I'm trying to create a mask with a customized shape, meaning,
not one you can draw in code. I have an image of that shape in a
Photoshop file. The outside of the image is gray and the center is
transparent (imagine a transparent star in the center of a gray
field and you have the idea).
What I need to do is permit the user to drag another image
onto a canvas that has this outline shape/image on it. It the user
attempts to drop the image on the gray border, I want nothing to
happen, meaning I want the drop to "fail." However, if the user
drops the image on the center, transparent portion of the image, I
want the drop to succeed.
Additionally (and this is the tough part), if the user drops
the incoming image right on the border of the transparent center
and the gray outside, I want the portion of the dropped image in
the transparent section to show, but I want the gray to cover over
the remainder of it.
I read a few things dealing with alpha channels in Photoshop
and how they can be used to create a mask, but I'm not having any
luck. It seems to me what I REALLY need is an image that has an
ABSENT center, not a transparent center. I can then put the drop
listener on the canvas beneath. Does anyone know how to create such