This is not a direct answer, but what you have there is a 'Celtic Knot'. There are ways of getting this done for you ;-) http://www.abbott.demon.co.uk/knots.html

No doubt Pilou will like this one. :-)

Hi Reiner, sorry I think I misunderstood your question, I thought you were finished with the knotwork part and were working on filling in the middle part.

For getting the over/under knot part, you would indeed need to turn points on (inserting some where necessary) and pull these up in z.

For such a long intricate sweep I think you are probably better off doing all of that before doing the sweep, rather than doing the sweep first and having it update in response to your pulling - like you mention such a long sweep will be rather slow to recalculate.

- Michael

@Lemo ;)
As the motif is very symmetric just make the minimum and mirroring maximum ;)
That can reduce a lot of time and take the manipulation more easy!

Hi guys,

sorry for my late answer, but i tried most time of last night to get a result with zsurf, but it was not satisfying.

@manz: wow ! How can you do this in such a short time ? You can give me the 3dm file ? No, just kidding... i have tried it for hours but i have to do some more practice....

I must work the hole day ( now lunchbreak ) so i soonest can get back to this thread tomorrow.

Thanks for your ideas,

Reiner

Steve, as Reiner suggested--
just how did you do that in such a short time, ----please!

Hi Reiner, can you post a .3dm file of what you currently have?

That would make it easier to give you some help.

Like Pilou mentions, it looks like one step is to focus on just one quarter of the design and then use mirroring to build the other parts.


> but i tried most time of last night to get a result with
> zsurf, but it was not satisfying.

Sorry about that, I thought you were asking about doing the central bubbly part, that's the part that zsurf could work well for, not for the knot work in this case.

- Michael

Hi Brian,

>>>just how did you do that in such a short time

I just created as already mentioned, which was, I loaded the picture of the frame, then I followed (traced) the path of the frame (piping) using the "free form~ through points" and placed a point at each intersection (where the pipes cross over) I did that first for the first path:-



I then added any needed points to correct the shape (keeping points to a minimal), then I selected all the points where the pipe moved behind (at the intersections) and moved them using align.
I then repeated for the other 3 paths.

- Steve

Hi guys,

i see, other people are also interested, so i share what i have...

This is where i started, i have other, but not woth to look at ;-)

greets,

Reiner

Thanks Steve and Reiner.

Hi Reiner, to start with I'd focus on slicing it down to just work on one quarter of it.

To do that, you can draw in a rectangle like this:



Select all your knot curves, then run Edit/Trim, then select the rectangle as the cutting object. Then select the pieces to remove - actually in this case I switched the Mode to "Keep" and selected the pieces inside the box to keep.

That will create this result:



Now you can focus on editing this corner of the knotwork and later on mirror the results to create the full pattern.

However, it is still going to take quite a lot of fine tuning and adjustment of control points to get the final result that you want, there isn't any easy way that I know of to automate a kind of weaving pattern, you will have to manipulate control points of curves up and down in the z direction to do it.

You may want to get the Nudge command set up on your version from here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=952.11
So that you can set up your PageUp/PageDown keys to move a point up or down a bit in the z axis instead of doing mouse manipulation for each one. Let me know if you need help setting that up.

You'll also probably need to add control points in at some strategic locations to manage the effect of dragging a point. if you have too few points in an area, then dragging one point will like pull up too large a portion of the curve. You can insert more points to localize the displacement to a smaller area of the curve.

To do this you may want to use the "insert knot" variant of Add point - this is a method of adding a point to a curve without changing the shape of a curve. This method is used if you use Add Pt and click on a curve at a point without control points turned on for that curve. This method adds a point in that general area and shifts the location of other control points slightly - when you insert a point when control points are on and click on the hull segment in between 2 points, that does a different style of point insert where all the points stay in their place and instead it is the shape of the curve that can shift slightly.

This is definitely a difficult task, I hope some of the above information will help, please let me know if you need any more details over any particular part.

- Michael

Reiner, I sent you a PM reply.
Let me know if you did not get it.
Brian

Here, firstly, is a very rough work on your original image to simplify it to the basic knotted frame image.
The second image, in Carrara, shows, on the left, a straight "print" and, on the right, when I have used the displacement tag in the shader tree.