Verry fast if export's as OBJ in to Blender3d
and use -> Add Modifier -> Decimate -> Option Collapse -> Ratio with verry small value
Import back as OBJ with ImportObj( http://moi.maxsm.net/media/files/ ) from Max Smirnov and add bottle neck and bottom.

@benfarmer
thanks
i would like to have diamond point
i've testesd with boolean diff but my cut are rounded..

@ eddy
thanks but i can't manage the design of the facet

I guess that every rounded-edge would have to have additional facets cut.

Of the 3 ABCarter Rhino tutorials, which use a "cube" to cut, here is one link:
https://www.renderosity.com/mod/forumpro/?thread_id=2647521

- B

thanks but i can't reproduce my bottle example

Do you have a customer model model as template for remodelling ???
Because you previously (first post) spoken of random facets....

in fact , how i can draw facet into a cylindrical model (see attachment picture)
use Trim, other ?

thanks

yes eddy, it's not a pattern (random but design by me) and i want to manage my facets.
thanks

There are some more photos here, including a top view, showing "unsymmetric" shape.
http://www.coroflot.com/cristiano_giuggioli/diamond

Apparently this beautiful bottle design did not win the Agua Carpatica competition (?)
https://www.tumblr.com/search/aqua%20carpatica

The light cast upon the table appears to be the same pattern, for the bottle rotated about 90 degrees.

For a skew quadrilateral, loft of opposite sides can be done, which could make a cutting surface that is not planar...

- Brian

thanks for this link :)
but it's not resolve my problem...pointed facet on cylindrical shape :)

The glass could start as a box, but I think that the pre-faceted blank bottle should be "convex."
At least partly bulged out "conical", rather than cylindrical.
...Sphericalness or Ovalness...

- B

Hi Finema,

maybe you can try the following out:

Save your model as polygon mesh, use a polygon reduction tool, re-import the reduced version,
cut off the top. Create some circles for the top and do a loft twice.

This is my humble approach which i did quickly on a downloaded slim bottle model.

Regards
Stefan

Hi Finema,

> but it's not resolve my problem...pointed facet on cylindrical shape :)

Hmmm, I'm not sure that you're asking for something that's physically possible...

A facet is a planar piece, while the outline you drew earlier on your curved shape was not planar, right? It might be helpful if I had the 3DM file for that rather than just a screenshot.

You can carve off a planar facet from a base solid by creating a plane that intersects the solid and then using boolean difference to slice the solid with a plane. But intersecting your curved surface with a plane will make a rounded intersection with a round object.

Maybe you can describe why you're trying to start with the round object? I think you might be better off working all with faceted construction from the beginning like the examples from others above.

- Michael

Hi Finema, maybe if you want to use your rounded shape as a guide, you could draw a few points on it using Draw curve > more > Point, and then delete it and use the points to draw lines, then form your facets by selecting the lines and running Construct > Planar to build each facet. For a 4 sided boundary that's not planar, use Construct > Network to fill those in.

- Michael

My clumsy model, starting with a revolved ellipse:
For the 1st cut, drew a tangent, used new mirrorsymmetry script, did 6 lofts, moved the 6 faces down a bit, and did Boolean diff.
For 2nd cut, did the same with a different tangent, and a rotate and adjust cut position down a bit.
- B

thanks for all this solution
@ stefan > reduction polygon is really cool but i can't control the facets but i 'll use it
@ michael > draw point on my shape is the great idea because i can control facet. But how i can snap the points on my bottle ?
@bemfarmer > i 'll use your method for an other design
thanks a lot

Hi Finema,

> But how i can snap the points on my bottle ?

Just make sure Object Snap is turned on in the bottom toolbar, and then run the Draw curve > More > Point command and click the "Repeat" checkbox, and click several points on the bottle in the 3D view - "on surface" snap will engage in the 3D view to make the points be on the surface.

If other snaps are getting in your way, open the menu above the object snap button and right click on "on surface" to make that the only active object snap type, and later on after you're done return there and right-click on it again to re-enable all the other ones.

Here's a quick example, I'm just picking points in the 3D view:



- Michael

Thanks a lot Michael

Hi,
How can i force planar drawing point ?
Thanks

Hi Finema,

> How can i force planar drawing point ?

The easiest way is to use one of the ortho views, any of the Top, Front, or Right views (not the 3D view) for drawing any points you want to be planar - when you place points in one of those 2D views it will make all the points after the first one you pick to be on the same plane (oriented to that view) as the starting point.

If you want that to happen on an arbitrary plane then you can set the CPlane first using View > Cplane - once you set a cplane to a custom direction the Top, Front, and Right 2D views will be views relative to that new plane. When you are done with the custom cplane right-click View > Cplane to reset it.

- Michael

Thanks a lot