[GRASS-dev] [GRASS GIS] #2649: r.to.vect diagonals defect fixed

[GRASS GIS]

#2649: r.to.vect diagonals defect fixed
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 Reporter:  byronbest  |       Owner:  grass-dev@…              
     Type:  defect     |      Status:  new                      
 Priority:  normal     |   Milestone:  7.0.1                    
Component:  Raster     |     Version:  unspecified              
 Keywords:  r.to.vect  |    Platform:  All                      
      Cpu:  x86-64     |  
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Comment(by byronbest):

 Consider the result of r.drain, which is an already-thinned line of pixel
 centres, obviously in "runs" of x,y moving +/- 1 in x and/or y. We'd like
 for the runs be "collapsed" into only the corners where the direction
 changes. Further, we'd like that running the stream on another grid
 respect that we also need the corners where the color or value on the
 resulting line changes. The segments will be given the color of the pixel
 under the second of every pair.
 r.to.vect already handles these runs when they are straight in the x or y,
 but not in diagonals where both x and y change.
 The attached before/after screen shots show where this has become a
 visible defect.

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Ticket URL: <http://trac.osgeo.org/grass/ticket/2649#comment:3>
GRASS GIS <http://grass.osgeo.org>