges to bevel.


Second
Here are 2 ways to keep the shape of a mesh and prepare it for beveling. The difference is the topology. The shape of the mesh is the same. It's just the cutting at the corners that are different (in general). As you see the green version keeps it's shapes much better when subdivided. Is the green version always the prefered ones? See picture in the link.

http://img44.imageshack.us/img44/1636/highpolypreparation01.png

The difference is that the blue has got it's polygons extruded with no length but with offset ( in max it's called inset ), and on the green version it simply has cuts that goes all along the edges in a straight lines.

Here is a picture of how it turned out when the edges where beveled/chamfered with 2 lines/divisions/levels.

http://img29.imageshack.us/img29/984/highpolypreparation03.png (http://img69.imageshack.us/img69/3143/highpolypreparation02.png)


Is the green awlays the way to go?

Piflik
11-12-2009, 08:17 PM
I don't use Chamfer to prepare edges, since it destroys the original one and I have a hard time if I want to change someting later. I use Connect or Extrude to add edges and then move them to the proper position with activated Edge Constraint.

And yes...it is always the green way...

Kien
11-13-2009, 12:05 AM
I don't use Chamfer to prepare edges, since it destroys the original one and I have a hard time if I want to change someting later.
People always tell me that chamfering is something obvious (and they never heard of creasing) because no real life edges are truly hard anyway (...yeah in microscope level). I myself disslike chamfering edges. I think I like the method I used in the pictures by letting the edges be and just adding more lines next to them.

CGTalk Moderation
11-13-2009, 12:05 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.