[HitCanvas] Find way to fully remove anti-aliasing of shapes

[techniq]

This causes tooltip hiding (flickering) as the aliased color on the edges is not in the map. Might be able to set some kind of threshold to match, but that will slow down the lookup a good bit.

Sadly, image-rendering: pixelated (or any other value) is not the solution. https://developer.mozilla.org/en-US/docs/Web/CSS/image-rendering

There is also the r-tree approach to investigate, but I liked the simplicity of easy to debug nature of the HitCanvas approach.