[whatwg] hit regions: clearing of regions
cabanier at gmail.com
Mon Mar 10 17:19:22 PDT 2014
Currently, the specification states that if you create a region and then
create another region that completely covers region, the first region is
removed from the hit region list 
This is a complex operation that involves either drawing the regions to a
bitmaps and counting pixels, or path intersection.
It is also unintuitive because an author might expect that he could remove
the second region and still have the first region active.
What was the reason that this was added to the spec?
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