From b4230ebb3c2d5019fdf9468607c1e8b1e7205910 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Misiewicz?= <misiewicz.michal@outlook.com>
Date: Thu, 20 Jul 2017 09:12:46 +0200
Subject: [PATCH] PolygonBound.contains() fix (#4553)

* PolygonBound.contains() fix

* style fix

* code refactor and dependency-reduced-pom.xml deletion

* refactor bug fix

* requested changes

* method extraction

* formatting issues fix
---
 .../spatial/search/PolygonBound.java          | 34 ++++++++++++++++---
 .../spatial/search/PolygonBoundTest.java      | 31 +++++++++++++++++
 2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/bytebuffer-collections/src/main/java/io/druid/collections/spatial/search/PolygonBound.java b/bytebuffer-collections/src/main/java/io/druid/collections/spatial/search/PolygonBound.java
index 6bc9bb26eed..fbca73dc255 100755
--- a/bytebuffer-collections/src/main/java/io/druid/collections/spatial/search/PolygonBound.java
+++ b/bytebuffer-collections/src/main/java/io/druid/collections/spatial/search/PolygonBound.java
@@ -124,11 +124,21 @@ public class PolygonBound extends RectangularBound
     int j = polyCorners - 1;
     boolean oddNodes = false;
     for (int i = 0; i < polyCorners; i++) {
-      if ((ordinate[i] < coords[1] && ordinate[j] >= coords[1]
-           || ordinate[j] < coords[1] && ordinate[i] >= coords[1])
-          && (abscissa[i] <= coords[0] || abscissa[j] <= coords[0])) {
-        if (abscissa[i] + (coords[1] - ordinate[i]) / (ordinate[j] - ordinate[i]) * (abscissa[j] - abscissa[i])
-            < coords[0]) {
+
+      if (abscissa[i] == coords[0] && ordinate[i] == coords[1]) {
+        return true;
+      }
+
+      if (isPointLayingOnHorizontalBound(i, j, coords)) {
+        return true;
+      }
+
+      if (between(ordinate[i], ordinate[j], coords[1]) && (abscissa[j] <= coords[0] || abscissa[i] <= coords[0])) {
+        float intersectionPointX = abscissa[i] + (coords[1] - ordinate[i]) / (ordinate[j] - ordinate[i]) * (abscissa[j] - abscissa[i]);
+
+        if (intersectionPointX == coords[0]) {
+          return true;
+        } else if (intersectionPointX < coords[0]) {
           oddNodes = !oddNodes;
         }
       }
@@ -137,6 +147,20 @@ public class PolygonBound extends RectangularBound
     return oddNodes;
   }
 
+  private boolean isPointLayingOnHorizontalBound(int i, int j, float[] coords)
+  {
+    return ordinate[i] == ordinate[j] && ordinate[j] == coords[1] && between(abscissa[i], abscissa[j], coords[0]);
+  }
+
+  private static boolean between(float a, float b, float x)
+  {
+    if (a <= b) {
+      return a <= x && x <= b;
+    } else {
+      return b <= x && x <= a;
+    }
+  }
+
   @Override
   public Iterable<ImmutablePoint> filter(Iterable<ImmutablePoint> points)
   {
diff --git a/bytebuffer-collections/src/test/java/io/druid/collections/spatial/search/PolygonBoundTest.java b/bytebuffer-collections/src/test/java/io/druid/collections/spatial/search/PolygonBoundTest.java
index 73ac85e6580..b9c3812e427 100755
--- a/bytebuffer-collections/src/test/java/io/druid/collections/spatial/search/PolygonBoundTest.java
+++ b/bytebuffer-collections/src/test/java/io/druid/collections/spatial/search/PolygonBoundTest.java
@@ -46,4 +46,35 @@ public class PolygonBoundTest
         PolygonBound.from(new float[]{1F, 2F, 3F}, new float[]{0F, 2F, 0F}, 2).getCacheKey()
     ));
   }
+
+  @Test
+  public void testContains()
+  {
+    final PolygonBound triangle = PolygonBound.from(new float[]{1f, 4f, 7f}, new float[]{ 1f, 4f, 1f});
+    final float delta = 1e-5f;
+
+    Assert.assertTrue(triangle.contains(new float[]{1f, 1f}));
+    Assert.assertFalse(triangle.contains(new float[]{1f, 1f - delta}));
+    Assert.assertFalse(triangle.contains(new float[]{1f, 1f + delta}));
+    Assert.assertTrue(triangle.contains(new float[]{1f + delta, 1f}));
+    Assert.assertFalse(triangle.contains(new float[]{1f - delta, 1f}));
+    Assert.assertTrue(triangle.contains(new float[]{1f + delta, 1f}));
+    Assert.assertFalse(triangle.contains(new float[]{1f - delta, 1f}));
+    Assert.assertTrue(triangle.contains(new float[]{5f, 1f}));
+    Assert.assertFalse(triangle.contains(new float[]{1f, 5f}));
+    Assert.assertTrue(triangle.contains(new float[]{3f, 2f}));
+
+    final PolygonBound rightTriangle = PolygonBound.from(new float[]{1f, 1f, 5f}, new float[]{ 1f, 5f, 1f});
+
+    Assert.assertTrue(rightTriangle.contains(new float[]{1f, 5f}));
+    Assert.assertTrue(rightTriangle.contains(new float[]{2f, 4f}));
+    Assert.assertTrue(rightTriangle.contains(new float[]{2f - delta , 4f}));
+    Assert.assertFalse(rightTriangle.contains(new float[]{2f + delta, 4f}));
+    Assert.assertTrue(rightTriangle.contains(new float[]{2f, 4f - delta}));
+    Assert.assertFalse(rightTriangle.contains(new float[]{2f, 4f + delta}));
+    Assert.assertTrue(rightTriangle.contains(new float[]{3f - delta, 3f}));
+    Assert.assertFalse(rightTriangle.contains(new float[]{3f + delta, 3f}));
+    Assert.assertTrue(rightTriangle.contains(new float[]{3f, 3f - delta}));
+    Assert.assertFalse(rightTriangle.contains(new float[]{3f, 3f + delta}));
+  }
 }