Trying to search for bestOccludedRelay.
Trying to search for bestOccludedRelay.

--- a/ARMapRenderer.cs
+++ b/ARMapRenderer.cs
@@ -192,73 +192,84 @@
 
 				LineRenderer renderer = this[relay.vessel.id];
 
-				if (relay.CanTransmit())
-				{
-					Vector3d start;
-					Vector3d end;
-
-					renderer.enabled = true;
-
-					if (relay.transmitDistance < relay.nominalTransmitDistance)
+				Vector3d start;
+				Vector3d end;
+
+				renderer.enabled = true;
+
+				if (relay.transmitDistance < relay.nominalTransmitDistance)
+				{
+					renderer.SetColors(Color.green, Color.green);
+				}
+				else
+				{
+					renderer.SetColors(Color.yellow, Color.yellow);
+				}
+
+				start = ScaledSpace.LocalToScaledSpace(relay.vessel.GetWorldPos3D());
+
+				if (relay.KerbinDirect)
+				{
+					if (relay.firstOccludingBody != null && relay.bestOccludedRelay != null)
 					{
-						renderer.SetColors(Color.green, Color.green);
+						end = ScaledSpace.LocalToScaledSpace(relay.bestOccludedRelay.vessel.GetWorldPos3D());
 					}
 					else
 					{
-						renderer.SetColors(Color.yellow, Color.yellow);
-					}
-
-					start = ScaledSpace.LocalToScaledSpace(relay.vessel.GetWorldPos3D());
-
-					if (relay.nearestRelay == null)
-					{
 						end = ScaledSpace.LocalToScaledSpace(AntennaRelay.Kerbin.position);
 					}
-					else
-					{
-						end = ScaledSpace.LocalToScaledSpace(relay.nearestRelay.vessel.GetWorldPos3D());
-					}
-
-					float lineWidth;
-
-					if (MapView.Draw3DLines)
-					{
-						lineWidth = 0.004f * MapView.MapCamera.Distance;
-					}
-					else
-					{
-						lineWidth = 1f;
-
-						start = MapView.MapCamera.camera.WorldToScreenPoint(start);
-						end = MapView.MapCamera.camera.WorldToScreenPoint(end);
-
-						float d = Screen.height / 2f + 0.01f;
-						start.z = start.z >= 0f ? d : -d;
-						end.z = end.z >= 0f ? d : -d;
-					}
-
-					renderer.SetWidth(lineWidth, lineWidth);
-
-					renderer.SetPosition(0, start);
-					renderer.SetPosition(1, end);
-
-					this.vesselFrameCache[relay.vessel.id] = true;
-
-					relay = relay.nearestRelay;
-				}
+				}
+				else
+				{
+					end = ScaledSpace.LocalToScaledSpace(relay.nearestRelay.vessel.GetWorldPos3D());
+				}
+
+				float lineWidth;
+
+				if (MapView.Draw3DLines)
+				{
+					lineWidth = 0.004f * MapView.MapCamera.Distance;
+				}
+				else
+				{
+					lineWidth = 1f;
+
+					start = MapView.MapCamera.camera.WorldToScreenPoint(start);
+					end = MapView.MapCamera.camera.WorldToScreenPoint(end);
+
+					float d = Screen.height / 2f + 0.01f;
+					start.z = start.z >= 0f ? d : -d;
+					end.z = end.z >= 0f ? d : -d;
+				}
+
+				renderer.SetWidth(lineWidth, lineWidth);
+
+				renderer.SetPosition(0, start);
+				renderer.SetPosition(1, end);
+
+				this.vesselFrameCache[relay.vessel.id] = true;
+
+				relay = relay.nearestRelay;
 			}
 			while (relay != null);
 		}
 
