Non-closed multipatch

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02-02-2011 04:51 PM
PatrickSewell
New Contributor II
I have a collection of building polygons with height attributes. I hoped to convert these to multipatch, union them to aggregate parts of buildings together, and then calculate surface area and volume. I am able to create the multipatch, but for some reason many of the buildings are unclosed, leaving me unable to union or add z information. Why would 3d analyst create unclosed features from an extruded polygon? Is there any way to close the features?

Thanks,
Patrick Sewell
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4 Replies
Dan_Call
New Contributor II
I would love an answer from someone at ESRI on this. I am trying to create 3D spheres (actually a few other things too, but the spheres are a good start) from center points and intersect them to calculate volumes occupied by both spheres. I have tried several methods for creating multipatches in ArcGIS and they all produce feature classes with some or none of the multipatches coming out "closed". I even tried this tutorial directly from ESRI's ArcUser site:

http://www.esri.com/news/arcuser/1010/3danalysis.html

The first example gives a procedure for creating multipatches, and it produces multipatches that are not closed and therefore useless for intersecting.

So how do we create multipatches that are reliably "closed"? How is it possible that using ESRI's own tools to create the multipatches creates features that are useless with many other 3D Analyst tools, like Intersect 3D?
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JakubSisak
Regular Contributor
I am able to create the multipatch, but for some reason many of the buildings are unclosed

@Patric - could you post a screen capture of multipatches that are not closed?  I don't seem to be having this issue. I can symbolize points to shperes and extrude polygons then create multipatches that are closed.  See here
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JakubSisak
Regular Contributor
II am trying to create 3D spheres from center points and intersect them to calculate volumes occupied by both spheres.

@Dan - What method are you using?  I just replied to Patric's post and included a link to a discussion that shows how I can intersect spheres and calculate volume....
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YCLai
by
New Contributor
I'm having the same problem here.
I made a ground body by several steps, it turns out the multipatch isn't closed.(confirmed by "is closed 3d"). These are my steps,
1. use "Raster to tin" to create a ground surface tin from my dem raster.
2. Build a rectangular tin at certain elevation by using "create tin"(add in a rectangular polygon with z value and set sf_type as "hardreplace").
3. Use "extrude between", tin 1 is the ground surface tin, tin 2 is the rectangular tin. Feature class is a rectangular polygon bigger then tin 1 but smaller then tin 2.

I can successfully create the ground body I want (here). But the multipatch is not closed hence i can use those 3d analyst tools like intersect 3D.
Is there anyway to "close" the multipatch? Or there's other way that I can create a closed ground body I want?