#636: r.thin creates triangle at acute intersection of two lines
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Reporter: needelsd | Owner: grass-dev@lists.osgeo.org
Type: defect | Status: new
Priority: normal | Milestone: 6.4.0
Component: Raster | Version: 6.4.0 RCs
Keywords: r.thin | Platform: MacOSX
Cpu: OSX/Intel |
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I have rasters that were generated using v.rast followed by r.buffer.
Using r.thin on such a raster occasionally creates a triangle at an
intersection instead of the expected two intersecting lines. All of the
examples I have seen involve relatively acute angles (less than 25
degrees??).
This result is easily seen by using r.to.vect to create a vector, which
then needs v.clean to remove dangles. I have attached a screenshot that
shows the original (fat) raster in magenta, the vector with dangles in
white, and the cleaned vector as (a thinner) green. There are numerous
acute angles that generate the vectors I would expect, with one exception
in the center.
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Ticket URL: <http://trac.osgeo.org/grass/ticket/636>
GRASS GIS <http://grass.osgeo.org>