VOID_Tools: New CelestialBody tools.
VOID_Tools: New CelestialBody tools.

--- a/VOID_HUDAdvanced.cs
+++ b/VOID_HUDAdvanced.cs
@@ -134,7 +134,7 @@
 					VOID_Data.vesselAngularVelocity.ToSIString(2)
 				);
 
-				if (VOID_Data.stageNominalThrust != 0)
+				if (VOID_Data.stageNominalThrust != 0d)
 				{
 					leftHUD.AppendFormat(
 						string.Intern("Thrust Offset: {0}\n"),
@@ -239,7 +239,7 @@
 				this.leftHUDPos.value = GUI.Window(
 					VOID_Core.Instance.windowID,
 					this.leftHUDPos,
-					this.leftHUDWindow,
+					VOID_Tools.GetWindowHandler(this.leftHUDWindow),
 					GUIContent.none,
 					GUIStyle.none
 				);
@@ -249,7 +249,7 @@
 					this.rightHUDPos.value = GUI.Window(
 						VOID_Core.Instance.windowID,
 						this.rightHUDPos,
-						this.rightHUDWindow,
+						VOID_Tools.GetWindowHandler(this.leftHUDWindow),
 						GUIContent.none,
 						GUIStyle.none
 					);

--- a/VOID_Module.cs
+++ b/VOID_Module.cs
@@ -214,42 +214,7 @@
 		protected float defWidth = 250f;
 		protected float defHeight = 50f;
 
-		public virtual void ModuleWindow(int _)
-		{
-//			if (VOID_Core.Instance.updateTimer - this.lastUpdate > VOID_Core.Instance.updatePeriod) {
-//				foreach (var fieldinfo in this.GetType().GetFields(
-//					BindingFlags.Instance |
-//					BindingFlags.NonPublic |
-//					BindingFlags.Public |
-//					BindingFlags.FlattenHierarchy
-//				))
-//				{
-//					object field = null;
-//
-//					try
-//					{
-//						field = fieldinfo.GetValue (this);
-//					}
-//					catch (NullReferenceException) {
-//						Tools.PostDebugMessage(string.Format(
-//							"{0}: caught NullReferenceException, could not get value for field {1}.",
-//							this.GetType().Name,
-//							fieldinfo.Name
-//						));
-//					}
-//
-//					if (field == null) {
-//						continue;
-//					}
-//
-//					if (typeof(IVOID_DataValue).IsAssignableFrom (field.GetType ())) {
-//						(field as IVOID_DataValue).Refresh ();
-//					}
-//				}
-//
-//				this.lastUpdate = VOID_Core.Instance.updateTimer;
-//			}
-		}
+		public abstract void ModuleWindow(int _);
 
 		public override void DrawGUI()
 		{

--- a/VOID_Orbital.cs
+++ b/VOID_Orbital.cs
@@ -52,8 +52,6 @@
 
 		public override void ModuleWindow(int _)
 		{
-			base.ModuleWindow (_);
-
 			int idx = 0;
 
             GUILayout.BeginVertical();

--- a/VOID_SurfAtmo.cs
+++ b/VOID_SurfAtmo.cs
@@ -49,8 +49,6 @@
 
 		public override void ModuleWindow(int _)
 		{
-			base.ModuleWindow (_);
-
 			int idx = 0;
 
 			GUILayout.BeginVertical();

--- a/VOID_Tools.cs
+++ b/VOID_Tools.cs
@@ -28,12 +28,71 @@
 
 using KSP;
 using System;
+using System.Collections.Generic;
 using UnityEngine;
 
 namespace VOID
 {
 	public static partial class VOID_Tools
 	{
+		#region CelestialBody Utilities
+		public static bool hasAncestor(this CelestialBody bodyA, CelestialBody bodyB)
+		{
+			if (bodyA == null || bodyB == null)
+			{
+				return false;
+			}
+
+			while (bodyA.orbitDriver != null)
+			{
+				if (bodyA.orbit.referenceBody == bodyB)
+				{
+					return true;
+				}
+
+				bodyA = bodyA.orbit.referenceBody;
+			} 
+
+			return false;
+		}
+
+		public static bool NearestRelatedParents(ref CelestialBody bodyA, ref CelestialBody bodyB)
+		{
+			if (bodyA == null || bodyB == null || bodyA.orbitDriver == null || bodyB.orbitDriver == null)
+			{
+				throw new ArgumentException(string.Concat(
+					"CelestialBody::FindRelatedParents: ",
+					"Neither body may be null, and both bodies must have orbits."
+				));
+			}
+
+			CelestialBody a, b;
+
+			a = bodyA;
+
+			while (bodyA.orbitDriver != null)
+			{
+				b = bodyB;
+
+				while (b.orbitDriver != null)
+				{
+					if (a.orbit.referenceBody == b.orbit.referenceBody)
+					{
+						bodyA = a;
+						bodyB = b;
+						return true;
+					}
+
+					b = b.orbit.referenceBody;
+				}
+
+				a = a.orbit.referenceBody;
+			}
+
+			return false;
+		}
+		#endregion
+
 		#region VESSEL_EXTENSIONS_SCIENCE
 		public static CBAttributeMap.MapAttribute GetBiome(this Vessel vessel)
 		{
@@ -256,6 +315,39 @@
 		}
 		#endregion
 
+		private static Dictionary<int, GUI.WindowFunction> functionCache;
+		public static UnityEngine.GUI.WindowFunction GetWindowHandler(Action<int> func)
+		{
+			if (functionCache == null)
+			{
+				functionCache = new Dictionary<int, GUI.WindowFunction>();
+			}
+
+			int hashCode = func.GetHashCode();
+
+			if (!functionCache.ContainsKey(hashCode))
+			{
+				functionCache[hashCode] = delegate (int id)
+				{
+					try
+					{
+						func(id);
+					}
+					catch (ArgumentException ex)
+					{
+						Debug.LogWarning(
+							string.Format("[{0}]: ArgumentException caught during window call.", func.Target.GetType().Name)
+						);
+						#if DEBUG
+						Debug.LogException(ex);
+						#endif
+					}
+				};
+			}
+
+			return functionCache[hashCode];
+		}
+
 		/// <summary>
 		/// Converts the interval given in seconds to a human-friendly
 		/// time period in [years], [days], hours, minutes, and seconds.

--- a/VOID_VesselInfo.cs
+++ b/VOID_VesselInfo.cs
@@ -48,8 +48,6 @@
 
 		public override void ModuleWindow(int _)
 		{
-			base.ModuleWindow (_);
-
 			if ((TimeWarp.WarpMode == TimeWarp.Modes.LOW) || (TimeWarp.CurrentRate <= TimeWarp.MaxPhysicsRate))
 			{
 				SimManager.RequestSimulation();