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I have converted a polygon shapefile of a forest to a multipatch, and now would like to have the multipatch appear 25m tall. I've added a column 'Height' to the attribute table with the number 25 in each cell.

I was able to view the 25m-high woodland easily when it was just a polygon (through using the extrude function), but am unable to achieve the same now that it has been converted. It only shows the footprint of the woodland, not the entire 3-dimensional mass. Is there a simple solution to this which I am missing?

Also, if using tools such as Skyline or Visibility, does it matter that forest isn't being rendered in 3D?

Additional info: The ultimate aim is to determine how much of the surrounding view will be obstructed by the forest once it has grown to 25m high, through using tools in the Visibility toolbox. The multipatch in question and the initial polygon are floating on a TIN.

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Its quite simple actually: convert your forest polygon to TIN, use Extrude Between with the forest layer and the TIN used as a base elevation and there you go, your multipatch file with x y z.

If you want your forest +25 meters elevation layer to follow your base TIN and change it's slope where the base TIN changes it you have to do the next steps:

  • Use TIN Nodes to convert TIN to vector point;
  • Select a larger area than your forest layer;
  • Clip the above selected points;
  • Open attribute table and add a new long integer field;
  • Add 25 to the existing elevation of the TIN;
  • Recreate the forest layer as a TIN using the clipped points;
  • Extrude between untouched base TIN and the new forest +25 TIN;
  • Sit back and enjoy your multipatch.

Related to the Visibility/Skyline tools, I haven't really used them, but afaik, for Visibility, one needs the obstacle to be loaded.

  • Hi alecsx, thanks for that. I'll try it out as soon as I'm back in the office in a couple days, and let you know it goes. Looks pretty straightforward so am remaining hopeful... – Luke Mar 25 '18 at 20:38

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