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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal>I'm trying to use GEOS to evaluate geometric predicates
while using a Precision Model that is lower than the default. It looks as
though the Precision Model is only used for certain operations, and in
particular ignored when evaluating the border conditions of whether lines touch
each other. I've read the JTS technical docs, and they seemed to imply that
this type of thing should work.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>My test is to create two polygons side by side, with one
touching edge. The TOUCH predicate evaluates true. I then move one polygon away
by DBL_EPSILON (1e-16), and evaluate the predicate again. This time it is
false. A brief step through and code search seems to reveal that the precision
model is not used here.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Am I completely missing the point?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks,<o:p></o:p></p>
<p class=MsoNormal>Ben<o:p></o:p></p>
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