From 1e7e07f349a61fda172d6741a2c8043651b574f2 Mon Sep 17 00:00:00 2001
From: Martin Felis <martin@fysx.org>
Date: Wed, 30 Aug 2023 08:53:49 +0200
Subject: [PATCH] Fixed infinite loop when querying CellsForLine.

---
 HexGrid.cs                        |  9 ++++++---
 tests/HexGridTests.cs             | 11 +++++++++++
 tests/NavigationComponentTests.cs | 12 ------------
 3 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/HexGrid.cs b/HexGrid.cs
index c6a3060..1de91f0 100644
--- a/HexGrid.cs
+++ b/HexGrid.cs
@@ -294,10 +294,12 @@ public class HexGrid : Resource
         List<HexCell> result = new List<HexCell>();
 
         HexCell toCell = GetHexAt(toPlane);
-        Vector2 direction = (toPlane - fromPlane).Normalized();
+        float distance = (toPlane - fromPlane).Length();
+        Vector2 direction = (toPlane - fromPlane) / distance;
 
         Vector2 currentPointPlane = fromPlane;
         HexCell currentCell = GetHexAt(currentPointPlane);
+        float currentDistance = 0;
 
         do
         {
@@ -311,8 +313,9 @@ public class HexGrid : Resource
                 out boundaryPlaneDistance);
             
             currentCell = currentCell.GetAdjacent(HexCell.NeighborDirections[neighbourIndex]);
-            currentPointPlane += direction * boundaryPlaneDistance * 1.001f;
-        } while (currentCell != toCell);
+            currentDistance += boundaryPlaneDistance * 1.001f;
+            currentPointPlane = fromPlane + direction * boundaryPlaneDistance;
+        } while (currentDistance < distance);
 
         result.Add(currentCell);
 
diff --git a/tests/HexGridTests.cs b/tests/HexGridTests.cs
index 8cbfc12..9275e5b 100644
--- a/tests/HexGridTests.cs
+++ b/tests/HexGridTests.cs
@@ -88,4 +88,15 @@ public class HexGridTests : TestClass
         Assert.Equal(HexCell.FromOffsetCoords(new Vector2(1, -1)), lineCells[1]);
         Assert.Equal(HexCell.FromOffsetCoords(new Vector2(2, 0)), lineCells[2]);
     }
+
+    [Test]
+    public void GetTestsInfiniteLoop()
+    {
+        HexGrid grid = new HexGrid();
+        
+        Vector2 fromPlane = new Vector2(-2.31678f, -5.024752f);
+        Vector2 toPlane = new Vector2(-2.599937f, -6.134028f);
+        
+        List<HexCell> cellList = grid.GetCellsForLine(fromPlane, toPlane);
+    }
 }
\ No newline at end of file
diff --git a/tests/NavigationComponentTests.cs b/tests/NavigationComponentTests.cs
index b7c8e8f..b9108e8 100644
--- a/tests/NavigationComponentTests.cs
+++ b/tests/NavigationComponentTests.cs
@@ -28,16 +28,4 @@ public class NavigationComponentTests : TestClass
         _navigationComponent = new NavigationComponent();
         _navigationComponent.TileWorld = _tileWorld;
     }
-
-    [Test]
-    public void SimpleTest()
-    {
-        _tileWorld.HexGrid.AddObstacle(HexCell.FromOffsetCoords(new Vector2 (-4, 7)));
-        
-        Vector3 startPoint = new Vector3(-2.25f, 1.2f, -4.76314f);
-        Vector3 endPoint = new Vector3(-2.533157f, 1.2f, -5.872417f);
-        
-        bool isBlocked = _navigationComponent.CheckSweptTriangleCellCollision(startPoint, endPoint, 0.27f);
-    }
-
 }
\ No newline at end of file