[cairo] [PATCH] [in-fill] Treat on-edge queries as inside.

M Joonas Pihlaja jpihlaja at cc.helsinki.fi
Fri Feb 27 10:55:41 PST 2009

On Fri, 27 Feb 2009, Chris Wilson wrote:

> Jeff Muizelaar noted that the treatment of edges differed with firefox's
> canvas definition, which considers a point on any edge as inside. The
> current implementation has a similar definition to that of flash, for
> which the top and right edges are outside. Arguably, firefox has the more
> intuitive definition here...

This is the sort of change I would expect to break UIs, but given that 
it wasn't that long ago that we changed it to top-right, and no-one 
complained much (except the canvas implementors), it's probably better 
to change it to be consistent at least.  Namely, what's bugged me 
about the half-open definitions is that the topness or rightness is 
defined by device space, so from the point of view of user space the 
in-fill test on the edges is basically an arbitrary unpredictable 
choice that depends on the current transformation matrix.



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