Heron

This is the first release of an add-on which enables the import of GIS data from various sources into the Rhino/Grasshopper environment, located, scaled and cropped based on an Earth Anchor Point and a clipping polygon.  Sources of GIS data include Shapefiles, USGS IMG/HGT Elevation files and ArcGIS REST Services over the web.

The add-on includes eight components in two categories:

GIS REST

• ESRI REST Service Geocode. Get a Decimal Degree coordinate from an address or Point-of-Interest with the Geocode service provided by ESRI.  
• Get REST Service Layers. Discover data layers  from various data sources on the web. If the layers are a vector type, they return data similar to a shapefile, with geometry and associated data fields.  To be used with the Get REST Vector or Get REST Raster component depending on the data type.
• Get REST Raster. Grabs JPGs of imagery from the specified web source.  Once downloaded to a folder the image can be located and scaled to match the boundary in real world units (meters) with the use of the image frame.
• Get REST Vector.  Queries the web source for geometry and associated data fields.  For instance demographic information from the US Census can be referenced.

GIS Tools

• Decimal Degrees to XY.  Convert Decimal Degrees to XY coorindates based on the EarthAnchorPoint.
• Import SHP.  Imports Shapefiles using OGR Libraries. Output is in the form of points (for now) which can then be connected to form polylines.  For Shapefiles with Multipolygons (ie building footprints with courtyards), the component reads mulitple branches of points per Feature.  To get the footprint, you will need to draw a polyline for each branch, shift the branches and use the Boundary Surface component.
• Import Topo.  Imports IMG and (STRM) HGT files using GDAL Libraries.  Output is in the form of a mesh.
• Set EarthAnchorPoint.  Runs a macro to set the Earth Anchor Point in Rhino.  This is important to minimize distortion translating from the curved surface of the Earth to Euclidean coordinates.

Special thanks go to the vibrant GH community, the masterful guidance of Andrew Heumann and endless patience of George Waters.