[GRASS-dev] [GRASS GIS] #2033: Moving g.pnmcomp to lib/display to improve render performance of wxGUI

[GRASS GIS]

#2033: Moving g.pnmcomp to lib/display to improve render performance of wxGUI
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  Reporter:  huhabla      |       Owner:  grass-dev@…                     
      Type:  enhancement  |      Status:  closed                          
  Priority:  major        |   Milestone:  7.0.0                           
 Component:  wxGUI        |     Version:  svn-trunk                       
Resolution:  worksforme   |    Keywords:  display, Python, multiprocessing
  Platform:  All          |         Cpu:  All                             
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Changes (by huhabla):

  * status:  new => closed
  * resolution:  => worksforme


Comment:

 My conclusion:

  * Moving the code of g.pnmcomp, d.vect, d.rast ... d.* into the display
 library for speedup reason is not meaningful. It might be meaningful when
 we decide to implement the d.* modules as Python modules that communicate
 with the wx display using sockets instead of files to call the rendering
 backend. Well, the same can be achieved by implementing python wrapper
 modules around the display modules ... so it might be not meaningful at
 all.

  * The current wxGUI rendering approach using PPM and g.pnmcomp seems to
 be the most efficient considering the fact that the cairo driver is not
 yet available in the windows version of grass7. It seems to me that using
 PIL will not provide a large speedup benefit over g.pnmcmop especially for
 large images.

  * A small speedup can be achieved when calling the d.* modules in
 parallel in the GUI, especially when several maps need to be re-rendered.

  * IMHO the only way to speedup the rendering is to make d.rast and d.vect
 faster.

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Ticket URL: <http://trac.osgeo.org/grass/ticket/2033#comment:10>
GRASS GIS <http://grass.osgeo.org>