From f5ab6255d018bb1944f8efa0bae84504052aa03f Mon Sep 17 00:00:00 2001
From: alpha123 <alpha123@wildfiregames.com>
Date: Mon, 26 Aug 2013 03:06:08 +0000
Subject: [PATCH] General scrollbar improvements. Patch by Josh. Fixes #2080.

- Don't show the scrollbar when the contents aren't overflowing the
visible area.
- Fix bugs in minimum bar sizing.
- Add capability to set a maximum bar size.
- Correct outdated/incorrect comments.

This was SVN commit r13771.
---
 binaries/data/mods/public/gui/gui.dtd         |   1 +
 .../public/gui/session/selection_details.js   | 638 +++++++++---------
 .../data/mods/public/gui/session/session.xml  |  72 +-
 .../simulation/components/GuiInterface.js     | 289 ++++----
 .../simulation/components/ResourceSupply.js   | 212 ++++--
 .../components/StatisticsTracker.js           |  20 +-
 .../templates/gaia/flora_tree_apple.xml       |   3 +
 .../template_gaia_flora_bush_berry.xml        |  19 +-
 .../templates/template_unit_fauna_fish.xml    |   8 +-
 source/gui/CGUI.cpp                           |   9 +
 source/gui/CGUIScrollBarVertical.cpp          |  60 +-
 source/gui/CGUIScrollBarVertical.h            |   2 +-
 source/gui/IGUIScrollBar.cpp                  |  37 +-
 source/gui/IGUIScrollBar.h                    |  19 +-
 14 files changed, 776 insertions(+), 613 deletions(-)

diff --git a/binaries/data/mods/public/gui/gui.dtd b/binaries/data/mods/public/gui/gui.dtd
index 8b0799ddc3..8c30c22804 100644
--- a/binaries/data/mods/public/gui/gui.dtd
+++ b/binaries/data/mods/public/gui/gui.dtd
@@ -135,6 +135,7 @@
   sprite_bar_vertical_pressed		CDATA #IMPLIED
   sprite_back_vertical			CDATA #IMPLIED
   minimum_bar_size			CDATA #IMPLIED
+  maximum_bar_size			CDATA #IMPLIED
 >
 
 <!--
diff --git a/binaries/data/mods/public/gui/session/selection_details.js b/binaries/data/mods/public/gui/session/selection_details.js
index 2589bc39ab..45dbcad830 100644
--- a/binaries/data/mods/public/gui/session/selection_details.js
+++ b/binaries/data/mods/public/gui/session/selection_details.js
@@ -1,211 +1,221 @@
-function layoutSelectionSingle()
-{
-	getGUIObjectByName("detailsAreaSingle").hidden = false;
-	getGUIObjectByName("detailsAreaMultiple").hidden = true;
-}
-
-function layoutSelectionMultiple()
-{
-	getGUIObjectByName("detailsAreaMultiple").hidden = false;
-	getGUIObjectByName("detailsAreaSingle").hidden = true;
-}
-
-// Fills out information that most entities have
-function displaySingle(entState, template)
-{
-	// Get general unit and player data
-	var specificName = template.name.specific;
-	var genericName = template.name.generic != template.name.specific? template.name.generic : "";
-	// If packed, add that to the generic name (reduces template clutter)
-	if (genericName && template.pack && template.pack.state == "packed")
-		genericName += " -- Packed";
-	var playerState = g_Players[entState.player];
-
-	var civName = g_CivData[playerState.civ].Name;
-	var civEmblem = g_CivData[playerState.civ].Emblem;
-
-	var playerName = playerState.name;
-	var playerColor = playerState.color.r + " " + playerState.color.g + " " + playerState.color.b + " 128";
-
-	// Indicate disconnected players by prefixing their name
-	if (g_Players[entState.player].offline)
-	{
-		playerName = "[OFFLINE] " + playerName;
-	}
-
-	// Rank
-	if (entState.identity && entState.identity.rank && entState.identity.classes)
-	{
-		getGUIObjectByName("rankIcon").tooltip = entState.identity.rank + " Rank";
-		getGUIObjectByName("rankIcon").sprite = getRankIconSprite(entState);					
-		getGUIObjectByName("rankIcon").hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("rankIcon").hidden = true;
-		getGUIObjectByName("rankIcon").tooltip = "";
-	}
-								
-	// Hitpoints
-	if (entState.hitpoints)
-	{
-		var unitHealthBar = getGUIObjectByName("healthBar");
-		var healthSize = unitHealthBar.size;
-		healthSize.rright = 100*Math.max(0, Math.min(1, entState.hitpoints / entState.maxHitpoints));
-		unitHealthBar.size = healthSize;
-
-		var hitpoints = Math.ceil(entState.hitpoints) + " / " + entState.maxHitpoints;
-		getGUIObjectByName("healthStats").caption = hitpoints;
-		getGUIObjectByName("healthSection").hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("healthSection").hidden = true;
-	}
-	
-	// TODO: Stamina
-	var player = Engine.GetPlayerID();
-	if (entState.stamina && (entState.player == player || g_DevSettings.controlAll))
-	{
-		getGUIObjectByName("staminaSection").hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("staminaSection").hidden = true;
-	}
-
-	// Experience
-	if (entState.promotion)
-	{
-		var experienceBar = getGUIObjectByName("experienceBar");
-		var experienceSize = experienceBar.size;
-		experienceSize.rtop = 100 - (100 * Math.max(0, Math.min(1, 1.0 * +entState.promotion.curr / +entState.promotion.req)));
-		experienceBar.size = experienceSize;
- 
-		var experience = "[font=\"serif-bold-13\"]Experience: [/font]" + Math.floor(entState.promotion.curr);
-		if (entState.promotion.curr < entState.promotion.req)
-			experience += " / " + entState.promotion.req;
-		getGUIObjectByName("experience").tooltip = experience;
-		getGUIObjectByName("experience").hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("experience").hidden = true;
-	}
-
-	// Resource stats
-	if (entState.resourceSupply)
-	{
-		var resources = entState.resourceSupply.isInfinite ? "\u221E" :  // Infinity symbol
-						Math.ceil(+entState.resourceSupply.amount) + " / " + entState.resourceSupply.max;
-		var resourceType = entState.resourceSupply.type["generic"];
-		if (resourceType == "treasure")
-			resourceType = entState.resourceSupply.type["specific"];
-
-		var unitResourceBar = getGUIObjectByName("resourceBar");
-		var resourceSize = unitResourceBar.size;
-
-		resourceSize.rright = entState.resourceSupply.isInfinite ? 100 :
-						100 * Math.max(0, Math.min(1, +entState.resourceSupply.amount / +entState.resourceSupply.max));
-		unitResourceBar.size = resourceSize;
-		getGUIObjectByName("resourceLabel").caption = toTitleCase(resourceType) + ":";
-		getGUIObjectByName("resourceStats").caption = resources;
-
-		if (entState.hitpoints)
-			getGUIObjectByName("resourceSection").size = getGUIObjectByName("staminaSection").size;
-		else
-			getGUIObjectByName("resourceSection").size = getGUIObjectByName("healthSection").size;
-
-		getGUIObjectByName("resourceSection").hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("resourceSection").hidden = true;
-	}
-
-	// Resource carrying
-	if (entState.resourceCarrying && entState.resourceCarrying.length)
-	{
-		// We should only be carrying one resource type at once, so just display the first
-		var carried = entState.resourceCarrying[0];
-
-		getGUIObjectByName("resourceCarryingIcon").hidden = false;
-		getGUIObjectByName("resourceCarryingText").hidden = false;
-		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/resources/"+carried.type+".png";
-		getGUIObjectByName("resourceCarryingText").caption = carried.amount + " / " + carried.max;
-		getGUIObjectByName("resourceCarryingIcon").tooltip = "";
-	}
-	// Use the same indicators for traders
-	else if (entState.trader && entState.trader.goods.amount)
-	{
-		getGUIObjectByName("resourceCarryingIcon").hidden = false;
-		getGUIObjectByName("resourceCarryingText").hidden = false;
-		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/resources/"+entState.trader.goods.type+".png";
-		var totalGain = entState.trader.goods.amount.traderGain;
-		if (entState.trader.goods.amount.market1Gain)
-			totalGain += entState.trader.goods.amount.market1Gain;
-		if (entState.trader.goods.amount.market2Gain)
-			totalGain += entState.trader.goods.amount.market2Gain;
-		getGUIObjectByName("resourceCarryingText").caption = totalGain;
-		getGUIObjectByName("resourceCarryingIcon").tooltip = "Gain: " + getTradingTooltip(entState.trader.goods.amount);
-	}
-	// And for number of workers
-	else if (entState.foundation)
-	{
-		getGUIObjectByName("resourceCarryingIcon").hidden = false;
-		getGUIObjectByName("resourceCarryingText").hidden = false;
-		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/repair.png";
-		getGUIObjectByName("resourceCarryingText").caption = entState.foundation.numBuilders + "    ";
-		getGUIObjectByName("resourceCarryingIcon").tooltip = "Number of builders";
-	}
-	else if (entState.resourceSupply && (!entState.resourceSupply.killBeforeGather || !entState.hitpoints))
-	{
-		getGUIObjectByName("resourceCarryingIcon").hidden = false;
-		getGUIObjectByName("resourceCarryingText").hidden = false;
-		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/repair.png";
-		getGUIObjectByName("resourceCarryingText").caption = entState.resourceSupply.gatherers.length + " / " + entState.resourceSupply.maxGatherers + "    ";
-		getGUIObjectByName("resourceCarryingIcon").tooltip = "Current/max gatherers";
-	}
-	else
-	{
-		getGUIObjectByName("resourceCarryingIcon").hidden = true;
-		getGUIObjectByName("resourceCarryingText").hidden = true;
-	}
-
-	// Set Player details
-	getGUIObjectByName("specific").caption = specificName;
-	getGUIObjectByName("player").caption = playerName;
-	getGUIObjectByName("playerColorBackground").sprite = "colour: " + playerColor;
-	
-	if (genericName)
