Not stopping until at least 3 line segments drawn is now handled by C…

…loseFieldLine

unity/Assets/Maroon/reusableScripts/FieldLines/FieldLineStopDrawing/CloseFieldLine.cs

@@ -6,22 +6,46 @@ public class CloseFieldLine : MonoBehaviour
 {
     private FieldLine fieldLine;
 
+    [Tooltip("Don't stop drawing until at least this many line segments have been drawn (i.e. the number of StopDrawing calls)")]
+    [SerializeField] private int minLineSegmentCount = 3;
+
+    private int currentLineSegmentIndex;
+
     private void Awake()
     {
         fieldLine = GetComponent<FieldLine>();
         if (fieldLine)
+        {
+            fieldLine.StartDrawing.AddListener(OnStartDrawing);
             fieldLine.stopDrawingCheck = StopDrawing;
+        }
+    }
+
+    private void OnStartDrawing()
+    {
+        currentLineSegmentIndex = -1;
     }
 
+    /// <summary>
+    /// Checks if the FieldLine should stop drawing
+    /// (e.g. because it is close to its start and would otherwise just loop unnecessarily)
+    /// </summary>
+    /// <param name="lineSegmentPosition">The position of the current line segment of the FieldLine</param>
+    /// <returns>True if the FieldLine should stop drawing</returns>
     private bool StopDrawing(Vector3 lineSegmentPosition)
     {
-        var emObj = transform.parent.gameObject;
+        currentLineSegmentIndex++;
 
-        var dist = transform.position;
+        if (currentLineSegmentIndex < minLineSegmentCount)
+        {
+            // Don't stop drawing until minLineSegmentCount has been reached
+            return false;
+        }
 
-        Vector3 fieldLineOffsetStart = fieldLine.transform.TransformPoint(Vector3.zero - fieldLine.originOffset);
-        float lineDistanceToStart = Vector3.Distance(lineSegmentPosition, fieldLineOffsetStart);
+        Vector3 fieldLineStartPosition = fieldLine.transform.TransformPoint(Vector3.zero - fieldLine.originOffset);
+        float lineDistanceToStart = Vector3.Distance(lineSegmentPosition, fieldLineStartPosition);
         bool closeToStart = lineDistanceToStart <= (fieldLine.minLineSegmentLength * 2);
+
         return closeToStart;
     }
 }

unity/Assets/Maroon/reusableScripts/Physics/Electromagnetism/FieldLine.cs

@@ -7,6 +7,8 @@
 
 using UnityEngine;
 using System.Collections.Generic;
+using UnityEngine.Events;
+
 #if UNITY_EDITOR
 using UnityEditor.SceneManagement;
 #endif
@@ -62,6 +64,10 @@ public class FieldLine : MonoBehaviour, IResetObject
         /// </summary>
         private AdvancedLineRenderer _lineRenderer;
 
+        /// <summary>
+        /// Invoked when the FieldLine starts the drawing process.
+        /// </summary>
+        public UnityEvent StartDrawing = new UnityEvent();
         public delegate bool StopDrawingCheck(Vector3 position);
         public StopDrawingCheck stopDrawingCheck;
 
@@ -134,6 +140,8 @@ public void Draw()
             if (!visible || Mathf.Abs(GetFieldStrengthFromEmObj()) * fieldStrengthFactor < 0.05)
                 return;
 
+            StartDrawing?.Invoke();
+
             // Start drawing at originOffset
             int positionIndex = 0;
             Vector3 previousDirection = Vector3.zero;
@@ -152,8 +160,9 @@ public void Draw()
                 if (positionIndex > 3)
                 {
                     // Set line segment length based on how steep the angle to previous direction is
-                    // Except for the first positions (because previousDirection is still Vector3.zero at the beginning,
-                    // and then we also get more accurate result with less jumping around of field lines when moving objects)
+                    // Except for the first positions, because:
+                    //   1. previousDirection is still Vector3.zero at the beginning
+                    //   2. and then we also get more accurate result with less jumping around of field lines when moving objects)
                     float difference = Vector3.Angle(previousDirection, direction);
                     float lerpFactor = 1f - Mathf.Clamp01(difference / maxLineSegmentAngleChangeForLengthAdjustment);
                     lerpFactor = Mathf.Pow(lerpFactor, lineSegmentLengthAdjustmentExponent);
@@ -168,7 +177,7 @@ public void Draw()
                 previousDirection = direction;
 
                 // Check if we should stop drawing
-                if (positionIndex > 3 && stopDrawingCheck != null && stopDrawingCheck(position))
+                if (stopDrawingCheck != null && stopDrawingCheck(position))
                     break;
             }