redraw curve to reduce points
 1  2-21  22-24

Previous
Next
 From:  Michael Gibson
3838.22 In reply to 3838.21 
Hi nos,

> In this case it would be ideal if the control point of the
> offset-curve have a correlation to the source-curve. I don't
> no if this is possible in any case the offset function is used
> but it seams that the ofset curve an be generated by modifying
> the location of the control points.

No, it's not possible to perform an offset just by moving control points around, at least not and make an actual true offset curve that is a constant distance away from the original.

An offset function that only offset control points alone would instead make a curve that sort of generally resembled an offset but would not have the actual "constant distance" relationship.

Your best bet for simplifying the result from Offset is to run Rebuild on it with a tolerance value of something like 0.1 - that should simplify the control point structure of it quite a bit.

But after doing these kinds of various analytic and refitting processes on the curves you won't be maintaining the control point structure of the original curve, these processes work by looking at the geometric shape of the curve (like evaluation points marching along the curve) and not off of its control point structure.

- Michael
  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
Next
 From:  Michael Gibson
3838.23 In reply to 3838.21 
Hi nos, here's a quick example to show you that "control points offset" does not produce an exact offset curve, except in the special case of line segments.

Here I have made a polyline and then produced an offset of it:



Then I drew 2 control point curves (with Draw curve > Freeform > Control points) and snapped on to the end points there, to make these curves:



So you can see there just by eyeballing it that there is not a consistent thickness between the 2 curves.

That's because an offset operation on a line structure is not the same kind of thing as a scaling transformation - applying an offset on just a line structure changes the proportions between the various segments - some segments become longer and some become shorter. Because a line offset produces that kind of changing internal proportions it also follows that just offsetting the control point hull of a curve will also change the internal proportions of the curve.

- Michael

  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged

Previous
 From:  noskule
3838.24 
ah, I see, thanks for pointing that out.

~nos
  Reply Reply More Options
Post Options
Reply as PM Reply as PM
Print Print
Mark as unread Mark as unread
Relationship Relationship
IP Logged
 

Reply to All Reply to All

 

 
 
Show messages:  1  2-21  22-24