[mapguide-trac] #743: AGG Renderer does not properly handle transparency for non-PNG image formats (was: PNG8 format doesn't support transparency)

[MapGuide Open Source]

#743: AGG Renderer does not properly handle transparency for non-PNG image
formats
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   Reporter:  gingerbbm          |       Owner:       
       Type:  enhancement        |      Status:  new  
   Priority:  medium             |   Milestone:       
  Component:  Rendering Service  |     Version:  2.2.0
   Severity:  minor              |    Keywords:       
External_id:                     |  
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Comment(by jng):

 As a test I just tried setting the renderer to GD in serverconfig.ini

 The PNG8 tiles and overlays produced are transparent.

 As another experiment, I tried doing GIF dynamic overlays in both
 renderers:

  * GD produces transparent GIFs
  * AGG produces opaque GIFs

 So this leads me to believe the AGG renderer is the culprit. Or more
 specifically
 [http://trac.osgeo.org/mapguide/browser/branches/2.2/MgDev/Common/Renderers/AGGImageIO.cpp#L981
 the code starting here]

 Ticket title update to reflect these findings

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Ticket URL: <http://trac.osgeo.org/mapguide/ticket/743#comment:9>
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