-	{
-		getGUIObjectByName("generic").caption = "(" + genericName + ")";
-	}
-	else
-	{
-		getGUIObjectByName("generic").caption = "";
-
-	}
-
-	if ("Gaia" != civName)
-	{
-		getGUIObjectByName("playerCivIcon").sprite = "stretched:grayscale:" + civEmblem;
-		getGUIObjectByName("player").tooltip = civName;
-	}
-	else
-	{
-		getGUIObjectByName("playerCivIcon").sprite = "";
-		getGUIObjectByName("player").tooltip = "";
-	}
-
-	// Icon image
-	if (template.icon)
-	{
-		getGUIObjectByName("icon").sprite = "stretched:session/portraits/" + template.icon;
-	}
-	else
-	{
-		// TODO: we should require all entities to have icons, so this case never occurs
+function layoutSelectionSingle()
+{
+	getGUIObjectByName("detailsAreaSingle").hidden = false;
+	getGUIObjectByName("detailsAreaMultiple").hidden = true;
+}
+
+function layoutSelectionMultiple()
+{
+	getGUIObjectByName("detailsAreaMultiple").hidden = false;
+	getGUIObjectByName("detailsAreaSingle").hidden = true;
+}
+
+// Fills out information that most entities have
+function displaySingle(entState, template)
+{
+	// Get general unit and player data
+	var specificName = template.name.specific;
+	var genericName = template.name.generic != template.name.specific? template.name.generic : "";
+	// If packed, add that to the generic name (reduces template clutter)
+	if (genericName && template.pack && template.pack.state == "packed")
+		genericName += " -- Packed";
+	var playerState = g_Players[entState.player];
+
+	var civName = g_CivData[playerState.civ].Name;
+	var civEmblem = g_CivData[playerState.civ].Emblem;
+
+	var playerName = playerState.name;
+	var playerColor = playerState.color.r + " " + playerState.color.g + " " + playerState.color.b + " 128";
+
+	// Indicate disconnected players by prefixing their name
+	if (g_Players[entState.player].offline)
+	{
+		playerName = "[OFFLINE] " + playerName;
+	}
+
+	// Rank
+	if (entState.identity && entState.identity.rank && entState.identity.classes)
+	{
+		getGUIObjectByName("rankIcon").tooltip = entState.identity.rank + " Rank";
+		getGUIObjectByName("rankIcon").sprite = getRankIconSprite(entState);
+		getGUIObjectByName("rankIcon").hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("rankIcon").hidden = true;
+		getGUIObjectByName("rankIcon").tooltip = "";
+	}
+
+	// Hitpoints
+	if (entState.hitpoints)
+	{
+		var unitHealthBar = getGUIObjectByName("healthBar");
+		var healthSize = unitHealthBar.size;
+		healthSize.rright = 100*Math.max(0, Math.min(1, entState.hitpoints / entState.maxHitpoints));
+		unitHealthBar.size = healthSize;
+
+		var hitpoints = Math.ceil(entState.hitpoints) + " / " + entState.maxHitpoints;
+		getGUIObjectByName("healthStats").caption = hitpoints;
+		getGUIObjectByName("healthSection").hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("healthSection").hidden = true;
+	}
+
+	// TODO: Stamina
+	var player = Engine.GetPlayerID();
+	if (entState.stamina && (entState.player == player || g_DevSettings.controlAll))
+	{
+		getGUIObjectByName("staminaSection").hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("staminaSection").hidden = true;
+	}
+
+	// Experience
+	if (entState.promotion)
+	{
+		var experienceBar = getGUIObjectByName("experienceBar");
+		var experienceSize = experienceBar.size;
+		experienceSize.rtop = 100 - (100 * Math.max(0, Math.min(1, 1.0 * +entState.promotion.curr / +entState.promotion.req)));
+		experienceBar.size = experienceSize;
+
+		var experience = "[font=\"serif-bold-13\"]Experience: [/font]" + Math.floor(entState.promotion.curr);
+		if (entState.promotion.curr < entState.promotion.req)
+			experience += " / " + entState.promotion.req;
+		getGUIObjectByName("experience").tooltip = experience;
+		getGUIObjectByName("experience").hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("experience").hidden = true;
+	}
+
+	// Resource stats
+	if (entState.resourceSupply)
+	{
+		var resources = entState.resourceSupply.isInfinite ? "\u221E" :  // Infinity symbol
+						Math.ceil(+entState.resourceSupply.amount) + " / " + entState.resourceSupply.max;
+		var resourceType = entState.resourceSupply.type["generic"];
+		if (resourceType == "treasure")
+			resourceType = entState.resourceSupply.type["specific"];
+
+		var unitResourceBar = getGUIObjectByName("resourceBar");
+		var resourceSize = unitResourceBar.size;
+
+		resourceSize.rright = entState.resourceSupply.isInfinite ? 100 :
+						100 * Math.max(0, Math.min(1, +entState.resourceSupply.amount / +entState.resourceSupply.max));
+		unitResourceBar.size = resourceSize;
+		getGUIObjectByName("resourceLabel").caption = toTitleCase(resourceType) + ":";
+		getGUIObjectByName("resourceStats").caption = resources;
+
+		if (entState.hitpoints)
+			getGUIObjectByName("resourceSection").size = getGUIObjectByName("staminaSection").size;
+		else
+			getGUIObjectByName("resourceSection").size = getGUIObjectByName("healthSection").size;
+
+		getGUIObjectByName("resourceSection").hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("resourceSection").hidden = true;
+	}
+
+    var activeResource = entState.resourceSupply && (!entState.resourceSupply.killBeforeGather || !entState.hitpoints)
+    getGUIObjectByName("resourceThroughputIcon").hidden = !activeResource;
+    getGUIObjectByName("resourceThroughputText").hidden = !activeResource;
+
+	// Resource carrying
+	if (entState.resourceCarrying && entState.resourceCarrying.length)
+	{
+		// We should only be carrying one resource type at once, so just display the first
+		var carried = entState.resourceCarrying[0];
+
+		getGUIObjectByName("resourceCarryingIcon").hidden = false;
+		getGUIObjectByName("resourceCarryingText").hidden = false;
+		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/resources/"+carried.type+".png";
+		getGUIObjectByName("resourceCarryingText").caption = carried.amount + " / " + carried.max;
+		getGUIObjectByName("resourceCarryingIcon").tooltip = "";
+	}
+	// Use the same indicators for traders
+	else if (entState.trader && entState.trader.goods.amount)
+	{
+		getGUIObjectByName("resourceCarryingIcon").hidden = false;
+		getGUIObjectByName("resourceCarryingText").hidden = false;
+		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/resources/"+entState.trader.goods.type+".png";
+		var totalGain = entState.trader.goods.amount.traderGain;
+		if (entState.trader.goods.amount.market1Gain)
+			totalGain += entState.trader.goods.amount.market1Gain;
+		if (entState.trader.goods.amount.market2Gain)
+			totalGain += entState.trader.goods.amount.market2Gain;
+		getGUIObjectByName("resourceCarryingText").caption = totalGain;
+		getGUIObjectByName("resourceCarryingIcon").tooltip = "Gain: " + getTradingTooltip(entState.trader.goods.amount);
+	}
+	else if (entState.foundation)
+	{
+        // Number of builders
+		getGUIObjectByName("resourceCarryingIcon").hidden = false;
+		getGUIObjectByName("resourceCarryingText").hidden = false;
+		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/repair.png";
+		getGUIObjectByName("resourceCarryingText").caption = entState.foundation.numBuilders + "    ";
+		getGUIObjectByName("resourceCarryingIcon").tooltip = "Number of builders";
+	}
+	else if (activeResource)
+	{
+        // Number of gatherers
+		getGUIObjectByName("resourceCarryingIcon").hidden = false;
+		getGUIObjectByName("resourceCarryingText").hidden = false;
+		getGUIObjectByName("resourceCarryingIcon").sprite = "stretched:session/icons/repair.png";
+		getGUIObjectByName("resourceCarryingText").caption = entState.resourceSupply.gatherers.length + " / " + entState.resourceSupply.maxGatherers + "    ";
+		getGUIObjectByName("resourceCarryingIcon").tooltip = "Current/max gatherers";
+
+        // Current total resource output in resources/second
+        getGUIObjectByName("resourceThroughputIcon").sprite = "stretched:session/icons/production.png";
+        getGUIObjectByName("resourceThroughputText").caption = entState.resourceSupply.throughput.toFixed(2);
+        getGUIObjectByName("resourceThroughputIcon").tooltip = "Currently producing " + entState.resourceSupply.throughput.toFixed(2) + " resources/second.";
+	}
+	else
+	{
+		getGUIObjectByName("resourceCarryingIcon").hidden = true;
+		getGUIObjectByName("resourceCarryingText").hidden = true;
+	}
+
+	// Set Player details
+	getGUIObjectByName("specific").caption = specificName;
+	getGUIObjectByName("player").caption = playerName;
+	getGUIObjectByName("playerColorBackground").sprite = "colour: " + playerColor;
+
+	if (genericName)
+	{
+		getGUIObjectByName("generic").caption = "(" + genericName + ")";
+	}
+	else
+	{
+		getGUIObjectByName("generic").caption = "";
+
+	}
+
+	if ("Gaia" != civName)
+	{
+		getGUIObjectByName("playerCivIcon").sprite = "stretched:grayscale:" + civEmblem;
+		getGUIObjectByName("player").tooltip = civName;
+	}
+	else
+	{
+		getGUIObjectByName("playerCivIcon").sprite = "";
+		getGUIObjectByName("player").tooltip = "";
+	}
+
+	// Icon image
+	if (template.icon)
+	{
+		getGUIObjectByName("icon").sprite = "stretched:session/portraits/" + template.icon;
+	}
+	else
+	{
+		// TODO: we should require all entities to have icons, so this case never occurs
 		getGUIObjectByName("icon").sprite = "bkFillBlack";
 	}
 
