[GRASS-dev] [GRASS GIS] #2932: z values read instead of intensity in r.in.lidar

[GRASS GIS]

#2932: z values read instead of intensity in r.in.lidar
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  Reporter:  dnewcomb  |      Owner:  grass-dev@…
      Type:  defect    |     Status:  new
  Priority:  normal    |  Milestone:  7.1.0
 Component:  Default   |    Version:  svn-trunk
Resolution:            |   Keywords:
       CPU:  x86-64    |   Platform:  Linux
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Comment (by wenzeslaus):

 The current implementation of `-i` uses intensity instead of z from the
 beginning and applies it for all subsequent operations:

 {{{
 #!c
 if (intens_flag->answer)
     /* use z variable here to allow for scaling of intensity below */
     z = LASPoint_GetIntensity(LAS_point);
 else
     z = LASPoint_GetZ(LAS_point);
 }}}

 Thus both `zrange` and `base_raster` are working with intensity. Is this
 the behavior you observe?

 I think it does not make much sense and `zrange` and `base_raster` always
 using z is more expected and useful behavior. This raises two questions.

 Does it make sense to have `intensity_range` or `irange` and
 `intensity_scale`?

 Is it OK to make this change when it is in fact changing behavior? Is the
 previous behavior simply a bug, so we can just changed it? We are talking
 about `zrange` and `zscale` (`base_raster` is 7.1 only). MarkusN added the
 intensity in r61480 with the aforementioned comment ''allow for scaling of
 intensity below''. Another flag (`-j` "stats on intensity, filters on z")
 or even and option (`values=z|intensity|combined`) can implement this in a
 backward compatible way for the price of complicating the interface and
 the code.

--
Ticket URL: <https://trac.osgeo.org/grass/ticket/2932#comment:1>
GRASS GIS <https://grass.osgeo.org>