## Fidget updates: ZLevel's (z-index) support
Notice that the dropdowns go up when too close to the bottom!
This demo shows the results of some tweaking I did yesterday to add z-index
(ZLevel) support in OpenGL Fidgets. It's limited to only 4 layers due to the
way it's implemented. Here's the layers:
ZLevel* = enum
## The z-index for widget interactions
ZLevelBottom
ZLevelDefault
ZLevelRaised
ZLevelOverlay
Run
Essentially each z-index layer is rendered in order but only items visible on
that layer are drawn, though layouts are fully calculated. I haven't run
benchmarks to test the overhead, but it hasn't noticeably affected rendering
speed. CPU usage hasn't noticeably changed either.
Furthermore mouse/keyboard interactions follow the ZLevel precedents where
lower levels are overshadowed. This simplifies making the dropdown code above
and avoids annoying "overlapping nodes both got a click". It also simplifies
worrying about the order widgets are drawn, which makes it possible to use
Horizontal and Vertical blocks without worrying.