@@ -221,11 +231,11 @@ function displaySingle(entState, template)
 		{
 			var realRange = entState.attack.elevationAdaptedRange;
 			var range =  entState.attack.maxRange;
-			attack += ", [font=\"serif-bold-13\"]Range:[/font] " + 
+			attack += ", [font=\"serif-bold-13\"]Range:[/font] " +
 				Math.round(range/4);
 
 			if (Math.round((realRange - range)/4) > 0)
-			{ 
+			{
 				attack += " (+" + Math.round((realRange - range)/4) + ")";
 			}
 			else if (Math.round((realRange - range)/4) < 0)
@@ -235,113 +245,113 @@ function displaySingle(entState, template)
 
 		}
 	}
-	
+
 	getGUIObjectByName("attackAndArmorStats").tooltip = attack + "\n[font=\"serif-bold-13\"]Armor:[/font] " + armorTypeDetails(entState.armour);
 
 	// Icon Tooltip
 	var iconTooltip = "";
 
 	if (genericName)
-		iconTooltip = "[font=\"serif-bold-16\"]" + genericName + "[/font]";
-
-	if (template.tooltip)
-		iconTooltip += "\n[font=\"serif-13\"]" + template.tooltip + "[/font]";
-
-	getGUIObjectByName("iconBorder").tooltip = iconTooltip;
-
-	// Unhide Details Area
-	getGUIObjectByName("detailsAreaSingle").hidden = false;
-	getGUIObjectByName("detailsAreaMultiple").hidden = true;
-}
-
-// Fills out information for multiple entities
-function displayMultiple(selection, template)
-{
-	var averageHealth = 0;
-	var maxHealth = 0;
-
-	for (var i = 0; i < selection.length; i++)
-	{
-		var entState = GetEntityState(selection[i])
-		if (entState)
-		{
-			if (entState.hitpoints)
-			{
-				averageHealth += entState.hitpoints;
-				maxHealth += entState.maxHitpoints;
-			}
-		}
-	}
-
-	if (averageHealth > 0)
-	{
-		var unitHealthBar = getGUIObjectByName("healthBarMultiple");
-		var healthSize = unitHealthBar.size;	
-		healthSize.rtop = 100-100*Math.max(0, Math.min(1, averageHealth / maxHealth));
-		unitHealthBar.size = healthSize;
-
-		var hitpoints = "[font=\"serif-bold-13\"]Hitpoints [/font]" + averageHealth + " / " + maxHealth;
-		var healthMultiple = getGUIObjectByName("healthMultiple");
-		healthMultiple.tooltip = hitpoints;
-		healthMultiple.hidden = false;
-	}
-	else
-	{
-		getGUIObjectByName("healthMultiple").hidden = true;
-	}
-	
-	// TODO: Stamina
-	// getGUIObjectByName("staminaBarMultiple");
-
-	getGUIObjectByName("numberOfUnits").caption = selection.length;
-
-	// Unhide Details Area
-	getGUIObjectByName("detailsAreaMultiple").hidden = false;
-	getGUIObjectByName("detailsAreaSingle").hidden = true;
-}
-
-// Updates middle entity Selection Details Panel
-function updateSelectionDetails()
-{
-	var supplementalDetailsPanel = getGUIObjectByName("supplementalSelectionDetails");
-	var detailsPanel = getGUIObjectByName("selectionDetails");
-	var commandsPanel = getGUIObjectByName("unitCommands");
-
-	g_Selection.update();
-	var selection = g_Selection.toList();
-	
-	if (selection.length == 0)
-	{
-		getGUIObjectByName("detailsAreaMultiple").hidden = true;
-		getGUIObjectByName("detailsAreaSingle").hidden = true;
-		hideUnitCommands();
-	
-		supplementalDetailsPanel.hidden = true;
-		detailsPanel.hidden = true;
-		commandsPanel.hidden = true;
-		return;
-	}
-
-	/* If the unit has no data (e.g. it was killed), don't try displaying any
-	 data for it. (TODO: it should probably be removed from the selection too;
-	 also need to handle multi-unit selections) */
-	var entState = GetEntityState(selection[0]);
-	if (!entState)
-		return;
-
-	var template = GetTemplateData(entState.template);
-
-	// Fill out general info and display it
-	if (selection.length == 1)
-		displaySingle(entState, template);
-	else
-		displayMultiple(selection, template);
-
-	// Show Panels
-	supplementalDetailsPanel.hidden = false;
-	detailsPanel.hidden = false;
-	commandsPanel.hidden = false;
-
-	// Fill out commands panel for specific unit selected (or first unit of primary group)
-	updateUnitCommands(entState, supplementalDetailsPanel, commandsPanel, selection);
-}
+		iconTooltip = "[font=\"serif-bold-16\"]" + genericName + "[/font]";
+
+	if (template.tooltip)
+		iconTooltip += "\n[font=\"serif-13\"]" + template.tooltip + "[/font]";
+
+	getGUIObjectByName("iconBorder").tooltip = iconTooltip;
+
+	// Unhide Details Area
+	getGUIObjectByName("detailsAreaSingle").hidden = false;
+	getGUIObjectByName("detailsAreaMultiple").hidden = true;
+}
+
+// Fills out information for multiple entities
+function displayMultiple(selection, template)
+{
+	var averageHealth = 0;
+	var maxHealth = 0;
+
+	for (var i = 0; i < selection.length; i++)
+	{
+		var entState = GetEntityState(selection[i])
+		if (entState)
+		{
+			if (entState.hitpoints)
+			{
+				averageHealth += entState.hitpoints;
+				maxHealth += entState.maxHitpoints;
+			}
+		}
+	}
+
+	if (averageHealth > 0)
+	{
+		var unitHealthBar = getGUIObjectByName("healthBarMultiple");
+		var healthSize = unitHealthBar.size;
+		healthSize.rtop = 100-100*Math.max(0, Math.min(1, averageHealth / maxHealth));
+		unitHealthBar.size = healthSize;
+
+		var hitpoints = "[font=\"serif-bold-13\"]Hitpoints [/font]" + averageHealth + " / " + maxHealth;
+		var healthMultiple = getGUIObjectByName("healthMultiple");
+		healthMultiple.tooltip = hitpoints;
+		healthMultiple.hidden = false;
+	}
+	else
+	{
+		getGUIObjectByName("healthMultiple").hidden = true;
+	}
+
+	// TODO: Stamina
+	// getGUIObjectByName("staminaBarMultiple");
+
+	getGUIObjectByName("numberOfUnits").caption = selection.length;
+
+	// Unhide Details Area
+	getGUIObjectByName("detailsAreaMultiple").hidden = false;
+	getGUIObjectByName("detailsAreaSingle").hidden = true;
+}
+
+// Updates middle entity Selection Details Panel
+function updateSelectionDetails()
+{
+	var supplementalDetailsPanel = getGUIObjectByName("supplementalSelectionDetails");
+	var detailsPanel = getGUIObjectByName("selectionDetails");
+	var commandsPanel = getGUIObjectByName("unitCommands");
+
+	g_Selection.update();
+	var selection = g_Selection.toList();
+
+	if (selection.length == 0)
+	{
+		getGUIObjectByName("detailsAreaMultiple").hidden = true;
+		getGUIObjectByName("detailsAreaSingle").hidden = true;
+		hideUnitCommands();
+
+		supplementalDetailsPanel.hidden = true;
+		detailsPanel.hidden = true;
+		commandsPanel.hidden = true;
+		return;
+	}
+
+	/* If the unit has no data (e.g. it was killed), don't try displaying any
+	 data for it. (TODO: it should probably be removed from the selection too;
+	 also need to handle multi-unit selections) */
+	var entState = GetEntityState(selection[0]);
+	if (!entState)
+		return;
+
+	var template = GetTemplateData(entState.template);
+
+	// Fill out general info and display it
+	if (selection.length == 1)
+		displaySingle(entState, template);
+	else
+		displayMultiple(selection, template);
+
+	// Show Panels
+	supplementalDetailsPanel.hidden = false;
+	detailsPanel.hidden = false;
+	commandsPanel.hidden = false;
+
+	// Fill out commands panel for specific unit selected (or first unit of primary group)
+	updateUnitCommands(entState, supplementalDetailsPanel, commandsPanel, selection);
+}
diff --git a/binaries/data/mods/public/gui/session/session.xml b/binaries/data/mods/public/gui/session/session.xml
index f3e68cd6a9..2c136c0be2 100644
--- a/binaries/data/mods/public/gui/session/session.xml
+++ b/binaries/data/mods/public/gui/session/session.xml
@@ -177,12 +177,12 @@
 	<object hotkey="camera.jump.set.10">
 		<action on="Press">setJumpCamera(10);</action>
 	</object>
-	
+
 	<!-- Stop the selected units -->
 	<object hotkey="session.stop">
 	    <action on="Press">stopUnits(g_Selection.toList());</action>
 	</object>
-	
+
 	<!-- queue first unit in the training queue  -->
 	<object hotkey="session.queueunit.1">
 	    <action on="Press">addTrainingByPosition(0);</action>
@@ -202,7 +202,7 @@
 	<object hotkey="session.queueunit.4">
 	    <action on="Press">addTrainingByPosition(3);</action>
 	</object>
-	
+
 	<!-- queue 5th unit in the training queue  -->
 	<object hotkey="session.queueunit.5">
 	    <action on="Press">addTrainingByPosition(4);</action>
@@ -315,7 +315,7 @@
 	<!-- ================================  ================================ -->
 	<!-- Time elapsed counter -->
 	<!-- ================================  ================================ -->
-	
+
 	<object size="100%-120 45 100%-10 65" type="text" name="timeElapsedCounter" style="SettingsText" hotkey="timeelapsedcounter.toggle" hidden="true">
 	    <action on="Press">this.hidden = !this.hidden;</action>
 	</object>
@@ -442,7 +442,7 @@
 			z="200"
 			>
 			<object type="text" style="TitleText" size="50%-96 -16 50%+96 16">Settings</object>
-			
+
 			<object style="TranslucentPanelThinBorder"
 				type="image"
 				size="32 32 100%-32 100%-70"
@@ -453,21 +453,21 @@
 					<action on="Load">if (renderer.shadows) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.shadows = this.checked;</action>
 				</object>
-				
+
 				<!-- Settings / Shadow PCF -->
 				<object size="0 35 100%-80 60" type="text" style="RightLabelText" ghost="true">Enable Shadow Filtering</object>
 				<object name="shadowPCFCheckbox" size="100%-56 40 100%-30 65" type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.shadowPCF) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.shadowPCF = this.checked;</action>
 				</object>
-				
+
 				<!-- Settings / Water Normals -->
 				<object size="0 60 100%-80 85" type="text" style="RightLabelText" ghost="true">Water - HQ Waviness</object>
 				<object name="waterNormalCheckox" size="100%-56 65 100%-30 90"  type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.waternormal) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.waternormal = this.checked;</action>
 				</object>
-				
+
 				<!-- Settings / Real Depth -->
 				<object size="0 85 100%-80 110" type="text" style="RightLabelText" ghost="true">Water - Use Actual Depth</object>
 				<object name="waterRealDepthCheckbox" size="100%-56 90 100%-30 115"  type="checkbox" style="StoneCrossBox" checked="true">
@@ -481,28 +481,28 @@
 					<action on="Load">if (renderer.waterreflection) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.waterreflection = this.checked; </action>
 				</object>
-				
+
 				<!-- Settings / Refraction -->
 				<object size="0 135 100%-80 160" type="text" style="RightLabelText" ghost="true">Water - Enable Refraction</object>
 				<object name="waterRefractionCheckbox" size="100%-56 140 100%-30 165"  type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.waterrefraction) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.waterrefraction = this.checked; </action>
 				</object>
-				
+
 				<!-- Settings / Foam -->
 				<object size="0 160 100%-80 185" type="text" style="RightLabelText" ghost="true">Water - Enable Shore Foam</object>
 				<object name="waterFoamCheckbox" size="100%-56 165 100%-30 190"  type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.waterfoam) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.waterfoam = this.checked; </action>
 				</object>
-				
+
 				<!-- Settings / Waves -->
 				<object size="0 185 100%-80 210" type="text" style="RightLabelText" ghost="true">Water - Enable Shore Waves</object>
 				<object name="waterCoastalWavesCheckbox" size="100%-56 190 100%-30 215"  type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.watercoastalwaves) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.watercoastalwaves = this.checked; </action>
 				</object>
-				
+
 				<!-- Settings / Shadows -->
 				<object size="0 210 100%-80 235" type="text" style="RightLabelText" ghost="true">Water - Use Surface Shadows</object>
 				<object name="waterShadowsCheckbox" size="100%-56 215 100%-30 240"  type="checkbox" style="StoneCrossBox" checked="true">
@@ -516,27 +516,27 @@
 					<action on="Load">if (renderer.particles) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.particles = this.checked;</action>
 				</object>
-				
+
 				<!-- Settings / Unit Silhouettes -->
 				<object size="0 260 100%-80 285" type="text" style="RightLabelText" ghost="true">Enable Unit Silhouettes</object>
 				<object name="silhouettesCheckbox" size="100%-56 265 100%-30 290" type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Load">if (renderer.silhouettes) this.checked = true; else this.checked = false;</action>
 					<action on="Press">renderer.silhouettes = this.checked;</action>
 				</object>
-				
+
 				<!-- Settings / Music-->
 				<object size="0 285 100%-80 310" type="text" style="RightLabelText" ghost="true">Enable Music</object>
 				<object name="musicCheckbox" size="100%-56 290 100%-30 315" type="checkbox" style="StoneCrossBox" checked="true">
 					<action on="Press">if (this.checked) global.music.start(); else global.music.stop();</action>
 				</object>
-				
+
 				<!-- Settings / Dev Overlay -->
 				<object size="0 310 100%-80 335" type="text" style="RightLabelText" ghost="true">Developer Overlay</object>
 				<object name="developerOverlayCheckbox" size="100%-56 315 100%-30 340" type="checkbox" style="StoneCrossBox" checked="false">
 					<action on="Press">toggleDeveloperOverlay();</action>
 				</object>
 			</object>
-			
+
 			<!-- Close button -->
 			<object type="button"
 				style="StoneButton"
@@ -640,7 +640,7 @@
 	    </object>
 
 		<object size="100%-348 40 100%-198 65" name="gameSpeed" type="dropdown" buffer_zone="5" style="StoneDropDown" hidden="true" tooltip="Choose game speed" tooltip_style="sessionToolTip"/>
-		
+
 	    <!-- ================================  ================================ -->
 	    <!-- Diplomacy Button -->
 	    <!-- ================================  ================================ -->
@@ -790,12 +790,12 @@
 	    name="unitHeroPanel"
 	    size="0 36 50 86"
 	>
-		<object name="unitHeroButton" size="0 0 50 50" type="button" hidden="false" style="iconButton" 
+		<object name="unitHeroButton" size="0 0 50 50" type="button" hidden="false" style="iconButton"
 			tooltip_style="sessionToolTip" tooltip="Attack and Armor">
 			<object name="unitHeroImage" size="5 5 100%-5 100%-5" type="image" ghost="true"/>
 		</object>
 	</object>
-	
+
 	<!-- ================================  ================================ -->
 	<!-- Unit Selection Groups -->
 	<!-- ================================  ================================ -->
@@ -896,7 +896,7 @@
 		    </object>
 		</object>
 
-		<object name="unitBarterPanel" 
+		<object name="unitBarterPanel"
 			size="6 36 100% 100%"
 			hidden="true"
 		>
@@ -950,10 +950,10 @@
 	    >
 		<!-- Unit details for Single Unit -->
 		<object size="50%-112 0 50%+112 100%" name="detailsAreaSingle">
-		    
+
 		    <!-- Stats Bars -->
 		    <object size= "2 0 100%-2 98" type="image" tooltip_style="sessionToolTip">
-			
+
 			<object size="0 8 100% 60" type="image" sprite="edgedPanelShader">
 			    <!-- Health bar -->
 			    <object size="88 0 100% 24" name="healthSection">
@@ -991,21 +991,25 @@
 				</object>
 			    </object>
 			</object>
-			
+
 			<object size="0 60 100% 96" type="image" sprite="edgedPanelShader">
 			    <!-- Attack and Armor -->
 			    <object size="90 -2 126 34" name="attackAndArmorStats" type="image" sprite="stretched:session/icons/stances/defensive.png" tooltip="Attack and Armor" tooltip_style="sessionToolTip"/>
 
