CopyRect that supports alpha

[arthurprs]

current CopyRect don't support alpha, i have to create 2 canvas for a simple watermark draw,

a "CopyRectWithAlpha" would be great.


Arthur.

[Galfar]

CopyRectWithAlpha would just create those 2 canvases, but then it couldn't be in
Imaging.pas unit as CopyRect is, because this unit shouldn't use ImagingCanvases unit.
I'll probably create some descendants of TBaseImage with canvas automatically created for them
(like in VCL/LCL where you can write Image.Canvas.Draw(..)).