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true live 3d mapping

November 18 2010 | 0 comments
Categories: 3D Mapping

I work in a surface mine and part of my job is mapping high-walls in the mine. I would like to know if it is possible to map a vertical face as a vertical face in Arc then view it in plan view with the data represented with out distortion. Is it possible to map in this manner?

Mapping Center Answer:

Yes, you can map vertical faces in ArcGIS. I'll assume you're starting with 2D terrace polygons and want completely vertical walls between each terrace level. The fastest way to go about this is to first add z information for your terrace levels, either as an attribute in the attribute table or natively in the feature if your polygon is z-enabled. Then you can bring the polygons into ArcScene (or ArcGlobe) and do the following:

  1. Set the base height for each terrace in Layer Properties > Base Heights tab. If your z information for each terrace is an attribute, select the "Set a constant value or expression" and select that attribute field using the calculator icon. If your polygons are already z-enabled, simply use the "Use elevation values in the layer’s feature" option.
  2. Set the extrusion value in the Layer Properties > Extrusion tab. After clicking the checkbox, specify the elevation you want each terrace to extrude down to (the elevation of the lowest terrace, most likely), and select the drop-down menu to apply the extrusion "Using it as a value that features are extruded to".

This will result in a solid volume of stacked terraces. If you want to maintain the z-information you specified in the above steps, you can now export the extruded polygons to a 3D multipatch feature using the Layer 3D to Feature Class tool.

If you'd rather not create a solid volume and would instead like a "house of cards" with a void inside created from vertical and horizontal polygons, the basic approach is similar. For the vertical portions, just convert your polygons to lines with the Feature to Line tool, and then extrude the line portions that represent each vertical face.

As for viewing your 3D feature in plan view, load either your extruded polygons/lines or your multipatch feature into ArcScene. In the View > View Settings menu, the default projection is Perspective, but you can change this to a top-down Orthographic (2D) view, similar to what you'd see in ArcMap.

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