 		public void Cleanup()
 		{
-			foreach (LineRenderer lineRenderer in this.vesselLineRenderers.Values)
-			{
-				lineRenderer.enabled = false;
-				GameObject.Destroy(lineRenderer.gameObject);
-			}
-			this.vesselLineRenderers.Clear();
-			this.vesselFrameCache.Clear();
+			if (this.vesselLineRenderers != null && this.vesselLineRenderers.Count > 0)
+			{
+				foreach (LineRenderer lineRenderer in this.vesselLineRenderers.Values)
+				{
+					lineRenderer.enabled = false;
+					GameObject.Destroy(lineRenderer.gameObject);
+				}
+				this.vesselLineRenderers.Clear();
+			}
+
+			if (this.vesselFrameCache != null && this.vesselFrameCache.Count > 0)
+			{
+				this.vesselFrameCache.Clear();
+			}
 		}
 	}
 }

--- a/AntennaRelay.cs
+++ b/AntennaRelay.cs
@@ -31,14 +31,30 @@
 using System.Linq;
 using ToadicusTools;
 
+// @DONE TODO: Retool nearestRelay to always contain the nearest relay, even if out of range.
+// @DONE TODO: Retool CanTransmit to not rely on nearestRelay == null.
+// TODO: Track occluded vessels somehow.
+
 namespace AntennaRange
 {
 	public class AntennaRelay
 	{
 		// We don't have a Bard, so we'll hide Kerbin here.
-		public static CelestialBody Kerbin;
-
-		protected IAntennaRelay _nearestRelayCache;
+		private static CelestialBody _Kerbin;
+		public static CelestialBody Kerbin
+		{
+			get
+			{
+				if (_Kerbin == null && FlightGlobals.ready)
+				{
+					_Kerbin = FlightGlobals.GetHomeBody();
+				}
+
+				return _Kerbin;
+			}
+		}
+
+		private IAntennaRelay _nearestRelayCache;
 		protected IAntennaRelay moduleRef;
 
 		protected System.Diagnostics.Stopwatch searchTimer;
@@ -64,10 +80,11 @@
 		{
 			get
 			{
-				if (this.searchTimer.IsRunning &&
+				if (!this.searchTimer.IsRunning ||
 					this.searchTimer.ElapsedMilliseconds > this.millisecondsBetweenSearches)
 				{
 					this._nearestRelayCache = this.FindNearestRelay();
+
 					this.searchTimer.Restart();
 				}
 
@@ -77,6 +94,12 @@
 			{
 				this._nearestRelayCache = value;
 			}
+		}
+
+		public IAntennaRelay bestOccludedRelay
+		{
+			get;
+			protected set;
 		}
 
 		/// <summary>
@@ -96,19 +119,28 @@
 		{
 			get
 			{
-				this.nearestRelay = this.FindNearestRelay();
-
 				// If there is no available relay nearby...
-				if (this.nearestRelay == null)
-				{
-					// .. return the distance to Kerbin
-					return this.DistanceTo(Kerbin);
-				}
-				else
-				{
-					/// ...otherwise, return the distance to the nearest available relay.
-					return this.DistanceTo(nearestRelay);
-				}
+				// @DONE TODO: Remove nearestRelay == null
+				double kerbinDistance = this.DistanceTo(Kerbin);
+
+				if (this.nearestRelay != null)
+				{
+					double relayDistance = this.DistanceTo(this.nearestRelay);
+
+					// If our nearest relay is nearer than Kerbin, use its distance.
+					if (relayDistance < kerbinDistance)
+					{
+						this.KerbinDirect = false;
+
+						return relayDistance;
+					}
+				}
+
+				this.KerbinDirect = true;
+				
+
+				// .. return the distance to Kerbin
+				return kerbinDistance;
 			}
 		}
 
@@ -139,6 +171,12 @@
 			protected set;
 		}
 
+		public virtual bool KerbinDirect
+		{
+			get;
+			protected set;
+		}
+
 		/// <summary>
 		/// Determines whether this instance can transmit.
 		/// </summary>
@@ -147,20 +185,30 @@
 		{
 			CelestialBody fob = null;
 
