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Hello,

 

I need to rebuild polygons from points, but need certain vertices' criteria.

  1. Polygons need to be digitised in a clockwise direction (can use orientor transformer for this)
  2. Polygons need to start with a vertices which has highest z value.

How do i define the start vertice for the polygon when rebuilding the polygon?

Capture 

Thanks

@Takashi Iijima​ @david_r​ @Hans van der Maarel​ @ebygomm​ 

I haven't tried this at all, but what if you:

connected the vertices into a line (polygon perimeter)

used a coordinateExtractor to get the list of vertices , sorted the list so the highest z was first

vertexCreator from the coordinates of the first element in the list

pointOnLineOverlayer to split the the line at that point

rebuilt the resulting two lines into a polygon. (an areaBuilder might pick them up in the correct order anyhow, if not then using a LineCombiner after you switch the order of the lines would work)

Hi @od10​ Here's a workspace showing @jdh​ 's idea. The tricky part is hoping that the 2 lines will be in the right order to make the vertex with the highest Z value the start/end point of the polygon. I found that the TopologyBuilder did this consistently.

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