Index: binaries/data/mods/public/simulation/ai/common-api/shared.js
===================================================================
--- binaries/data/mods/public/simulation/ai/common-api/shared.js
+++ binaries/data/mods/public/simulation/ai/common-api/shared.js
@@ -115,16 +115,6 @@
 	this.accessibility = new m.Accessibility();
 	this.accessibility.init(state, this.terrainAnalyzer);
 
-	// Resource types: ignore = not used for resource maps
-	//                 abundant = abundant resource with small amount each
-	//                 sparse = sparse resource, but huge amount each
-	// The following maps are defined in TerrainAnalysis.js and are used for some building placement (cc, dropsites)
-	// They are updated by checking for create and destroy events for all resources
-	this.normalizationFactor = { "abundant": 50, "sparse": 90 };
-	this.influenceRadius = { "abundant": 36, "sparse": 48 };
-	this.ccInfluenceRadius = { "abundant": 60, "sparse": 120 };
-	this.resourceMaps = {};   // Contains maps showing the density of resources
-	this.ccResourceMaps = {}; // Contains maps showing the density of resources, optimized for CC placement.
 	this.createResourceMaps();
 
 	this.gameState = {};
Index: binaries/data/mods/public/simulation/ai/common-api/terrain-analysis.js
===================================================================
--- binaries/data/mods/public/simulation/ai/common-api/terrain-analysis.js
+++ binaries/data/mods/public/simulation/ai/common-api/terrain-analysis.js
@@ -383,6 +383,17 @@
 /** creates a map of resource density */
 m.SharedScript.prototype.createResourceMaps = function()
 {
+	// Resource types: ignore = not used for resource maps
+	//                 abundant = abundant resource with small amount each
+	//                 sparse = sparse resource, but huge amount each
+	// The following maps are used for some building placement (cc, dropsites)
+	// They are updated by checking for create and destroy events for all resources
+	this.normalizationFactor = { "abundant": 50, "sparse": 90 };
+	this.influenceRadius = { "abundant": 36, "sparse": 48 };
+	this.ccInfluenceRadius = { "abundant": 60, "sparse": 120 };
+	this.resourceMaps = {};   // Contains maps showing the density of resources
+	this.ccResourceMaps = {}; // Contains maps showing the density of resources, optimized for CC placement.
+
 	for (let resource of Resources.GetCodes())
 	{
 		if (!(Resources.GetResource(resource).aiAnalysisInfluenceGroup in this.normalizationFactor))
@@ -396,21 +407,7 @@
 		this.ccResourceMaps[resource] = new m.Map(this, "resource");
 	}
 	for (let ent of this._entities.values())
-	{
-		if (!ent || !ent.position() || !ent.resourceSupplyType())
-			continue;
-		let resource = ent.resourceSupplyType().generic;
-		if (!this.resourceMaps[resource])
-			continue;
-		let cellSize = this.resourceMaps[resource].cellSize;
-		let x = Math.floor(ent.position()[0] / cellSize);
-		let z = Math.floor(ent.position()[1] / cellSize);
-		let grp = Resources.GetResource(resource).aiAnalysisInfluenceGroup;
-		let strength = Math.floor(ent.resourceSupplyMax() / this.normalizationFactor[grp]);
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2, "constant");
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2);
-		this.ccResourceMaps[resource].addInfluence(x, z, this.ccInfluenceRadius[grp] / cellSize, strength, "constant");
-	}
+		this.addEntityToResourceMap(ent);
 };
 