 			    <!-- Resource carrying icon/counter -->
 			    <!-- Used also for number of gatherers/builders -->
-			    <object size="100%-98 -2 100%-28 34" type="text" name="resourceCarryingText" style="CarryingTextRight"/>
-			    <object size="100%-36 -2 100% 34" type="image" name="resourceCarryingIcon" tooltip_style="sessionToolTip"/>
+			    <object size="100%-78 -2 100%-84 34" type="text" name="resourceCarryingText" style="CarryingTextRight"/>
+			    <object size="100%-36 -2 100%-56 34" type="image" name="resourceCarryingIcon" tooltip_style="sessionToolTip"/>
+
+				<!-- Throughput of this resource in resources/second -->
+				<object size="100%-10 -2 100%-28 34" type="text" name="resourceThroughputText" style="CarryingTextRight"/>
+				<object size="100%-5 -2 100% 34" type="text" name="resourceThroughputIcon" tooltip_style="sessionToolTip"/>
 			</object>
-			
+
 			<!-- Big unit icon -->
 			<object size="-8 -8 88 88" type="image" name="iconBorder" sprite="iconBorder" tooltip_style="sessionToolTip">
 			    <object size="1 1 100%-1 100%-1" type="image" name="icon" ghost="true"/>
-			
+
 			    <!-- Experience bar -->
 			    <object size="2 2 6 100%-2" type="image" name="experience" tooltip="Experience" tooltip_style="sessionToolTip">
 				<object type="image" sprite="barBorder" ghost="true" size="-1 -1 100%+1 100%+1"/>
@@ -1013,18 +1017,18 @@
 				<object type="image" sprite="experienceForeground" ghost="true" name="experienceBar"/>
 				<object type="image" sprite="statsBarShaderVertical" ghost="true"/>
 			    </object>
-			
+
 			    <object z="20" size="4 4 20 20" name="rankIcon" type="image" tooltip="Rank" tooltip_style="sessionToolTip"/>
 			</object>
 		    </object>
-		    
+
 		    <!-- Names (this must come before the attack and armor icon to avoid clipping issues) -->
 		    <object size="2 96 100%-2 100%-36" name="statsArea" type="image" sprite="edgedPanelShader">
-			
+
 			<!-- These images are used to clip off the top and bottom of the civ icon -->
 			<object z="30" size="0 -5 100% 40" ghost="true" type="image" sprite="remove"/>
 			<object z="30" size="0 100%-5 100% 100%+40" ghost="true" type="image" sprite="remove"/>
-			
+
 			<object z="30" size="0 2 100% 45" ghost="true">
 			    <!-- Specific Name -->
 			    <object size="0 0 100% 20" name="specific" ghost="true" type="text" style="SpecificNameCentered"/>
@@ -1032,13 +1036,13 @@
 			    <!-- Generic Name -->
 			    <object size="0 15 100% 36" name="generic" ghost="true" type="text" style="GenericNameCentered"/>
 			</object>
-			
+
 			<!-- Player Name and Civ -->
 			<object size="0 40 100% 100%">
 			    <object size="50%-64 50%-64 50%+64 50%+64" name="playerCivIcon" type="image" ghost="true"/>
 			    <object size="0 0 100% 100%" name="playerColorBackground" type="image" sprite="playerColorBackground" ghost="true"/>
 			    <object size="0 0 100% 100%" type="image" sprite="bottomEdgedPanelShader" ghost="true"/>
-			    
+
 			    <!-- Why is this being automatically ghosted? In the mean time, set ghost to false -->
 			    <object ghost="false" size="0 0 100% 100%-5" name="player" type="text" style="largeCenteredOutlinedText" tooltip_style="sessionToolTip"/>
 			</object>
@@ -1212,7 +1216,7 @@
 			</repeat>
 		    </object>
 		</object>
-    
+
     <object name="unitPackPanel"
 			size="10 12 100% 100%"
 		>
diff --git a/binaries/data/mods/public/simulation/components/GuiInterface.js b/binaries/data/mods/public/simulation/components/GuiInterface.js
index 0b93128870..aad16514a3 100644
--- a/binaries/data/mods/public/simulation/components/GuiInterface.js
+++ b/binaries/data/mods/public/simulation/components/GuiInterface.js
@@ -28,9 +28,9 @@ GuiInterface.prototype.Init = function()
 /*
  * All of the functions defined below are called via Engine.GuiInterfaceCall(name, arg)
  * from GUI scripts, and executed here with arguments (player, arg).
- * 
- * CAUTION: The input to the functions in this module is not network-synchronised, so it 
- * mustn't affect the simulation state (i.e. the data that is serialised and can affect 
+ *
+ * CAUTION: The input to the functions in this module is not network-synchronised, so it
+ * mustn't affect the simulation state (i.e. the data that is serialised and can affect
  * the behaviour of the rest of the simulation) else it'll cause out-of-sync errors.
  */
 
@@ -43,7 +43,7 @@ GuiInterface.prototype.GetSimulationState = function(player)
 	var ret = {
 		"players": []
 	};
-	
+
 	var cmpPlayerMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_PlayerManager);
 	var n = cmpPlayerMan.GetNumPlayers();
 	for (var i = 0; i < n; ++i)
@@ -51,7 +51,7 @@ GuiInterface.prototype.GetSimulationState = function(player)
 		var playerEnt = cmpPlayerMan.GetPlayerByID(i);
 		var cmpPlayerEntityLimits = Engine.QueryInterface(playerEnt, IID_EntityLimits);
 		var cmpPlayer = Engine.QueryInterface(playerEnt, IID_Player);
-		
+
 		// Work out what phase we are in
 		var cmpTechnologyManager = Engine.QueryInterface(playerEnt, IID_TechnologyManager);
 		var phase = "";
@@ -61,7 +61,7 @@ GuiInterface.prototype.GetSimulationState = function(player)
 			phase = "town";
 		else if (cmpTechnologyManager.IsTechnologyResearched("phase_village"))
 			phase = "village";
-		
+
 		// store player ally/neutral/enemy data as arrays
 		var allies = [];
 		var mutualAllies = [];
@@ -110,7 +110,7 @@ GuiInterface.prototype.GetSimulationState = function(player)
 	{
 		ret.circularMap = cmpRangeManager.GetLosCircular();
 	}
-	
+
 	// Add timeElapsed
 	var cmpTimer = Engine.QueryInterface(SYSTEM_ENTITY, IID_Timer);
 	ret.timeElapsed = cmpTimer.GetTime();
@@ -169,7 +169,7 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 			"selectionGroupName": cmpIdentity.GetSelectionGroupName()
 		};
 	}
-	
+
 	var cmpPosition = Engine.QueryInterface(ent, IID_Position);
 	if (cmpPosition && cmpPosition.IsInWorld())
 	{
@@ -216,7 +216,7 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 				// not in world, set a default?
 				ret.attack.elevationAdaptedRange = ret.attack.maxRange;
 			}
-			
+
 		}
 		else
 		{
@@ -291,16 +291,19 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 	}
 
 	var cmpResourceSupply = Engine.QueryInterface(ent, IID_ResourceSupply);
-	if (cmpResourceSupply)
-	{
-		ret.resourceSupply = {
-			"isInfinite": cmpResourceSupply.IsInfinite(),
-			"max": cmpResourceSupply.GetMaxAmount(),
-			"amount": cmpResourceSupply.GetCurrentAmount(),
-			"type": cmpResourceSupply.GetType(),
+	if (cmpResourceSupply)
+	{
+		ret.resourceSupply = {
+			"isInfinite": cmpResourceSupply.IsInfinite(),
+			"max": cmpResourceSupply.GetMaxAmount(),
+			"amount": cmpResourceSupply.GetCurrentAmount(),
+			"type": cmpResourceSupply.GetType(),
 			"killBeforeGather": cmpResourceSupply.GetKillBeforeGather(),
 			"maxGatherers": cmpResourceSupply.GetMaxGatherers(),
-			"gatherers": cmpResourceSupply.GetGatherers()
+			"gatherers": cmpResourceSupply.GetGatherers(),
+            "throughput": cmpResourceSupply.GetGatherers().reduce(function (total, e)
+                total + Engine.QueryInterface(e, IID_ResourceGatherer).GetTargetGatherRate(ent)
+            , 0)
 		};
 	}
 
@@ -334,7 +337,7 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 			"capacity": cmpGarrisonHolder.GetCapacity()
 		};
 	}
-	
+
 	var cmpPromotion = Engine.QueryInterface(ent, IID_Promotion);
 	if (cmpPromotion)
 	{
@@ -361,7 +364,7 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 		ret.gate = {
 			"locked": cmpGate.IsLocked(),
 		};
-	}	
+	}
 
 	if (!cmpFoundation && cmpIdentity && cmpIdentity.HasClass("BarterMarket"))
 	{
@@ -372,7 +375,7 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 	var cmpHeal = Engine.QueryInterface(ent, IID_Heal);
 	if (cmpHeal)
 	{
-		ret.Healer = { 
+		ret.Healer = {
 			"unhealableClasses": cmpHeal.GetUnhealableClasses(),
 			"healableClasses": cmpHeal.GetHealableClasses(),
 		};
@@ -424,7 +427,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 			"crush": GetTechModifiedProperty(techMods, template, "Armour/Crush", +template.Armour.Crush),
 		};
 	}
-	
+
 	if (template.Attack)
 	{
 		ret.attack = {};
@@ -440,7 +443,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 			};
 		}
 	}
-	
+
 	if (template.BuildRestrictions)
 	{
 		// required properties
@@ -449,7 +452,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 			"territory": template.BuildRestrictions.Territory,
 			"category": template.BuildRestrictions.Category,
 		};
-		
+
 		// optional properties
 		if (template.BuildRestrictions.Distance)
 		{
@@ -479,11 +482,11 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 		if (template.Cost.PopulationBonus) ret.cost.populationBonus = GetTechModifiedProperty(techMods, template, "Cost/PopulationBonus", +template.Cost.PopulationBonus);
 		if (template.Cost.BuildTime) ret.cost.time = GetTechModifiedProperty(techMods, template, "Cost/BuildTime", +template.Cost.BuildTime);
 	}
-	
+
 	if (template.Footprint)
 	{
 		ret.footprint = {"height": template.Footprint.Height};
-		
+
 		if (template.Footprint.Square)
 			ret.footprint.square = {"width": +template.Footprint.Square["@width"], "depth": +template.Footprint.Square["@depth"]};
 		else if (template.Footprint.Circle)
@@ -491,7 +494,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 		else
 			warn("[GetTemplateData] Unrecognized Footprint type");
 	}
-	
+
 	if (template.Obstruction)
 	{
 		ret.obstruction = {
@@ -504,7 +507,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 			"disableBlockPathfinding": ("" + template.Obstruction.DisableBlockPathfinding == "true"),
 			"shape": {}
 		};
-		
+
 		if (template.Obstruction.Static)
 		{
 			ret.obstruction.shape.type = "static";
@@ -573,7 +576,7 @@ GuiInterface.prototype.GetTemplateData = function(player, extendedName)
 			"minTowerOverlap": +template.WallSet.MinTowerOverlap,
 		};
 	}
-	
+
 	if (template.WallPiece)
 	{
 		ret.wallPiece = {"length": +template.WallPiece.Length};
@@ -586,16 +589,16 @@ GuiInterface.prototype.GetTechnologyData = function(player, name)
 {
 	var cmpTechTempMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_TechnologyTemplateManager);
 	var template = cmpTechTempMan.GetTemplate(name);
-	
+
 	if (!template)
 	{
 		warn("Tried to get data for invalid technology: " + name);
 		return null;
 	}
-	
+
 	var ret = {};
-	
-	// Get specific name for this civ or else the generic specific name 
+
+	// Get specific name for this civ or else the generic specific name
 	var cmpPlayer = QueryPlayerIDInterface(player, IID_Player);
 	var specific = undefined;
 	if (template.specificName)
@@ -605,7 +608,7 @@ GuiInterface.prototype.GetTechnologyData = function(player, name)
 		else
 			specific = template.specificName['generic'];
 	}
-	
+
 	ret.name = {
 		"specific": specific,
 		"generic": template.genericName,
@@ -619,24 +622,24 @@ GuiInterface.prototype.GetTechnologyData = function(player, name)
 		"time": template.researchTime ? (+template.researchTime) : 0,
 	}
 	ret.tooltip = template.tooltip;
-	
+
 	if (template.requirementsTooltip)
 		ret.requirementsTooltip = template.requirementsTooltip;
 	else
 		ret.requirementsTooltip = "";
-	
+
 	ret.description = template.description;
-	
+
 	return ret;
 };
 
 GuiInterface.prototype.IsTechnologyResearched = function(player, tech)
 {
 	var cmpTechnologyManager = QueryPlayerIDInterface(player, IID_TechnologyManager);
-	
+
 	if (!cmpTechnologyManager)
 		return false;
-	
+
 	return cmpTechnologyManager.IsTechnologyResearched(tech);
 };
 
