Opened 20 years ago
Closed 10 years ago
#515 closed defect (wontfix)
OGRGeometry::Intersect does not work correctly for geographic coordinate system
Reported by: | Owned by: | warmerdam | |
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Priority: | normal | Milestone: | |
Component: | OGR_SRS | Version: | unspecified |
Severity: | normal | Keywords: | |
Cc: | gdal@… |
Description (last modified by )
OGRGeometry Intersect method does not work correctly in a geographic coordinate system (lat/lon coordinates), because it does not account for periodicity (i.e. "wrap-around" of lon-coordinate at dateline). OGRGeometry already has an associated spatial reference (with the method IsGeographic()). However, a remaining problem is that polygon edges are not well-defined in such a coordinate system (although the shortest connection is probably a reasonable assumption).
As a test case: 1) download & tar xzf the following wrs2 zone definition file: ftp://ftp.glcf.umiacs.umd.edu/www/shapefile/wrs2.tar.gz 2) execute 'ogrinfo -al wrs2.shp -spat 42 42 44 44' ogrinfo will wrongly report wrs2 zones crossing the dateline, because the intersection routines' min-max check inverts the longitudal extent of these cells.
Change History (3)
comment:3 by , 17 years ago
Description: | modified (diff) |
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comment:4 by , 10 years ago
Resolution: | → wontfix |
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Status: | assigned → closed |
From http://www.gdal.org/classOGRGeometry.html
Intersect (OGRGeometry *) const CPL_WARN_DEPRECATED("Non standard method. Use Intersects() instead")
Because this method does not exist if won't fix either.