[GEM-dev] [ pd-gem-Bugs-3044953 ] pix_mix colorspace error

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Bugs item #3044953, was opened at 2010-08-14 16:07
Message generated for change (Tracker Item Submitted) made by nobody
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Category: Pixes (pix_ objects)
Group: osx
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Nobody/Anonymous (nobody)
Assigned to: Nobody/Anonymous (nobody)
Summary: pix_mix colorspace error

Initial Comment:
I was working on a gem-driven (gem 0.91.3) video mixing patch and needed some gridflow functions. Both [#to_pix] and [#from_pix] worked fine only when rendered directly to a texture. When I tried to [pix_mix] the output of the [#to_pix] object I got a crazy blue shade upon the mixed picture. I ended up knowing it was due to an incongruence in colorspaces, for some reasons the alpha channel and the blue channel were inverted. I fixed with a gridflow function to swap the channels, but I guess it's just a workaround. Probably [pix_mix] doesn't handle in the right way the colorspace without noticing it (no error output). Sample patch attached.

According to ClaudiusMaximum the bug could be found here:
Gem/src/Base/GemPixDualObj.cpp:84:  case GL_RGBA: case GL_BGRA_EXT:  \
Gem/src/Base/GemPixDualObj.cpp:85:    found=true; FUN_RGBA; break;  \

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=507079&aid=3044953&group_id=64325