how to convert a polygon with curved vertices to an approximated "lines only" polygon?

[relume]

 

Hello

 

For external geometrical processing in a python script, every VW polygon that has one or more curved vertices has to be converted to an approximated "lines only" polygon. This represents the standard transformation for any curved vortex on exporting VW objects by the export function to the Shape-Geodata format. There is also an VW-menu functionality, that converts a polygon to a multi-line group, where curved vertices were approximated by as many needed short lines.

 

At the moment I can not see, how I can get/convert to such a "lines only" polygon by a VS function. The idea is the following:

 

1. get the handle of the VW polygon.
2. test if there is one or more curved vertices by looping through all vertices of the polygon (using vs.GetPolylineVertex).
3. if there is any curved vertex in the referenced polygon, make a temporal copy of the original polygon and convert this copy to a "lines only" polygon.
4. process the "lines only" polygon as needed in the python script

 

Step 3. is the operation  I am interessted in – a "fast" and VW internal converting operation to a "lines only" polygon or a group of lines.

 

Many thanks in advance for any hint, best regards,

 

relume

[MullinRJ]

@relume ,

Use:

def  vs.ConvertToPolygon(h, resolution):

   return HANDLE

 

Setting integer "resolution" higher creates more vertices.

 

Notes:

1) This function creates a duplicate object, so you don't have to duplicate it beforehand.

2) If the original is selected, the duplicate will be selected, and vice versa.

3) Magic numbers for the resolution are powers of 2.

 

Raymond

Edited March 3, 2020 by MullinRJ

[relume]

@MullinRJ

 

Many thanks four your hint! It seems that I did not seek the VS functions in deep 🙄.  The vs.ConvertToPolygon(h, resolution) is perfect.

 

relume

[MullinRJ]

You're welcome. I like the easy answers. You get full credit, just for using your memory. 😉

 

Raymond