Identified a new failure mode for polygons. Project: http://git-wip-us.apache.org/repos/asf/commons-math/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-math/commit/c29e3d68 Tree: http://git-wip-us.apache.org/repos/asf/commons-math/tree/c29e3d68 Diff: http://git-wip-us.apache.org/repos/asf/commons-math/diff/c29e3d68
Branch: refs/heads/master Commit: c29e3d681f2a46cc3288dc4f38925efbcf30c233 Parents: e11c000 Author: Luc Maisonobe <l...@apache.org> Authored: Sun Nov 30 11:40:27 2014 +0100 Committer: Luc Maisonobe <l...@apache.org> Committed: Tue Dec 2 15:24:31 2014 +0100 ---------------------------------------------------------------------- .../euclidean/twod/PolygonsSetTest.java | 37 ++++++++++++++++++++ 1 file changed, 37 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-math/blob/c29e3d68/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/PolygonsSetTest.java ---------------------------------------------------------------------- diff --git a/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/PolygonsSetTest.java b/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/PolygonsSetTest.java index 348ace8..c6c68a0 100644 --- a/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/PolygonsSetTest.java +++ b/src/test/java/org/apache/commons/math3/geometry/euclidean/twod/PolygonsSetTest.java @@ -24,6 +24,7 @@ import org.apache.commons.math3.geometry.euclidean.oned.IntervalsSet; import org.apache.commons.math3.geometry.euclidean.oned.Vector1D; import org.apache.commons.math3.geometry.partitioning.BSPTree; import org.apache.commons.math3.geometry.partitioning.BoundaryProjection; +import org.apache.commons.math3.geometry.partitioning.Hyperplane; import org.apache.commons.math3.geometry.partitioning.Region; import org.apache.commons.math3.geometry.partitioning.Region.Location; import org.apache.commons.math3.geometry.partitioning.RegionFactory; @@ -1107,6 +1108,42 @@ public class PolygonsSetTest { } + @Test + public void testThinRectangle() { + + RegionFactory<Euclidean2D> factory = new RegionFactory<Euclidean2D>(); + Vector2D pA = new Vector2D(0.0, 1.0); + Vector2D pB = new Vector2D(0.0, 0.0); + Vector2D pC = new Vector2D(1.0 / 64.0, 0.0); + Vector2D pD = new Vector2D(1.0 / 64.0, 1.0); + + // if tolerance is smaller than rectangle width, the rectangle is computed accurately + Hyperplane<Euclidean2D>[] h1 = new Line[] { + new Line(pA, pB, 1.0 / 256), + new Line(pB, pC, 1.0 / 256), + new Line(pC, pD, 1.0 / 256), + new Line(pD, pA, 1.0 / 256) + }; + Region<Euclidean2D> accuratePolygon = factory.buildConvex(h1); + Assert.assertEquals(1.0 / 64.0, accuratePolygon.getSize(), 1.0e-10); + Assert.assertTrue(Double.isInfinite(new RegionFactory<Euclidean2D>().getComplement(accuratePolygon).getSize())); + Assert.assertEquals(2 * (1.0 + 1.0 / 64.0), accuratePolygon.getBoundarySize(), 1.0e-10); + + // if tolerance is larger than rectangle width, the rectangle degenerates + // as of 3.3, its two long edges cannot be distinguished anymore and this part of the test fails + Hyperplane<Euclidean2D>[] h2 = new Line[] { + new Line(pA, pB, 1.0 / 16), + new Line(pB, pC, 1.0 / 16), + new Line(pC, pD, 1.0 / 16), + new Line(pD, pA, 1.0 / 16) + }; + Region<Euclidean2D> degeneratedPolygon = factory.buildConvex(h2); + Assert.assertEquals(1.0 / 64.0, degeneratedPolygon.getSize(), 1.0e-10); + Assert.assertTrue(Double.isInfinite(new RegionFactory<Euclidean2D>().getComplement(degeneratedPolygon).getSize())); + Assert.assertEquals(2 * (1.0 + 1.0 / 64.0), degeneratedPolygon.getBoundarySize(), 1.0e-10); + + } + private PolygonsSet buildSet(Vector2D[][] vertices) { ArrayList<SubHyperplane<Euclidean2D>> edges = new ArrayList<SubHyperplane<Euclidean2D>>(); for (int i = 0; i < vertices.length; ++i) {