@@ -644,10 +647,10 @@ GuiInterface.prototype.IsTechnologyResearched = function(player, tech)
 GuiInterface.prototype.CheckTechnologyRequirements = function(player, tech)
 {
 	var cmpTechnologyManager = QueryPlayerIDInterface(player, IID_TechnologyManager);
-	
+
 	if (!cmpTechnologyManager)
 		return false;
-	
+
 	return cmpTechnologyManager.CanResearch(tech);
 };
 
@@ -751,7 +754,7 @@ GuiInterface.prototype.SetSelectionHighlight = function(player, cmd, selected)
 {
 	var cmpPlayerMan = Engine.QueryInterface(SYSTEM_ENTITY, IID_PlayerManager);
 	var playerColours = {}; // cache of owner -> colour map
-	
+
 	for each (var ent in cmd.entities)
 	{
 		var cmpSelectable = Engine.QueryInterface(ent, IID_Selectable);
@@ -796,11 +799,11 @@ GuiInterface.prototype.GetPlayerEntities = function(player)
 
 /**
  * Displays the rally points of a given list of entities (carried in cmd.entities).
- * 
- * The 'cmd' object may carry its own x/z coordinate pair indicating the location where the rally point should 
- * be rendered, in order to support instantaneously rendering a rally point marker at a specified location 
+ *
+ * The 'cmd' object may carry its own x/z coordinate pair indicating the location where the rally point should
+ * be rendered, in order to support instantaneously rendering a rally point marker at a specified location
  * instead of incurring a delay while PostNetworkCommand processes the set-rallypoint command (see input.js).
- * If cmd doesn't carry a custom location, then the position to render the marker at will be read from the 
+ * If cmd doesn't carry a custom location, then the position to render the marker at will be read from the
  * RallyPoint component.
  */
 GuiInterface.prototype.DisplayRallyPoint = function(player, cmd)
@@ -815,16 +818,16 @@ GuiInterface.prototype.DisplayRallyPoint = function(player, cmd)
 		if (cmpRallyPointRenderer)
 			cmpRallyPointRenderer.SetDisplayed(false);
 	}
-	
+
 	this.entsRallyPointsDisplayed = [];
-	
+
 	// Show the rally points for the passed entities
 	for each (var ent in cmd.entities)
 	{
 		var cmpRallyPointRenderer = Engine.QueryInterface(ent, IID_RallyPointRenderer);
 		if (!cmpRallyPointRenderer)
 			continue;
-		
+
 		// entity must have a rally point component to display a rally point marker
 		// (regardless of whether cmd specifies a custom location)
 		var cmpRallyPoint = Engine.QueryInterface(ent, IID_RallyPoint);
@@ -841,7 +844,7 @@ GuiInterface.prototype.DisplayRallyPoint = function(player, cmd)
 		// override the real rally point position; otherwise use the real position
 		var pos;
 		if (cmd.x && cmd.z)
-			pos = cmd; 
+			pos = cmd;
 		else
 			pos = cmpRallyPoint.GetPositions()[0]; // may return undefined if no rally point is set
 
@@ -853,7 +856,7 @@ GuiInterface.prototype.DisplayRallyPoint = function(player, cmd)
 			else if (cmd.queued == false)
 				cmpRallyPointRenderer.SetPosition({'x': pos.x, 'y': pos.z}); // SetPosition takes a CFixedVector2D which has X/Y components, not X/Z
 			cmpRallyPointRenderer.SetDisplayed(true);
-			
+
 			// remember which entities have their rally points displayed so we can hide them again
 			this.entsRallyPointsDisplayed.push(ent);
 		}
@@ -864,7 +867,7 @@ GuiInterface.prototype.DisplayRallyPoint = function(player, cmd)
  * Display the building placement preview.
  * cmd.template is the name of the entity template, or "" to disable the preview.
  * cmd.x, cmd.z, cmd.angle give the location.
- * 
+ *
  * Returns result object from CheckPlacement:
  * 	{
  *		"success":	true iff the placement is valid, else false
@@ -936,34 +939,34 @@ GuiInterface.prototype.SetBuildingPlacementPreview = function(player, cmd)
 };
 
