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
