I found strange behavior (I think it's a bug) using a lot of layers with comp-op="dst-out" and opacity="0.5" settings. I made a small test-case for this issue: http://126.96.36.199/~andrey/tiles/temp/testcase.zip
There are 2 images. The first image made with only layers "0" and "RGB" enabled:
With this image the only one thing is strange: opacity of the low grey part not 0.5, but 0.49 (or 127 instead of 128). So (128,128,128,128) became (128,128,128,127).
The second image made with the layer "0" is turned off:
A lot of issues here.
a) The RGB-squares now with alpha transparency 195 of 255 (0.76).
b) The first line of 6 gray squares with invalid color and opacity:
But the second image should be the same as the first!
Hope this helps.
(Artem, did you received my letter about this issue?)
Any help on this bug?
This is blocking issue for our new hybrid maps design.
@Andrey-VI - thanks for reporting, I'll look into this issus asap.