 /**
- * Previews the placement of a wall between cmd.start and cmd.end, or just the starting piece of a wall if cmd.end is not 
+ * Previews the placement of a wall between cmd.start and cmd.end, or just the starting piece of a wall if cmd.end is not
  * specified. Returns an object with information about the list of entities that need to be newly constructed to complete
  * at least a part of the wall, or false if there are entities required to build at least part of the wall but none of
  * them can be validly constructed.
- * 
+ *
  * It's important to distinguish between three lists of entities that are at play here, because they may be subsets of one
  * another depending on things like snapping and whether some of the entities inside them can be validly positioned.
  * We have:
  *    - The list of entities that previews the wall. This list is usually equal to the entities required to construct the
  *      entire wall. However, if there is snapping to an incomplete tower (i.e. a foundation), it includes extra entities
  *      to preview the completed tower on top of its foundation.
- *      
+ *
  *    - The list of entities that need to be newly constructed to build the entire wall. This list is regardless of whether
  *      any of them can be validly positioned. The emphasishere here is on 'newly'; this list does not include any existing
  *      towers at either side of the wall that we snapped to. Or, more generally; it does not include any _entities_ that we
  *      snapped to; we might still snap to e.g. terrain, in which case the towers on either end will still need to be newly
  *      constructed.
- *      
+ *
  *    - The list of entities that need to be newly constructed to build at least a part of the wall. This list is the same
  *      as the one above, except that it is truncated at the first entity that cannot be validly positioned. This happens
  *      e.g. if the player tries to build a wall straight through an obstruction. Note that any entities that can be validly
  *      constructed but come after said first invalid entity are also truncated away.
- * 
+ *
  * With this in mind, this method will return false if the second list is not empty, but the third one is. That is, if there
  * were entities that are needed to build the wall, but none of them can be validly constructed. False is also returned in
  * case of unexpected errors (typically missing components), and when clearing the preview by passing an empty wallset
  * argument (see below). Otherwise, it will return an object with the following information:
- * 
+ *
  * result: {
  *   'startSnappedEnt':   ID of the entity that we snapped to at the starting side of the wall. Currently only supports towers.
  *   'endSnappedEnt':     ID of the entity that we snapped to at the (possibly truncated) ending side of the wall. Note that this
@@ -972,7 +975,7 @@ GuiInterface.prototype.SetBuildingPlacementPreview = function(player, cmd)
  *                        supports towers.
  *   'pieces':            Array with the following data for each of the entities in the third list:
  *    [{
- *       'template':      Template name of the entity. 
+ *       'template':      Template name of the entity.
  *       'x':             X coordinate of the entity's position.
  *       'z':             Z coordinate of the entity's position.
  *       'angle':         Rotation around the Y axis of the entity (in radians).
@@ -987,7 +990,7 @@ GuiInterface.prototype.SetBuildingPlacementPreview = function(player, cmd)
  *     'populationBonus': ...,
  *   }
  * }
- * 
+ *
  * @param cmd.wallSet Object holding the set of wall piece template names. Set to an empty value to clear the preview.
  * @param cmd.start Starting point of the wall segment being created.
  * @param cmd.end (Optional) Ending point of the wall segment being created. If not defined, it is understood that only
@@ -999,27 +1002,27 @@ GuiInterface.prototype.SetBuildingPlacementPreview = function(player, cmd)
 GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 {
 	var wallSet = cmd.wallSet;
-	
+
 	var start = {
 		"pos": cmd.start,
 		"angle": 0,
 		"snapped": false,                       // did the start position snap to anything?
 		"snappedEnt": INVALID_ENTITY,           // if we snapped, was it to an entity? if yes, holds that entity's ID
 	};
-	
+
 	var end = {
 		"pos": cmd.end,
 		"angle": 0,
 		"snapped": false,                       // did the start position snap to anything?
 		"snappedEnt": INVALID_ENTITY,           // if we snapped, was it to an entity? if yes, holds that entity's ID
 	};
-	
+
 	// --------------------------------------------------------------------------------
 	// do some entity cache management and check for snapping
-	
+
 	if (!this.placementWallEntities)
 		this.placementWallEntities = {};
-	
+
 	if (!wallSet)
 	{
 		// we're clearing the preview, clear the entity cache and bail
@@ -1028,12 +1031,12 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 		{
 			for each (var ent in this.placementWallEntities[tpl].entities)
 				Engine.DestroyEntity(ent);
-			
+
 			this.placementWallEntities[tpl].numUsed = 0;
 			this.placementWallEntities[tpl].entities = [];
 			// keep template data around
 		}
-		
+
 		return false;
 	}
 	else
@@ -1047,10 +1050,10 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				if (pos)
 					pos.MoveOutOfWorld();
 			}
-			
+
 			this.placementWallEntities[tpl].numUsed = 0;
 		}
-		
+
 		// Create cache entries for templates we haven't seen before
 		for each (var tpl in wallSet.templates)
 		{
@@ -1061,7 +1064,7 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 					"entities": [],
 					"templateData": this.GetTemplateData(player, tpl),
 				};
-				
+
 				// ensure that the loaded template data contains a wallPiece component
 				if (!this.placementWallEntities[tpl].templateData.wallPiece)
 				{
@@ -1071,11 +1074,11 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 			}
 		}
 	}
-	
+
 	// prevent division by zero errors further on if the start and end positions are the same
 	if (end.pos && (start.pos.x === end.pos.x && start.pos.z === end.pos.z))
 		end.pos = undefined;
-	
+
 	// See if we need to snap the start and/or end coordinates to any of our list of snap entities. Note that, despite the list
 	// of snapping candidate entities, it might still snap to e.g. terrain features. Use the "ent" key in the returned snapping
 	// data to determine whether it snapped to an entity (if any), and to which one (see GetFoundationSnapData).
@@ -1089,18 +1092,18 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 			"snapEntities": cmd.snapEntities,
 			"snapRadius": snapRadius,
 		});
-		
+
 		if (startSnapData)
 		{
 			start.pos.x = startSnapData.x;
 			start.pos.z = startSnapData.z;
 			start.angle = startSnapData.angle;
 			start.snapped = true;
-			
+
 			if (startSnapData.ent)
-				start.snappedEnt = startSnapData.ent; 
+				start.snappedEnt = startSnapData.ent;
 		}
-		
+
 		if (end.pos)
 		{
 			var endSnapData = this.GetFoundationSnapData(player, {
@@ -1110,41 +1113,41 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				"snapEntities": cmd.snapEntities,
 				"snapRadius": snapRadius,
 			});
-			
+
 			if (endSnapData)
 			{
 				end.pos.x = endSnapData.x;
 				end.pos.z = endSnapData.z;
 				end.angle = endSnapData.angle;
 				end.snapped = true;
-				
+
 				if (endSnapData.ent)
 					end.snappedEnt = endSnapData.ent;
 			}
 		}
 	}
-	
+
 	// clear the single-building preview entity (we'll be rolling our own)
 	this.SetBuildingPlacementPreview(player, {"template": ""});
-	
+
 	// --------------------------------------------------------------------------------
 	// calculate wall placement and position preview entities
-	
+
 	var result = {
 		"pieces": [],
 		"cost": {"food": 0, "wood": 0, "stone": 0, "metal": 0, "population": 0, "populationBonus": 0, "time": 0},
 	};
-	
+
 	var previewEntities = [];
 	if (end.pos)
 		previewEntities = GetWallPlacement(this.placementWallEntities, wallSet, start, end); // see helpers/Walls.js
-	
-	// For wall placement, we may (and usually do) need to have wall pieces overlap each other more than would 
+
+	// For wall placement, we may (and usually do) need to have wall pieces overlap each other more than would
 	// otherwise be allowed by their obstruction shapes. However, during this preview phase, this is not so much of
-	// an issue, because all preview entities have their obstruction components deactivated, meaning that their 
+	// an issue, because all preview entities have their obstruction components deactivated, meaning that their
 	// obstruction shapes do not register in the simulation and hence cannot affect it. This implies that the preview
 	// entities cannot be found to obstruct each other, which largely solves the issue of overlap between wall pieces.
-	
+
 	// Note that they will still be obstructed by existing shapes in the simulation (that have the BLOCK_FOUNDATION
 	// flag set), which is what we want. The only exception to this is when snapping to existing towers (or
 	// foundations thereof); the wall segments that connect up to these will be found to be obstructed by the
@@ -1152,17 +1155,17 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 	// we manually set the control group of the outermost wall pieces equal to those of the snapped-to towers, so
 	// that they are free from mutual obstruction (per definition of obstruction control groups). This is done by
 	// assigning them an extra "controlGroup" field, which we'll then set during the placement loop below.
-	
+
 	// Additionally, in the situation that we're snapping to merely a foundation of a tower instead of a fully
 	// constructed one, we'll need an extra preview entity for the starting tower, which also must not be obstructed
 	// by the foundation it snaps to.
-	
+
 	if (start.snappedEnt && start.snappedEnt != INVALID_ENTITY)
 	{
 		var startEntObstruction = Engine.QueryInterface(start.snappedEnt, IID_Obstruction);
 		if (previewEntities.length > 0 && startEntObstruction)
 			previewEntities[0].controlGroups = [startEntObstruction.GetControlGroup()];
-		
+
 		// if we're snapping to merely a foundation, add an extra preview tower and also set it to the same control group
 		var startEntState = this.GetEntityState(player, start.snappedEnt);
 		if (startEntState.foundation)
@@ -1182,19 +1185,19 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 	}
 	else
 	{
-		// Didn't snap to an existing entity, add the starting tower manually. To prevent odd-looking rotation jumps 
-		// when shift-clicking to build a wall, reuse the placement angle that was last seen on a validly positioned 
+		// Didn't snap to an existing entity, add the starting tower manually. To prevent odd-looking rotation jumps
+		// when shift-clicking to build a wall, reuse the placement angle that was last seen on a validly positioned
 		// wall piece.
-		
+
 		// To illustrate the last point, consider what happens if we used some constant instead, say, 0. Issuing the
 		// build command for a wall is asynchronous, so when the preview updates after shift-clicking, the wall piece
 		// foundations are not registered yet in the simulation. This means they cannot possibly be picked in the list
 		// of candidate entities for snapping. In the next preview update, we therefore hit this case, and would rotate
-		// the preview to 0 radians. Then, after one or two simulation updates or so, the foundations register and 
+		// the preview to 0 radians. Then, after one or two simulation updates or so, the foundations register and
 		// onSimulationUpdate in session.js updates the preview again. It first grabs a new list of snapping candidates,
 		// which this time does include the new foundations; so we snap to the entity, and rotate the preview back to
 		// the foundation's angle.
-		
+
 		// The result is a noticeable rotation to 0 and back, which is undesirable. So, for a split second there until
 		// the simulation updates, we fake it by reusing the last angle and hope the player doesn't notice.
 		previewEntities.unshift({
@@ -1203,14 +1206,14 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 			"angle": (previewEntities.length > 0 ? previewEntities[0].angle : this.placementWallLastAngle)
 		});
 	}
-	
+
 	if (end.pos)
 	{
 		// Analogous to the starting side case above
 		if (end.snappedEnt && end.snappedEnt != INVALID_ENTITY)
 		{
 			var endEntObstruction = Engine.QueryInterface(end.snappedEnt, IID_Obstruction);
-			
+
 			// Note that it's possible for the last entity in previewEntities to be the same as the first, i.e. the
 			// same wall piece snapping to both a starting and an ending tower. And it might be more common than you would
 			// expect; the allowed overlap between wall segments and towers facilitates this to some degree. To deal with
@@ -1221,7 +1224,7 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				previewEntities[previewEntities.length-1].controlGroups = (previewEntities[previewEntities.length-1].controlGroups || []);
 				previewEntities[previewEntities.length-1].controlGroups.push(endEntObstruction.GetControlGroup());
 			}
-			
+
 			// if we're snapping to a foundation, add an extra preview tower and also set it to the same control group
 			var endEntState = this.GetEntityState(player, end.snappedEnt);
 			if (endEntState.foundation)
@@ -1248,37 +1251,37 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 			});
 		}
 	}
-	
+
 	var cmpTerrain = Engine.QueryInterface(SYSTEM_ENTITY, IID_Terrain);
 	if (!cmpTerrain)
 	{
 		error("[SetWallPlacementPreview] System Terrain component not found");
 		return false;
 	}
-	
+
 	var cmpRangeManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
 	if (!cmpRangeManager)
 	{
 		error("[SetWallPlacementPreview] System RangeManager component not found");
 		return false;
 	}
-	
+
 	// Loop through the preview entities, and construct the subset of them that need to be, and can be, validly constructed
 	// to build at least a part of the wall (meaning that the subset is truncated after the first entity that needs to be,
 	// but cannot validly be, constructed). See method-level documentation for more details.
-	
+
 	var allPiecesValid = true;
 	var numRequiredPieces = 0; // number of entities that are required to build the entire wall, regardless of validity
-	
+
 	for (var i = 0; i < previewEntities.length; ++i)
 	{
 		var entInfo = previewEntities[i];
-		
+
 		var ent = null;
 		var tpl = entInfo.template;
 		var tplData = this.placementWallEntities[tpl].templateData;
 		var entPool = this.placementWallEntities[tpl];
-		
+
 		if (entPool.numUsed >= entPool.entities.length)
 		{
 			// allocate new entity
@@ -1290,13 +1293,13 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 			 // reuse an existing one
 			ent = entPool.entities[entPool.numUsed];
 		}
-		
+
 		if (!ent)
 		{
 			error("[SetWallPlacementPreview] Failed to allocate or reuse preview entity of template '" + tpl + "'");
 			continue;
 		}
-		
+
 		// move piece to right location
 		// TODO: consider reusing SetBuildingPlacementReview for this, enhanced to be able to deal with multiple entities
 		var cmpPosition = Engine.QueryInterface(ent, IID_Position);
@@ -1304,18 +1307,18 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 		{
 			cmpPosition.JumpTo(entInfo.pos.x, entInfo.pos.z);
 			cmpPosition.SetYRotation(entInfo.angle);
-			
+
 			// if this piece is a tower, then it should have a Y position that is at least as high as its surrounding pieces
 			if (tpl === wallSet.templates.tower)
 			{
 				var terrainGroundPrev = null;
 				var terrainGroundNext = null;
-				
+
 				if (i > 0)
 					terrainGroundPrev = cmpTerrain.GetGroundLevel(previewEntities[i-1].pos.x, previewEntities[i-1].pos.z);
 				if (i < previewEntities.length - 1)
 					terrainGroundNext = cmpTerrain.GetGroundLevel(previewEntities[i+1].pos.x, previewEntities[i+1].pos.z);
-				
+
 				if (terrainGroundPrev != null || terrainGroundNext != null)
 				{
 					var targetY = Math.max(terrainGroundPrev, terrainGroundNext);
@@ -1323,27 +1326,27 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				}
 			}
 		}
-		
+
 		var cmpObstruction = Engine.QueryInterface(ent, IID_Obstruction);
 		if (!cmpObstruction)
 		{
 			error("[SetWallPlacementPreview] Preview entity of template '" + tpl + "' does not have an Obstruction component");
 			continue;
 		}
-		
+
 		// Assign any predefined control groups. Note that there can only be 0, 1 or 2 predefined control groups; if there are
 		// more, we've made a programming error. The control groups are assigned from the entInfo.controlGroups array on a
 		// first-come first-served basis; the first value in the array is always assigned as the primary control group, and
 		// any second value as the secondary control group.
-		
+
 		// By default, we reset the control groups to their standard values. Remember that we're reusing entities; if we don't
 		// reset them, then an ending wall segment that was e.g. at one point snapped to an existing tower, and is subsequently
 		// reused as a non-snapped ending wall segment, would no longer be capable of being obstructed by the same tower it was
 		// once snapped to.
-		
+
 		var primaryControlGroup = ent;
 		var secondaryControlGroup = INVALID_ENTITY;
-		
+
 		if (entInfo.controlGroups && entInfo.controlGroups.length > 0)
 		{
 			if (entInfo.controlGroups.length > 2)
@@ -1351,21 +1354,21 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				error("[SetWallPlacementPreview] Encountered preview entity of template '" + tpl + "' with more than 2 initial control groups");
 				break;
 			}
-			
+
 			primaryControlGroup = entInfo.controlGroups[0];
 			if (entInfo.controlGroups.length > 1)
 				secondaryControlGroup = entInfo.controlGroups[1];
 		}
-		
+
 		cmpObstruction.SetControlGroup(primaryControlGroup);
 		cmpObstruction.SetControlGroup2(secondaryControlGroup);
-		
+
 		// check whether this wall piece can be validly positioned here
 		var validPlacement = false;
-		
+
 		var cmpOwnership = Engine.QueryInterface(ent, IID_Ownership);
 		cmpOwnership.SetOwner(player);
-		
+
 		// Check whether it's in a visible or fogged region
 		//  tell GetLosVisibility to force RetainInFog because preview entities set this to false,
 		//	which would show them as hidden instead of fogged
@@ -1379,7 +1382,7 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				error("[SetWallPlacementPreview] cmpBuildRestrictions not defined for preview entity of template '" + tpl + "'");
 				continue;
 			}
-			
+
 			// TODO: Handle results of CheckPlacement
 			validPlacement = (cmpBuildRestrictions && cmpBuildRestrictions.CheckPlacement().success);
 
@@ -1391,18 +1394,18 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 		}
 
 		allPiecesValid = allPiecesValid && validPlacement;
-		
+
 		// The requirement below that all pieces so far have to have valid positions, rather than only this single one,
 		// ensures that no more foundations will be placed after a first invalidly-positioned piece. (It is possible
-		// for pieces past some invalidly-positioned ones to still have valid positions, e.g. if you drag a wall 
+		// for pieces past some invalidly-positioned ones to still have valid positions, e.g. if you drag a wall
 		// through and past an existing building).
-		
+
 		// Additionally, the excludeFromResult flag is set for preview entities that were manually added to be placed
 		// on top of foundations of incompleted towers that we snapped to; they must not be part of the result.
-		
+
 		if (!entInfo.excludeFromResult)
 			numRequiredPieces++;
-		
+
 		if (allPiecesValid && !entInfo.excludeFromResult)
 		{
 			result.pieces.push({
@@ -1412,7 +1415,7 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 				"angle": entInfo.angle,
 			});
 			this.placementWallLastAngle = entInfo.angle;
-			
+
 			// grab the cost of this wall piece and add it up (note; preview entities don't have their Cost components
 			// copied over, so we need to fetch it from the template instead).
 			// TODO: we should really use a Cost object or at least some utility functions for this, this is mindless
@@ -1442,27 +1445,27 @@ GuiInterface.prototype.SetWallPlacementPreview = function(player, cmd)
 
 		entPool.numUsed++;
 	}
-	
+
 	// If any were entities required to build the wall, but none of them could be validly positioned, return failure
 	// (see method-level documentation).
 	if (numRequiredPieces > 0 && result.pieces.length == 0)
 		return false;
-	
+
 	if (start.snappedEnt && start.snappedEnt != INVALID_ENTITY)
 		result.startSnappedEnt = start.snappedEnt;
-	
+
 	// We should only return that we snapped to an entity if all pieces up until that entity can be validly constructed,
 	// i.e. are included in result.pieces (see docs for the result object).
 	if (end.pos && end.snappedEnt && end.snappedEnt != INVALID_ENTITY && allPiecesValid)
 		result.endSnappedEnt = end.snappedEnt;
-	
+
 	return result;
 };
 