-			if (
-				this.transmitDistance > this.maxTransmitDistance ||
-				(
-					ARConfiguration.RequireLineOfSight &&
-					this.nearestRelay == null &&
-					!this.vessel.hasLineOfSightTo(Kerbin, out fob)
+			// @DONE TODO: Remove nearestRelay == null
+			// Because we're correctly falling back to Kerbin in transmitDistance the first test should always fail
+			// when we're out of range of anything, and the second will fail when LOS is blocked (and enforced).
+
+			// If our transmit distance is greater than our maximum range, we can't transmit and it doesn't matter why.
+			if (this.transmitDistance > this.maxTransmitDistance)
+			{
+				this.firstOccludingBody = null;
+				return false;
+			}
+			// ...if we're in range...
+			else
+			{
+				// ...check for LOS problems...
+				if (
+					ARConfiguration.RequireLineOfSight
+					&& this.KerbinDirect &&
+					!this.vessel.hasLineOfSightTo(Kerbin, out fob, ARConfiguration.RadiusRatio)
 				)
-			)
-			{
-				this.firstOccludingBody = fob;
-				return false;
-			}
-			else
-			{
+				{
+					this.firstOccludingBody = fob;
+					return false;
+				}
+
 				this.firstOccludingBody = null;
 				return true;
 			}
@@ -170,9 +218,9 @@
 		/// Finds the nearest relay.
 		/// </summary>
 		/// <returns>The nearest relay or null, if no relays in range.</returns>
-		public IAntennaRelay FindNearestRelay()
-		{
-			if (this.searchTimer.IsRunning && this.searchTimer.ElapsedMilliseconds < this.millisecondsBetweenSearches)
+		private IAntennaRelay FindNearestRelay()
+		{
+			/*if (this.searchTimer.IsRunning && this.searchTimer.ElapsedMilliseconds < this.millisecondsBetweenSearches)
 			{
 				return this.nearestRelay;
 			}
@@ -183,7 +231,7 @@
 				this.searchTimer.Reset();
 			}
 
-			this.searchTimer.Start();
+			this.searchTimer.Start();*/
 
 			Tools.PostDebugMessage(string.Format(
 				"{0}: finding nearest relay for {1} ({2})",
@@ -193,11 +241,14 @@
 			));
 
 			this.firstOccludingBody = null;
+			this.bestOccludedRelay = null;
 
 			// Set this vessel as checked, so that we don't check it again.
 			RelayDatabase.Instance.CheckedVesselsTable[vessel.id] = true;
 
 			double nearestSqrDistance = double.PositiveInfinity;
+			double bestOccludedSqrDistance = double.PositiveInfinity;
+
 			IAntennaRelay _nearestRelay = null;
 
 			/*
@@ -233,37 +284,71 @@
 					continue;
 				}
 
+				// Find the distance from here to the vessel...
+				double potentialSqrDistance = this.sqrDistanceTo(potentialVessel);
+
 				// Skip vessels to which we do not have line of sight.
 				CelestialBody fob = null;
 
