[GEM-dev] [ pd-gem-Bugs-2905446 ] [DOCUMENTATION] pix_mask documentation error

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Bugs item #2905446, was opened at 2009-11-28 21:26
Message generated for change (Tracker Item Submitted) made by sistisette
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Category: Pixes (pix_ objects)
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Matteo Sisti Sette (sistisette)
Assigned to: Nobody/Anonymous (nobody)
Summary: [DOCUMENTATION] pix_mask documentation error

Initial Comment:
The help-patch for pix_mask contraddicts itself:
statement 1:
"Where ever the mask has a colored pixel, the alpha component of the other image will be set to 0 (transparent)."
statement 2:
"Basically, the luminance-value of the right pix will become the alpha-value of the left pix."

These sentences obviously contraddict each other.
According to statement 1, non-zero luminance would produce zero alpha, while according to statement 2 the opposite is true. Also, according to statement 1 at most 2 values of alpha would be possible (zero and non-zero, presumably 1), while according to statement 2, intermediate values in the range 0..1 seem to be possible.

I think the correct one is (2).

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