[GRASS-dev] [GRASS GIS] #3600: m.nviz.image doesn't produce any output

[GRASS GIS]

#3600: m.nviz.image doesn't produce any output
--------------------------+-------------------------
  Reporter:  guano        |      Owner:  grass-dev@…
      Type:  defect       |     Status:  new
  Priority:  normal       |  Milestone:
 Component:  Default      |    Version:  7.0.4
Resolution:               |   Keywords:
       CPU:  Unspecified  |   Platform:  MacOSX
--------------------------+-------------------------

Comment (by hellik):

 Replying to [comment:54 hcho]:
 > Only Windows defines double buffering; that's why Linux works without
 buffer swapping because it has only one buffer. BUT, glGetError() still
 returns GL_INVALID_OPERATION according to https://www.khronos.org/registry
 /OpenGL-Refpages/gl4/html/glReadBuffer.xhtml. Probably, that's why some
 Linux drivers and MacOS don't work at all.
 >
 > Windows is also broken because nviz draws to the back buffer, but it
 reads from the front buffer without buffer swapping.

 tested with

 {{{
 GRASS version: 7.5.svn
 GRASS SVN revision: r72969
 Build date: 2018-07-10
 Build platform: x86_64-w64-mingw32
 GDAL: 2.2.4
 PROJ.4: 4.9.3
 GEOS: 3.5.0
 SQLite: 3.17.0
 Python: 2.7.14
 wxPython: 2.8.12.1
 Platform: Windows-10-10.0.17134 (OSGeo4W)
 }}}

 {{{
 C:\>m.nviz.image elevation_map=elevation output=D:\temp\mnviz\elev
 perspective=15
 Loading raster map <elevation at PERMANENT>...
  100%
 Loading raster map <elevation at PERMANENT>...
  100%
 Translating colors from raster map <elevation at PERMANENT>...
  100%
 WARNING: Unable to get image of current GL screen
 ERROR: Failed to write image
 }}}

 {{{
 C:\>m.nviz.image elevation_map=elevation output=D:\temp\mnviz\elev
 perspective=15 format=tif
 Loading raster map <elevation at PERMANENT>...
  100%
 Loading raster map <elevation at PERMANENT>...
  100%
 Translating colors from raster map <elevation at PERMANENT>...
  100%
 WARNING: Unable to get image of current GL screen
 ERROR: Failed to write image
 }}}

-- 
Ticket URL: <https://trac.osgeo.org/grass/ticket/3600#comment:58>
GRASS GIS <https://grass.osgeo.org>