[R-sig-Geo] Geometry in tables - well-known binary?
Michael Sumner
mdsumner at utas.edu.au
Fri Aug 13 01:04:43 CEST 2004
Hello, does anyone know about "storing geometry in tables" using binary
record types? Manifold GIS 6.00 http://www.manifold.net supports the
storage of drawing object (points, lines and areas) coordinates in tables -
using a binary "Geometry" type. Geometry can be stored in databases (or
other tables supporting the binary Geom format such as .mdb).
These binary records can be accesed by SQL queries within Manifold
I.e. SELECT Geom(ID) AS [Geom], [Drawing].* FROM [Drawing]; results in
a table like:
<geom, area, branches: 1, coords: 10> 6 Area 1 10 -156.579937304075
These drawing objects can be reconstructed simply by importing or linking
to the table.
This makes Manifold a very powerful tool for manipulating vector data on
the fly.
Apparently there are "Geometry (SHP)" and "Geometry (WKB)" (well-known binary)
for ESRI geodatabases and OpenGIS respectively. Does anyone know how to read
such binary records using generic tools, like R?
I can already read table data from Manifold projects using RODBC, extending
this with
binary "Geometry in tables" could be very powerful.
Cheers, Mike.
###############################################
Michael Sumner - PhD. candidate
Maths and Physics (ACE CRC & IASOS) and Zoology (AWRU)
University of Tasmania
Private Bag 77, Hobart, Tas 7001, Australia
Phone: 6226 1752
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