-				if (ARConfiguration.RequireLineOfSight &&
-					!this.vessel.hasLineOfSightTo(potentialVessel, out fob, ARConfiguration.RadiusRatio))
+				if (
+					ARConfiguration.RequireLineOfSight &&
+					!this.vessel.hasLineOfSightTo(potentialVessel, out fob, ARConfiguration.RadiusRatio)
+				)
 				{
 					this.firstOccludingBody = fob;
+
 					Tools.PostDebugMessage(
 						this,
-						"Vessel {0} discarded because we do not have line of sight.",
-						potentialVessel.vesselName
+						"Vessel {0} discarded because we do not have line of sight." +
+						"\npotentialSqrDistance: {1}, bestOccludedSqrDistance: {2}, maxTransmitSqrDistance: {3}" +
+						"\npotentialSqrDistance < bestOccludedSqrDistance: {4}" +
+						"\npotentialSqrDistance < (this.maxTransmitDistance * this.maxTransmitDistance): {5}",
+						potentialVessel.vesselName,
+						potentialSqrDistance, bestOccludedSqrDistance, this.maxTransmitDistance * this.maxTransmitDistance,
+						potentialSqrDistance < bestOccludedSqrDistance,
+						potentialSqrDistance < (this.maxTransmitDistance * this.maxTransmitDistance)
 					);
+
+					if (
+						(potentialSqrDistance < bestOccludedSqrDistance) &&
+						(potentialSqrDistance < (this.maxTransmitDistance * this.maxTransmitDistance))
+					)
+					{
+						Tools.PostDebugMessage(
+							this,
+							"Checking {0} relays on {1}.",
+							potentialVessel.GetAntennaRelays().Count(),
+							potentialVessel
+						);
+
+						foreach (IAntennaRelay occludedRelay in potentialVessel.GetAntennaRelays())
+						{
+							Tools.PostDebugMessage(this, "Checking candidate for bestOccludedRelay: {0}" +
+								"\n\tCanTransmit: {1}", occludedRelay, occludedRelay.CanTransmit());
+							if (occludedRelay.CanTransmit())
+							{
+								this.bestOccludedRelay = occludedRelay;
+								this.firstOccludingBody = fob;
+								bestOccludedSqrDistance = potentialSqrDistance;
+								Tools.PostDebugMessage(this, "Found new bestOccludedRelay: {0}" +
+									"\nfirstOccludingBodoy: {1}" +
+									"\nbestOccludedSqrDistance: {2}",
+									occludedRelay,
+									fob,
+									potentialSqrDistance
+								);
+								break;
+							}
+						}
+					}
+
 					continue;
 				}
 
-				this.firstOccludingBody = null;
-
-				// Find the distance from here to the vessel...
-				double potentialSqrDistance = (potentialVessel.GetWorldPos3D() - vessel.GetWorldPos3D()).sqrMagnitude;
-
 				/*
-				 * ...so that we can skip the vessel if it is further away than Kerbin, our transmit distance, or a
-				 * vessel we've already checked.
+				 * ...so that we can skip the vessel if it is further away than a vessel we've already checked.
 				 * */
-				if (
-					potentialSqrDistance > Tools.Min(
-						this.maxTransmitDistance * this.maxTransmitDistance,
-						nearestSqrDistance,
-						this.vessel.sqrDistanceTo(Kerbin)
-					)
-				)
+				if (potentialSqrDistance > nearestSqrDistance)
 				{
 					Tools.PostDebugMessage(
 						this,
@@ -308,13 +393,6 @@
 
 			this.searchTimer = new System.Diagnostics.Stopwatch();
 			this.millisecondsBetweenSearches = 1250;
-
-			// HACK: This might not be safe in all circumstances, but since AntennaRelays are not built until Start,
-			// we hope it is safe enough.
-			if (AntennaRelay.Kerbin == null)
-			{
-				AntennaRelay.Kerbin = FlightGlobals.Bodies.FirstOrDefault(b => b.name == "Kerbin");
-			}
 		}
 	}
 }

--- a/IAntennaRelay.cs
+++ b/IAntennaRelay.cs
@@ -44,6 +44,8 @@
 
 		IAntennaRelay nearestRelay { get; }
 
+		IAntennaRelay bestOccludedRelay { get; }
+
 		/// <summary>
 		/// Gets the distance to the nearest relay or Kerbin, whichever is closer.
 		/// </summary>
@@ -72,6 +74,12 @@
 		bool relayChecked { get; }
 
 		/// <summary>
+		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
+		/// directly with Kerbin.
+		/// </summary>
+		bool KerbinDirect { get; }
+
+		/// <summary>
 		/// Determines whether this instance can transmit.
 		/// </summary>
 		/// <returns><c>true</c> if this instance can transmit; otherwise, <c>false</c>.</returns>