 /**
@@ -420,60 +417,60 @@
  */
 m.SharedScript.prototype.updateResourceMaps = function(events)
 {
-	for (let resource of Resources.GetCodes())
-	{
-		if (!(Resources.GetResource(resource).aiAnalysisInfluenceGroup in this.normalizationFactor))
-			continue;
-		// if there is no resourceMap create one with an influence for everything with that resource
-		if (this.resourceMaps[resource])
-			continue;
-		// We're creating them 8-bit. Things could go above 255 if there are really tons of resources
-		// But at that point the precision is not really important anyway. And it saves memory.
-		this.resourceMaps[resource] = new m.Map(this, "resource");
-		this.ccResourceMaps[resource] = new m.Map(this, "resource");
-	}
-
 	// Look for destroy (or create) events and subtract (or add) the entities original influence from the resourceMap
 	for (let e of events.Destroy)
 	{
 		if (!e.entityObj)
 			continue;
-		let ent = e.entityObj;
-		if (!ent || !ent.position() || !ent.resourceSupplyType())
-			continue;
-		let resource = ent.resourceSupplyType().generic;
-		if (!this.resourceMaps[resource])
-			continue;
-		let cellSize = this.resourceMaps[resource].cellSize;
-		let x = Math.floor(ent.position()[0] / cellSize);
-		let z = Math.floor(ent.position()[1] / cellSize);
-		let grp = Resources.GetResource(resource).aiAnalysisInfluenceGroup;
-		let strength = -Math.floor(ent.resourceSupplyMax() / this.normalizationFactor[grp]);
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2, "constant");
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2);
-		this.ccResourceMaps[resource].addInfluence(x, z, this.ccInfluenceRadius[grp] / cellSize, strength, "constant");
+		this.removeEntityFromResourceMap(e.entityObj);
 	}
 	for (let e of events.Create)
 	{
 		if (!e.entity || !this._entities.has(e.entity))
 			continue;
-		let ent = this._entities.get(e.entity);
-		if (!ent || !ent.position() || !ent.resourceSupplyType())
-			continue;
-		let resource = ent.resourceSupplyType().generic;
-		if (!this.resourceMaps[resource])
-			continue;
-		let cellSize = this.resourceMaps[resource].cellSize;
-		let x = Math.floor(ent.position()[0] / cellSize);
-		let z = Math.floor(ent.position()[1] / cellSize);
-		let grp = Resources.GetResource(resource).aiAnalysisInfluenceGroup;
-		let strength = Math.floor(ent.resourceSupplyMax() / this.normalizationFactor[grp]);
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2, "constant");
-		this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2);
-		this.ccResourceMaps[resource].addInfluence(x, z, this.ccInfluenceRadius[grp] / cellSize, strength, "constant");
+		this.addEntityToResourceMap(this._entities.get(e.entity));
 	}
 };
 
+/**
+ * @param {entity} entity - The entity to add to the resource map.
+ */
+m.SharedScript.prototype.addEntityToResourceMap = function(entity)
+{
+	this.changeEntityInResourceMapHelper(entity, 1);
+};
+
+/**
+ * @param {entity} entity - The entity to remove from the resource map.
+ */
+m.SharedScript.prototype.removeEntityFromResourceMap = function(entity)
+{
+	this.changeEntityInResourceMapHelper(entity, -1);
+};
+
+/**
+ * @param {entity} ent - The entity to add to the resource map.
+ */
+m.SharedScript.prototype.changeEntityInResourceMapHelper = function(ent, multiplication = 1)
+{
+	if (!ent)
+		return;
+	let entPos = ent.position();
+	if (!entPos)
+		return;
+	let resource = ent.resourceSupplyType()?.generic;
+	if (!resource || !this.resourceMaps[resource])
+		return;
+	let cellSize = this.resourceMaps[resource].cellSize;
+	let x = Math.floor(entPos[0] / cellSize);
+	let z = Math.floor(entPos[1] / cellSize);
+	let grp = Resources.GetResource(resource).aiAnalysisInfluenceGroup;
+	let strength = multiplication * Math.floor(ent.resourceSupplyMax() / this.normalizationFactor[grp]);
+	this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2, "constant");
+	this.resourceMaps[resource].addInfluence(x, z, this.influenceRadius[grp] / cellSize, strength/2);
+	this.ccResourceMaps[resource].addInfluence(x, z, this.ccInfluenceRadius[grp] / cellSize, strength, "constant");
+};
+
 return m;
 
 }(API3);