 /**
  * Given the current position {data.x, data.z} of an foundation of template data.template, returns the position and angle to snap
  * it to (if necessary/useful).
- * 
+ *
  * @param data.x            The X position of the foundation to snap.
  * @param data.z            The Z position of the foundation to snap.
  * @param data.template     The template to get the foundation snapping data for.
@@ -1484,38 +1487,38 @@ GuiInterface.prototype.GetFoundationSnapData = function(player, data)
 		warn("[GetFoundationSnapData] Failed to load template '" + data.template + "'");
 		return false;
 	}
-	
+
 	if (data.snapEntities && data.snapRadius && data.snapRadius > 0)
 	{
 		// see if {data.x, data.z} is inside the snap radius of any of the snap entities; and if so, to which it is closest
 		// (TODO: break unlikely ties by choosing the lowest entity ID)
-		
+
 		var minDist2 = -1;
 		var minDistEntitySnapData = null;
 		var radius2 = data.snapRadius * data.snapRadius;
-		
+
 		for each (var ent in data.snapEntities)
 		{
 			var cmpPosition = Engine.QueryInterface(ent, IID_Position);
 			if (!cmpPosition || !cmpPosition.IsInWorld())
 				continue;
-			
+
 			var pos = cmpPosition.GetPosition();
 			var dist2 = (data.x - pos.x) * (data.x - pos.x) + (data.z - pos.z) * (data.z - pos.z);
 			if (dist2 > radius2)
 				continue;
-			
+
 			if (minDist2 < 0 || dist2 < minDist2)
 			{
 				minDist2 = dist2;
 				minDistEntitySnapData = {"x": pos.x, "z": pos.z, "angle": cmpPosition.GetRotation().y, "ent": ent};
 			}
 		}
-		
+
 		if (minDistEntitySnapData != null)
 			return minDistEntitySnapData;
 	}
-	
+
 	if (template.BuildRestrictions.Category == "Dock")
 	{
 		// warning: copied almost identically in helpers/command.js , "GetDockAngle".
@@ -1525,7 +1528,7 @@ GuiInterface.prototype.GetFoundationSnapData = function(player, data)
 		{
 			return false;
 		}
-		
+
 		// Get footprint size
 		var halfSize = 0;
 		if (template.Footprint.Square)
@@ -1536,7 +1539,7 @@ GuiInterface.prototype.GetFoundationSnapData = function(player, data)
 		{
 			halfSize = template.Footprint.Circle["@radius"];
 		}
-		
+
 		/* Find direction of most open water, algorithm:
 		 *	1. Pick points in a circle around dock
 		 *	2. If point is in water, add to array
@@ -1556,7 +1559,7 @@ GuiInterface.prototype.GetFoundationSnapData = function(player, data)
 				var d = halfSize*(dist+1);
 				var nx = data.x - d*Math.sin(angle);
 				var nz = data.z + d*Math.cos(angle);
-				
+
 				if (cmpTerrain.GetGroundLevel(nx, nz) < cmpWaterManager.GetWaterLevel(nx, nz))
 				{
 					waterPoints.push(i);
@@ -1590,7 +1593,7 @@ GuiInterface.prototype.GetFoundationSnapData = function(player, data)
 					count = consec[c];
 				}
 			}
-			
+
 			// If we've found a shoreline, stop searching
 			if (count != numPoints-1)
 			{
@@ -1615,7 +1618,7 @@ function isIdleUnit(ent, idleClass)
 {
 	var cmpUnitAI = Engine.QueryInterface(ent, IID_UnitAI);
 	var cmpIdentity = Engine.QueryInterface(ent, IID_Identity);
-	
+
 	// TODO: Do something with garrisoned idle units
 	return (cmpUnitAI && cmpIdentity && cmpUnitAI.IsIdle() && !cmpUnitAI.IsGarrisoned() && idleClass && cmpIdentity.HasClass(idleClass));
 }
@@ -1767,7 +1770,7 @@ GuiInterface.prototype.OnGlobalEntityRenamed = function(msg)
 // trusted and indicates the player associated with the current client; no data should
 // be returned unless this player is meant to be able to see it.)
 var exposedFunctions = {
-	
+
 	"GetSimulationState": 1,
 	"GetExtendedSimulationState": 1,
 	"GetRenamedEntities": 1,
diff --git a/binaries/data/mods/public/simulation/components/ResourceSupply.js b/binaries/data/mods/public/simulation/components/ResourceSupply.js
index 84fff10736..e3677ab6c5 100644
--- a/binaries/data/mods/public/simulation/components/ResourceSupply.js
+++ b/binaries/data/mods/public/simulation/components/ResourceSupply.js
@@ -7,13 +7,13 @@ ResourceSupply.prototype.Schema =
 		"<Type>food.meat</Type>" +
 	"</a:example>" +
 	"<element name='KillBeforeGather' a:help='Whether this entity must be killed (health reduced to 0) before its resources can be gathered'>" +
-		"<data type='boolean'/>" +
-	"</element>" +
-	"<element name='Amount' a:help='Amount of resources available from this entity'>" +
-		"<choice><data type='nonNegativeInteger'/><value>Infinity</value></choice>" +
-	"</element>" +
-	"<element name='Type' a:help='Type of resources'>" +
-		"<choice>" +
+		"<data type='boolean'/>" +
+	"</element>" +
+	"<element name='Amount' a:help='Amount of resources available from this entity'>" +
+		"<choice><data type='nonNegativeInteger'/><value>Infinity</value></choice>" +
+	"</element>" +
+	"<element name='Type' a:help='Type of resources'>" +
+		"<choice>" +
 			"<value>wood.tree</value>" +
 			"<value>wood.ruins</value>" +
 			"<value>stone.rock</value>" +
@@ -29,32 +29,63 @@ ResourceSupply.prototype.Schema =
 			"<value>treasure.metal</value>" +
 			"<value>treasure.food</value>" +
 		"</choice>" +
-	"</element>" +
-	"<element name='MaxGatherers' a:help='Amount of gatherers who can gather resources from this entity at the same time'>" +
-		"<data type='nonNegativeInteger'/>" +
-	"</element>" +
-	"<optional>" +
-		"<element name='DiminishingReturns' a:help='The rate at which adding more gatherers decreases overall efficiency. Lower numbers = faster dropoff. Leave the element out for no diminishing returns.'>" +
-			"<ref name='positiveDecimal'/>" +
-		"</element>" +
-	"</optional>";
-
-ResourceSupply.prototype.Init = function()
-{
-	// Current resource amount (non-negative)
-	this.amount = this.GetMaxAmount();
-    this.gatherers = [];	// list of IDs
-    this.infinite = !isFinite(+this.template.Amount);
-};
-
-ResourceSupply.prototype.IsInfinite = function()
-{
-	return this.infinite;
-};
-
-ResourceSupply.prototype.GetKillBeforeGather = function()
-{
-	return (this.template.KillBeforeGather == "true");
+	"</element>" +
+	"<optional>" +
+		"<element name='Regeneration' a:help='Controls whether this resource can regenerate its remaining amount.'>" +
+			"<interleave>" +
+				"<element name='Rate' a:help='Optional regeneration rate. Resources/second if the growth is linear or the rate of quadratic growth if the growth is quadratic.'>" +
+					"<ref name='nonNegativeDecimal'/>" +
+				"</element>" +
+				"<optional>" +
+					"<element name='Acceleration' a:help='Controls the curve the regeneration rate will follow for quadratic growth; does nothing for linear growth.'>" +
+						"<ref name='nonNegativeDecimal'/>" +
+					"</element>" +
+				"</optional>" +
+				"<element name='Delay' a:help='Seconds between when the number of gatherers hit 0 and the resource starts regenerating.'>" +
+					"<data type='nonNegativeInteger'/>" +
+				"</element>" +
+				"<element name='Growth' a:help='Growth formula for regeneration. Either linear or quadratic. Linear continues at a steady rate, while quadratic gets faster over time.'>" +
+					"<choice>" +
+						"<value>linear</value>" +
+						"<value>quadratic</value>" +
+					"</choice>" +
+				"</element>" +
+			"</interleave>" +
+		"</element>" +
+	"</optional>" +
+	"<element name='MaxGatherers' a:help='Amount of gatherers who can gather resources from this entity at the same time'>" +
+		"<data type='nonNegativeInteger'/>" +
+	"</element>" +
+	"<optional>" +
+		"<element name='DiminishingReturns' a:help='The rate at which adding more gatherers decreases overall efficiency. Lower numbers = faster dropoff. Leave the element out for no diminishing returns.'>" +
+			"<ref name='positiveDecimal'/>" +
+		"</element>" +
+	"</optional>";
+
+ResourceSupply.prototype.Init = function()
+{
+	// Current resource amount (non-negative)
+	this.amount = this.GetMaxAmount();
+    this.gatherers = [];	// list of IDs
+    this.infinite = !isFinite(+this.template.Amount);
+	if (this.template.Regeneration) {
+		this.regenRate = +this.template.Regeneration.Rate;
+		if (this.template.Regeneration.Acceleration)
+			this.regenAccel = +this.template.Regeneration.Acceleration;
+		this.regenDelay = +this.template.Regeneration.Delay;
+	}
+	if (this.IsRegenerative())
+		this.RegenerateResources();
+};
+
+ResourceSupply.prototype.IsInfinite = function()
+{
+	return this.infinite;
+};
+
+ResourceSupply.prototype.GetKillBeforeGather = function()
+{
+	return (this.template.KillBeforeGather == "true");
 };
 
 ResourceSupply.prototype.GetMaxAmount = function()
@@ -74,34 +105,71 @@ ResourceSupply.prototype.GetMaxGatherers = function()
 
 ResourceSupply.prototype.GetGatherers = function()
 {
-	return this.gatherers;
-};
-
-ResourceSupply.prototype.GetDiminishingReturns = function()
-{
-	if ("DiminishingReturns" in this.template)
-		return ApplyTechModificationsToEntity("ResourceSupply/DiminishingReturns", +this.template.DiminishingReturns, this.entity);
-	return null;
-};
-
-ResourceSupply.prototype.TakeResources = function(rate)
-{
-	if (this.infinite)
-		return { "amount": rate, "exhausted": false };
-
-	// 'rate' should be a non-negative integer
-
-	var old = this.amount;
+	return this.gatherers;
+};
+
+ResourceSupply.prototype.GetDiminishingReturns = function()
+{
+	if ("DiminishingReturns" in this.template)
+		return ApplyTechModificationsToEntity("ResourceSupply/DiminishingReturns", +this.template.DiminishingReturns, this.entity);
+	return null;
+};
+
+ResourceSupply.prototype.TakeResources = function(rate)
+{
+	if (this.infinite)
+		return { "amount": rate, "exhausted": false };
+
+	// 'rate' should be a non-negative integer
+
+	var old = this.amount;
 	this.amount = Math.max(0, old - rate);
 	var change = old - this.amount;
 
 	// Remove entities that have been exhausted
-	if (this.amount == 0)
+	if (this.amount == 0 && !this.IsRegenerative())
 		Engine.DestroyEntity(this.entity);
 
 	Engine.PostMessage(this.entity, MT_ResourceSupplyChanged, { "from": old, "to": this.amount });
 
-	return { "amount": change, "exhausted": (this.amount == 0) };
+	return { "amount": change, "exhausted": this.amount == 0 };
+};
+
+ResourceSupply.prototype.RegenerateResources = function(data, lateness)
+{
+	var max = this.GetMaxAmount();
+	if (this.gatherers.length == 0 && !this.regenDelayTimer && this.amount < max)
+	{
+		var old = this.amount;
+		if (this.regenGrowth == "linear")
+			this.amount = Math.min(max, this.amount + data.rate);
+		else
+			this.amount = Math.min(max, this.amount + Math.max(1, data.rate * max * (data.acceleration * this.amount / max -Math.pow(this.amount / max, 2)) / 100));
+		Engine.PostMessage(this.entity, MT_ResourceSupplyChanged, { "from": old, "to": this.amount });
+	}
+	var cmpTimer = Engine.QueryInterface(SYSTEM_ENTITY, IID_Timer);
+	var regenRate = this.GetRegenerationRate();
+	var absRegen = Math.abs(regenRate);
+	if (Math.floor(regenRate) == regenRate || this.regenGrowth == "quadratic")
+		cmpTimer.SetTimeout(this.entity, IID_ResourceSupply, "RegenerateResources", 1000, { "rate": regenRate, "acceleration": this.GetRegenerationAcceleration() });
+	else
+		cmpTimer.SetTimeout(this.entity, IID_ResourceSupply, "RegenerateResources", 1000 / absRegen,
+				{ "rate": absRegen == regenRate ? 1 : -1 });
+};
+
+ResourceSupply.prototype.StartRegenerationDelayTimer = function()
+{
+	if (!this.regenDelayTimer) {
+		var cmpTimer = Engine.QueryInterface(SYSTEM_ENTITY, IID_Timer);
+		this.regenDelayTimer = cmpTimer.SetTimeout(this.entity, IID_ResourceSupply, "CancelRegenerationDelayTimer", this.GetRegenerationDelay() * 1000, null);
+	}
+};
+
+ResourceSupply.prototype.CancelRegenerationDelayTimer = function()
+{
+	var cmpTimer = Engine.QueryInterface(SYSTEM_ENTITY, IID_Timer);
+	cmpTimer.CancelTimer(this.regenDelayTimer);
+	this.regenDelayTimer = null;
 };
 
 ResourceSupply.prototype.GetType = function()
@@ -119,18 +187,50 @@ ResourceSupply.prototype.IsAvailable = function(gathererID)
 	return false;
 };
 
