If the client is small (< 128 pixels in any ward),
then the shadows overlap and create dark lines behind clients.
This is a problem mosly with pop-up menues. The lines become observable
when the menu has less than three items. The other case is when
the client doesn't restrict its size when resizing (try
'weston-eventdemo --max-width=1 --max-height=1' for example)
This fixes a part of the bug:
https://bugs.freedesktop.org/show_bug.cgi?id=78511
v2:
- rework computing of the size of corners
- rewrite some comments
- rename tile_mask to render_shadow (in separate patch)
Signed-off-by: Marek Chalupa <mchqwerty@gmail.com>
Tested-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
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