I'm using "ImageMagick 7.0.3-2 Q16 x64 2016-10-02" on "Windows 10 64". Following up on a discussion
in THIS thread, in my current version and a couple other recent versions, the "-composite" operation does not always behave as I might expect. If I run a simple command to create a transparent canvas, then a gradient canvas, then composite that gradient onto the transparent like this...
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magick -size 360x360 xc:none -size 240x240 gradient:red-blue -composite test_A.png
... I would expect the result to be a 240x240 gradient placed in the upper left corner of a 360x360 transparent image. What I actually get is just a 360x360 entirely transparent image with no visible overlay at all.
If I add "-alpha on" after creating the gradient canvas like this...
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magick -size 360x360 xc:none -size 240x240 gradient:red-blue -alpha on -composite test_B.png
... the gradient appears in the upper left corner, the result I would have expected from the first command. It doesn't seem like adding "-alpha on" should be necessary to get the composite to work.
Is this something that requires the attention of the developers, or am I overlooking something?
