we are using some button overlays in our augmentation. The Overlays are PNG-Files with transparent backgrounds. They can be moved also along the Z axis, so that they can overlap in 3d space (nice effects, and quite nice to show a "faked" shadow under the buttons). We experience some problems, so maybe you have an idea (see the screenshot):
Layer 1 - z=0 - this is the "main" motive (the girl)
Layer 2 - z=0,01 this is the button shadow - as you can see the transparency is respected (you can see the main layer below)
Layer 3 - z= 0,2 this is the button graphic - transparency toward layer1 is respected, transparency toward layer 2 is not respected (the shadow PNG is blocked out in the transparent area)
Any idea what's happening there?