Changes between Version 14 and Version 15 of SomeSplitting


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Timestamp:
Mar 8, 2013, 7:42:07 AM (10 years ago)
Author:
mloskot
Comment:

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  • SomeSplitting

    v14 v15  
    11= Discussion of Methods and API for Splitting an Oversize Polygon =
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     3Discussion outline:
     4 * It is often desirable to "split" a POLYGON with a high number of vertices into some number of smaller POLYGONs.
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    4 * It is often desirable to "split" a POLYGON with a high number of vertices into some number of smaller POLYGONs.
     6 * From a user's perspective, some GIS processes result in very large POLYGON, for example 10,000 or 100,000 or more, vertices.  There is a case to be made that PostGIS users would benefit from standard calls to take a single POLYGON as an input,  and output some GEOMETRYCOLLECTION of POLYGON that are "equivalent", while respecting the problems inherent with the numeric precision model used.
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    6 * From a user's perspective, some GIS processes result in very large POLYGON, for example 10,000 or 100,000 or more, vertices.  There is a case to be made that PostGIS users would benefit from standard calls to take a single POLYGON as an input,  and output some GEOMETRYCOLLECTION of POLYGON that are "equivalent", while respecting the problems inherent with the numeric precision model used.
     8 * GEOS performs poorly as a POLYGON increases to a very large number of vertices, even in simple cases.
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    8 * GEOS performs poorly as a POLYGON increases to a very large number of vertices, even in simple cases.
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    10 * For the sake of discussion. let us assume we are operating on a POLYGON with a single outer ring, that is formally valid.
     10 * For the sake of discussion. let us assume we are operating on a POLYGON with a single outer ring, that is formally valid.
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