Re: [PATCH] stroke_extents: Use a polygon instead of traps
Chris Wilson <[email protected]>
| Newsgroups | gmane.comp.lib.cairo |
|---|---|
| Message-ID | <[email protected]> |
On Fri, Jun 14, 2013 at 03:18:10PM +0200, Uli Schlachter wrote: > Instead of calculating the extents of a cairo_path_fixed_t by converting it into > traps and getting the traps' extents, this patch implements this operation via > converting to a polygon and using the polygon's extents. > > This fixes the "get-path-extents" test without breaking anything else. IMHO this > commit papers over a bug from commit 3cf6551ac7 (see bugzilla), but I am not > really sure and can only guess. Yes, the bug is in the expectations of the test case; we are expecting Cairo to provide a perfect result, but Cairo is working to a specified tolerance. This tolerance allows it to skip many stages of refinement and cuts down on its overhead, but also incurs a loss of geometric precision. I fixed the test case to respect the tolerance that it asks of Cairo. This patch is an improvement that avoids the intermediate trapezoidation. -Chris -- Chris Wilson, Intel Open Source Technology Centre -- cairo mailing list [email protected] http://lists.cairographics.org/mailman/listinfo/cairo