How to close organic surface?

Hi, I have this kind of surface and trying to close it organically?

The quickest way is to patch it. It gives you G1 (tangent) continuity which is enough in most cases.

More advanced… To get a G2 (curvature continuity) you may need to trim the object a little to make place for a nice rectangular surface, created with _NetworkSrf. Here is an example where I pulled a rectangular curve onto surface, than used it to trim the surface. I adjusted the surface seam, and blended extracted isocurves to get some support geometry (curves which let you control the shape if history is enabled).

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Hi Alexey - can you post the surface?


Untitled.3dm (338.2 KB)
Here is the file

The bad thing about patch - it have not enough accurate outline. It’s mean I have a gap some places between main surface and patch. About surface from curves - it’s not easy to understand, how to quadrate the hole. I have ellipse as a shape…

Untitled.3dm (5.1 MB)

slightly deformed but closed, if this can help you. first use ShrinkTrimmedSrfToEdge then switch on points and choose the most outer row of points towards the hole and use SetPt with x, y, z turned on and locate the point where it becomes most natural. you can also use AreaCentroid to get a center which you move outwards and use as a set point focus. you can also extend the surface first to keep it more like the original shape but you have quite a kink in there which quickly leads to a selfintersecting surface, maybe rebuild it accordingly if the shape is not needed like that 100%

That is really close and amazing. But result is about different from what I’m looking for. It’s my bad, I should show and example. The shape I’m trying to recreate.

There is the part between earphone and cable which is looks like sea stone. I’m building only this part. So, the both side should be smooth from both sides. In example with dots its a bit sharp.

I need some tools like Editable patch in Max. Where I can divide surface to segments and move dots with curvature control by some bezier. I know that is no bezier in Rhino. But is there any chance to create flat square and change it with no age deformation?

Create the square surface.
Rebuild as Degree 3 with 4 or more points in each direction.
PointsOn to turn on control points.
Move, MoveUVN, or drag interior control points to change shape as desired.

Useless. When I do so, I’m loosing edge control… It’s not match previous form any more.

Is it possible to FIX or LOCK the edges to keep them in the same position and the same shape to change then the rest of the surface?

[quote=“Alexey_Borisov, post:12, topic:42135, full:true”]
Is it possible to FIX or LOCK the edges to keep them in the same position and the same shape to change then the rest of the surface?
[/quote]If the surface is not trimmed then the position of the edges will not be altered as long as the control points along the edges are not changed.

If the surface is trimmed there is no simple method to keep from altering the trimmed edge when changing the shape of the surface. Patch produces trimmed surfaces if the “Automatic trim” option is selected.

I don’t see why you can’t use a solid sphere, and modify it to get a clean shape with no bumps and extra points.

  1. Make sphere roughly the size of the earpiece.
  2. Rebuild it with 8 points on U, and 8 points on V.
  3. Run _MakePeriodic to soften the seam.
  4. Scale it on X, Y, and Z into shape, scale and move the rows. Use _SelU and _SelV commands.

You’ll get a much cleaner and manageable surface this way, which you can split by isocurve later, and blend with the other sphere.

It’s about the same workflow you would use in 3dsMax if you are familiar with it.