--- a/ModuleLimitedDataTransmitter.cs
+++ b/ModuleLimitedDataTransmitter.cs
@@ -74,8 +74,11 @@
 		[KSPField(isPersistant = false)]
 		public float nominalRange;
 
+		[KSPField(isPersistant = false, guiActive = true, guiName = "Status")]
+		public string UIrelayStatus;
+
 		[KSPField(isPersistant = false, guiActive = true, guiName = "Relay")]
-		public string UIrelayStatus;
+		public string UIrelayTarget;
 
 		[KSPField(isPersistant = false, guiActive = true, guiName = "Transmission Distance")]
 		public string UItransmitDistance;
@@ -135,11 +138,29 @@
 			}
 		}
 
+		public IAntennaRelay bestOccludedRelay
+		{
+			get
+			{
+				if (this.relay == null)
+				{
+					return null;
+				}
+
+				return this.relay.bestOccludedRelay;
+			}
+		}
+
 		// Returns the distance to the nearest relay or Kerbin, whichever is closer.
 		public double transmitDistance
 		{
 			get
 			{
+				if (this.relay == null)
+				{
+					return double.PositiveInfinity;
+				}
+
 				return this.relay.transmitDistance;
 			}
 		}
@@ -155,10 +176,8 @@
 		// Returns the maximum distance this module can transmit
 		public float maxTransmitDistance
 		{
-			get
-			{
-				return Mathf.Sqrt (this.maxPowerFactor) * this.nominalRange;
-			}
+			get;
+			private set;
 		}
 
 		public CelestialBody firstOccludingBody
@@ -238,7 +257,26 @@
 		{
 			get
 			{
-				return this.relay.relayChecked;
+				if (this.relay != null)
+				{
+					return this.relay.relayChecked;
+				}
+
+				// If our relay is null, always return null so we're never checked.
+				return true;
+			}
+		}
+
+		public bool KerbinDirect
+		{
+			get
+			{
+				if (this.relay != null)
+				{
+					return this.relay.KerbinDirect;
+				}
+
+				return false;
 			}
 		}
 
@@ -258,6 +296,7 @@
 
 			this._basepacketSize = base.packetSize;
 			this._basepacketResourceCost = base.packetResourceCost;
+			this.maxTransmitDistance = Mathf.Sqrt(this.maxPowerFactor) * this.nominalRange;
 
 			Tools.PostDebugMessage(string.Format(
 				"{0} loaded:\n" +
@@ -427,7 +466,9 @@
 
 				message.Append("Beginning transmission ");
 
-				if (this.relay.nearestRelay == null)
+				// @DONE TODO: Fix this to fall back to Kerbin if nearestRelay cannot be contacted.
+				// @DONE TODO: Remove nearestRelay == null
+				if (this.KerbinDirect)
 				{
 					message.Append("directly to Kerbin.");
 				}
@@ -545,7 +586,9 @@
 
 				message.Append("Beginning transmission ");
 
-				if (this.relay.nearestRelay == null)
+				// @DONE TODO: Fix this to fall back to Kerbin if nearestRelay cannot be contacted.
+				// @DONE TODO: Remove nearestRelay == null
+				if (this.KerbinDirect)
 				{
 					message.Append("directly to Kerbin.");
 				}
@@ -571,7 +614,7 @@
 			{
 				if (this.CanTransmit())
 				{
-					this.UIrelayStatus = string.Intern("Connected");
+					this.UIrelayStatus = "Connected";
 					this.UItransmitDistance = Tools.MuMech_ToSI(this.transmitDistance) + "m";
 					this.UIpacketSize = Tools.MuMech_ToSI(this.DataRate) + "MiT";
 					this.UIpacketCost = Tools.MuMech_ToSI(this.DataResourceCost) + "E";
@@ -580,7 +623,7 @@
 				{
 					if (this.relay.firstOccludingBody == null)
 					{
-						this.UIrelayStatus = string.Intern("Out of range");
+						this.UIrelayStatus = "Out of range";
 					}
 					else
 					{
@@ -590,6 +633,22 @@
 					this.UIpacketSize = "N/A";
 					this.UIpacketCost = "N/A";
 				}
+
+				if (this.KerbinDirect)
+				{
+					if (this.relay.bestOccludedRelay != null)
+					{
+						this.UIrelayTarget = this.relay.bestOccludedRelay.ToString();
+					}
+					else
+					{
+						this.UIrelayTarget = "Kerbin";
+					}
+				}
+				else
+				{
+					this.UIrelayTarget = this.relay.nearestRelay.ToString();
+				}
 			}
 		}
 
