[GRASS-dev] [GRASS GIS] #3033: Cairo and PS drivers display only one raster or vector for SVG and PS

[GRASS GIS]

#3033: Cairo and PS drivers display only one raster or vector for SVG and PS
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  Reporter:  wenzeslaus  |      Owner:  grass-dev@…
      Type:  defect      |     Status:  new
  Priority:  major       |  Milestone:  7.2.0
 Component:  Display     |    Version:  svn-trunk
Resolution:              |   Keywords:  d.mon, cairo, ps, SVG, vector
       CPU:              |  graphics
  Unspecified            |   Platform:  Unspecified
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Comment (by glynn):

 Replying to [comment:5 wenzeslaus]:

 > That's why I wanted to avoid that. It seems that having the rendering
 functionality split into commands creates many problems.

 It also provides flexibility that a monolithic approach such as ps.map
 inherently lacks.

 > Makes sense, of course. That's why we need Cairo driver to support it.

 Another option, which isn't entirely trivial but possibly simpler than
 (reliably) merging SVG documents, would be a "capture" driver which
 serialises the driver calls and their parameters to a file for subsequent
 rendering. This way, you could capture the output from multiple d.*
 commands then render the final result via the cairo driver (or any other
 driver, but it's only really useful in conjunction with cairo's vector
 output formats).

 Structurally, this would be quite similar to the PS driver. Actually,
 parsing the output from the PS driver would probably work (mostly), and
 avoid the need for an additional driver.

 Except, we'd need to add the text methods (the cairo driver supports
 "driver" fonts which cause text rendering to be passed to the driver; the
 PS driver currently only supports stroke and freetype fonts which are
 converted to lines or rasters by the driver library then rendered using
 the driver's line/raster methods).

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Ticket URL: <https://trac.osgeo.org/grass/ticket/3033#comment:7>
GRASS GIS <https://grass.osgeo.org>