Fix ifi2 condition for looking for crossings between polygon 1 and 2.
Fix ifi2 condition for looking for crossings between polygon 1 and 2.

For split2 store data in order of increasing index of polygon 2 to
preserve the orientation.

(These changes to fill_intersection_polygon made page 2 of example 25, where
both polygons have positive orientation (see
http://en.wikipedia.org/wiki/Curve_orientation for a discussion of this)
give correct filling results for the first time for the
-DFILL_INTERSECTION_POLYGON=ON case.

Transform polygon 1 to have positive orientation in the
-DFILL_INTERSECTION_POLYGON=ON part of plP_plfclp.  This made page 1 of
example 25 (where polygon 1 had negative orientation) work correctly.
Thanks to Arjen for this idea.

There are still issues with pages 3 and above of example 25 for
-DFILL_INTERSECTION_POLYGON=ON.

These changes should not affect the default -DFILL_INTERSECTION_POLYGON=OFF
case.


svn path=/trunk/; revision=10727

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