@@ -625,7 +684,7 @@
 		}
 
 		// When debugging, it's nice to have a button that just tells you everything.
-		#if DEBUG
+
 		[KSPEvent (guiName = "Show Debug Info", active = true, guiActive = true)]
 		public void DebugInfo()
 		{
@@ -646,7 +705,9 @@
 				"DataResourceCost: {10}\n" +
 				"TransmitterScore: {11}\n" +
 				"NearestRelay: {12}\n" +
-				"Vessel ID: {13}",
+				"BestOccludedRelay: {13}\n" +
+				"KerbinDirect: {14}\n" +
+				"Vessel ID: {15}",
 				this.name,
 				this._basepacketSize,
 				base.packetSize,
@@ -659,10 +720,13 @@
 				this.DataRate,
 				this.DataResourceCost,
 				ScienceUtil.GetTransmitterScore(this),
-				this.relay.FindNearestRelay(),
+				this.relay.nearestRelay == null ? "null" : this.relay.nearestRelay.ToString(),
+				this.relay.bestOccludedRelay == null ? "null" : this.relay.bestOccludedRelay.ToString(),
+				this.KerbinDirect,
 				this.vessel.id
 				);
-			Tools.PostDebugMessage(msg);
+
+			Tools.PostLogMessage(msg);
 		}
 
 		[KSPEvent (guiName = "Dump Vessels", active = true, guiActive = true)]
@@ -680,11 +744,10 @@
 			Tools.PostDebugMessage(sb.ToString());
 		}
 
-		[KSPEvent (guiName = "Dump RelayDB", active = true, guiActive = true)]
+		/*[KSPEvent (guiName = "Dump RelayDB", active = true, guiActive = true)]
 		public void DumpRelayDB()
 		{
 			RelayDatabase.Instance.Dump();
-		}
-		#endif
+		}*/
 	}
 }

--- a/ProtoAntennaRelay.cs
+++ b/ProtoAntennaRelay.cs
@@ -113,7 +113,7 @@
 		public override string ToString()
 		{
 			return string.Format(
-				"{0} on {1} (proto)",
+				"{0} on {1}",
 				this.title,
 				this.protoPart.pVesselRef.vesselName
 			);

--- a/RelayExtensions.cs
+++ b/RelayExtensions.cs
@@ -68,6 +68,21 @@
 			return relayOne.DistanceTo(relayTwo.vessel);
 		}
 
+		public static double sqrDistanceTo(this AntennaRelay relay, Vessel vessel)
+		{
+			return relay.vessel.sqrDistanceTo(vessel);
+		}
+
+		public static double sqrDistanceTo(this AntennaRelay relay, CelestialBody body)
+		{
+			return relay.vessel.sqrDistanceTo(body);
+		}
+
+		public static double sqrDistanceTo(this AntennaRelay relayOne, AntennaRelay relayTwo)
+		{
+			return relayOne.vessel.sqrDistanceTo(relayTwo.vessel);
+		}
+
 		/// <summary>
 		/// Returns all of the PartModules or ProtoPartModuleSnapshots implementing IAntennaRelay in this Vessel.
 		/// </summary>