I am working a bit with spatial data, and am running a lot through Blender because ArcGIS can't handle it as well. I've come across an issue that I can't seem to figure out, it affects a few files, but this is the simplest one.
The shape was made by extruding a polygon between two tins in ArcGIS, creating a Multipatch feature. This was exported from ArcGIS as a WRL file. The volume in ArcGIS was calculated as 144.878252 m3, which given the rough dimensions (10 m x 6m x 2.4m) is correct accounting for variation of the non-smooth top surface.
When the WRL is imported into Blender, the calculated volume (using the 3D printing add-on) gives a value of 176.16027832 m3.
The reason why I need to calculate volumes in Blender is that is there are more complex shapes that ArcGIS will not calculate the volume for.
I am running Blender 2.77. Any help would be appreciated.