+ResourceSupply.prototype.IsRegenerative = function()
+{
+	return this.GetRegenerationRate() != 0;
+};
+
+ResourceSupply.prototype.GetTerritoryOwner = function ()
+{
+	var cmpPlayerManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_PlayerManager);
+	var cmpTerritoryManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_TerritoryManager);
+	var cmpPosition = Engine.QueryInterface(this.entity, IID_Position);
+	if (!(cmpPosition && cmpPosition.IsInWorld()))
+		return 0;  // Something's wrong, just say we're in neutral territory.
+	var pos = cmpPosition.GetPosition2D();
+	return cmpPlayerManager.GetPlayerByID(cmpTerritoryManager.GetOwner(pos.x, pos.y));
+};
+
+ResourceSupply.prototype.GetRegenerationRate = function()
+{
+	return ApplyTechModificationsToPlayer("ResourceSupply/Regeneration/Rate", this.regenRate, this.GetTerritoryOwner());
+};
+
+ResourceSupply.prototype.GetRegenerationAcceleration = function()
+{
+	return ApplyTechModificationsToPlayer("ResourceSupply/Regeneration/Acceleration", this.regenAccel, this.GetTerritoryOwner());
+};
+
+ResourceSupply.prototype.GetRegenerationDelay = function()
+{
+	return ApplyTechModificationsToPlayer("ResourcesSupply/Regeneration/Delay", this.regenDelay, this.GetTerritoryOwner());
+};
+
 ResourceSupply.prototype.AddGatherer = function(gathererID)
 {
 	if (!this.IsAvailable(gathererID))
 		return false;
- 	
+
 	if (this.gatherers.indexOf(gathererID) === -1)
 	{
 		this.gatherers.push(gathererID);
+		this.CancelRegenerationDelayTimer();
 		// broadcast message, mainly useful for the AIs.
 		Engine.PostMessage(this.entity, MT_ResourceSupplyGatherersChanged, { "to": this.gatherers });
 	}
-	
+
 	return true;
 };
 
@@ -143,6 +243,8 @@ ResourceSupply.prototype.RemoveGatherer = function(gathererID)
 		// broadcast message, mainly useful for the AIs.
 		Engine.PostMessage(this.entity, MT_ResourceSupplyGatherersChanged, { "to": this.gatherers });
 	}
+	if (this.gatherers.length == 0)
+		this.StartRegenerationDelayTimer();
 };
 
 Engine.RegisterComponentType(IID_ResourceSupply, "ResourceSupply", ResourceSupply);
diff --git a/binaries/data/mods/public/simulation/components/StatisticsTracker.js b/binaries/data/mods/public/simulation/components/StatisticsTracker.js
index ab87560e93..5ccb40034c 100644
--- a/binaries/data/mods/public/simulation/components/StatisticsTracker.js
+++ b/binaries/data/mods/public/simulation/components/StatisticsTracker.js
@@ -98,7 +98,10 @@ StatisticsTracker.prototype.KilledEntity = function(targetEntity)
 {
 	var cmpTargetEntityIdentity = Engine.QueryInterface(targetEntity, IID_Identity);
 	var cmpCost = Engine.QueryInterface(targetEntity, IID_Cost);
-	var costs = cmpCost.GetResourceCosts();
+    if (cmpCost)
+        var costs = cmpCost.GetResourceCosts();
+    else
+        var costs = { "food": 0, "wood": 0, "stone": 0, "metal": 0 };
 	if (cmpTargetEntityIdentity)
 	{
 		var cmpFoundation = Engine.QueryInterface(targetEntity, IID_Foundation);
@@ -110,7 +113,7 @@ StatisticsTracker.prototype.KilledEntity = function(targetEntity)
 		var targetIsCivCentre = cmpTargetEntityIdentity.HasClass("CivCentre");
 
 		var cmpTargetOwnership = Engine.QueryInterface(targetEntity, IID_Ownership);
-	    
+
 		// Don't increase counters if target player is gaia (player 0)
 		if (cmpTargetOwnership.GetOwner() != 0)
 		{
@@ -121,7 +124,7 @@ StatisticsTracker.prototype.KilledEntity = function(targetEntity)
 				{
 					this.enemyUnitsKilledValue += costs[r];
 				}
-			}	
+			}
 			if (targetIsStructure)
 			{
 				this.enemyBuildingsDestroyed++;
@@ -140,7 +143,10 @@ StatisticsTracker.prototype.LostEntity = function(lostEntity)
 {
 	var cmpLostEntityIdentity = Engine.QueryInterface(lostEntity, IID_Identity);
 	var cmpCost = Engine.QueryInterface(lostEntity, IID_Cost);
-	var costs = cmpCost.GetResourceCosts();
+    if (cmpCost)
+        var costs = cmpCost.GetResourceCosts();
+    else
+        var costs = { "food": 0, "wood": 0, "stone": 0, "metal": 0 };
 	if (cmpLostEntityIdentity)
 	{
 		var cmpFoundation = Engine.QueryInterface(lostEntity, IID_Foundation);
@@ -156,8 +162,8 @@ StatisticsTracker.prototype.LostEntity = function(lostEntity)
 			for (var r in costs)
 			{
 				this.unitsLostValue += costs[r];
-			}	
-		}	
+			}
+		}
 		if (lostEntityIsStructure)
 		{
 			this.buildingsLost++;
@@ -177,7 +183,7 @@ StatisticsTracker.prototype.LostEntity = function(lostEntity)
 StatisticsTracker.prototype.IncreaseResourceGatheredCounter = function(type, amount, specificType)
 {
 	this.resourcesGathered[type] += amount;
-	
+
 	if (type == "food" && (specificType == "fruit" || specificType == "grain"))
 		this.resourcesGathered["vegetarianFood"] += amount;
 };
diff --git a/binaries/data/mods/public/simulation/templates/gaia/flora_tree_apple.xml b/binaries/data/mods/public/simulation/templates/gaia/flora_tree_apple.xml
index 36ea1f863d..3997da45aa 100644
--- a/binaries/data/mods/public/simulation/templates/gaia/flora_tree_apple.xml
+++ b/binaries/data/mods/public/simulation/templates/gaia/flora_tree_apple.xml
@@ -12,6 +12,9 @@
   <Obstruction>
     <Unit radius="0.9"/>
   </Obstruction>
+  <Health>
+    <Max>150</Max>
+  </Health>
   <ResourceSupply>
     <Amount>400</Amount>
     <Type>food.fruit</Type>
diff --git a/binaries/data/mods/public/simulation/templates/template_gaia_flora_bush_berry.xml b/binaries/data/mods/public/simulation/templates/template_gaia_flora_bush_berry.xml
index b63d368a42..7a431d3c45 100644
--- a/binaries/data/mods/public/simulation/templates/template_gaia_flora_bush_berry.xml
+++ b/binaries/data/mods/public/simulation/templates/template_gaia_flora_bush_berry.xml
@@ -15,11 +15,28 @@
     <Type>food</Type>
     <Colour r="205" g="115" b="16"/>
   </Minimap>
+  <Health>
+    <Max>100</Max>
+    <RegenRate>0</RegenRate>
+    <DeathType>vanish</DeathType>
+    <Unhealable>true</Unhealable>
+    <Repairable>false</Repairable>
+  </Health>
+  <Armour>
+      <Hack>1.0</Hack>
+      <Pierce>1.0</Pierce>
+      <Crush>1.0</Crush>
+  </Armour>
   <ResourceSupply>
     <KillBeforeGather>false</KillBeforeGather>
     <Amount>200</Amount>
     <Type>food.fruit</Type>
-	<MaxGatherers>8</MaxGatherers>
+    <MaxGatherers>8</MaxGatherers>
+    <Regeneration>
+      <Rate>3</Rate>
+      <Delay>10</Delay>
+      <Growth>linear</Growth>
+    </Regeneration>
   </ResourceSupply>
   <Selectable>
     <EditorOnly disable=""/>
diff --git a/binaries/data/mods/public/simulation/templates/template_unit_fauna_fish.xml b/binaries/data/mods/public/simulation/templates/template_unit_fauna_fish.xml
index 35ccc69140..9719190443 100644
--- a/binaries/data/mods/public/simulation/templates/template_unit_fauna_fish.xml
+++ b/binaries/data/mods/public/simulation/templates/template_unit_fauna_fish.xml
@@ -22,7 +22,13 @@
     <KillBeforeGather>false</KillBeforeGather>
     <Amount>1000</Amount>
     <Type>food.fish</Type>
-	<MaxGatherers>4</MaxGatherers>
+    <MaxGatherers>4</MaxGatherers>
+    <Regeneration>
+      <Rate>1</Rate>
+      <Acceleration>1.03</Acceleration>
+      <Delay>5</Delay>
+      <Growth>quadratic</Growth>
+    </Regeneration>
   </ResourceSupply>
   <Selectable>
     <Overlay>
diff --git a/source/gui/CGUI.cpp b/source/gui/CGUI.cpp
index 37403929a3..b93c749271 100644
--- a/source/gui/CGUI.cpp
+++ b/source/gui/CGUI.cpp
@@ -1775,6 +1775,15 @@ void CGUI::Xeromyces_ReadScrollBarStyle(XMBElement Element, CXeromyces* pFile)
 				scrollbar.m_MinimumBarSize = f;
 		}
 		else
+		if (attr_name == "maximum_bar_size")
+		{
+			float f;
+			if (!GUI<float>::ParseString(attr_value.FromUTF8(), f))
+				LOGERROR(L"GUI: Error parsing '%hs' (\"%hs\")", attr_name.c_str(), attr_value.c_str());
+			else
+				scrollbar.m_MaximumBarSize = f;
+		}
+		else
 		if (attr_name == "sprite_button_top")
 			scrollbar.m_SpriteButtonTop = attr_value;
 		else
diff --git a/source/gui/CGUIScrollBarVertical.cpp b/source/gui/CGUIScrollBarVertical.cpp
index f5f078bff1..d8a591c68b 100644
--- a/source/gui/CGUIScrollBarVertical.cpp
+++ b/source/gui/CGUIScrollBarVertical.cpp
@@ -22,7 +22,6 @@ IGUIScrollBar
 #include "precompiled.h"
 #include "GUI.h"
 #include "CGUIScrollBarVertical.h"
-
 #include "ps/CLogger.h"
 
 
@@ -39,18 +38,22 @@ void CGUIScrollBarVertical::SetPosFromMousePos(const CPos &mouse)
 	if (!GetStyle())
 		return;
 
-	m_Pos = (m_PosWhenPressed + m_ScrollRange*(mouse.y-m_BarPressedAtPos.y)/(m_Length-GetStyle()->m_Width*2));
+	/**
+	 * Calculate the position for the top of the item being scrolled
+	 */
+	m_Pos = m_PosWhenPressed + GetMaxPos() * (mouse.y - m_BarPressedAtPos.y) / (m_Length - GetStyle()->m_Width * 2 - m_BarSize);
 }
 
 void CGUIScrollBarVertical::Draw()
 {
 	if (!GetStyle())
 	{
-		// TODO Gee: Report in error log
+		LOGWARNING(L"Attempt to draw scrollbar without a style.");
 		return;
 	}
 
-	if (GetGUI())
+	// Only draw the scrollbar if the GUI exists and there is something to scroll.
+	if (GetGUI() && GetMaxPos() != 1)
 	{
 		CRect outline = GetOuterRect();
 
@@ -79,7 +82,7 @@ void CGUIScrollBarVertical::Draw()
 			}
 			else button_top = &GetStyle()->m_SpriteButtonTop;
 
-			// figure out what sprite to use for top button
+			// figure out what sprite to use for bottom button
 			if (m_ButtonPlusHovered)
 			{
 				if (m_ButtonPlusPressed)
@@ -111,22 +114,10 @@ void CGUIScrollBarVertical::Draw()
 		}
 
 		// Draw bar
-		/*if (m_BarPressed)
-			GetGUI()->DrawSprite(GUI<>::FallBackSprite(GetStyle()->m_SpriteBarVerticalPressed, GetStyle()->m_SpriteBarVertical),
-								 0,
-								 m_Z+0.2f,
-								 GetBarRect());
-		else
-		if (m_BarHovered)
-			GetGUI()->DrawSprite(GUI<>::FallBackSprite(GetStyle()->m_SpriteBarVerticalOver, GetStyle()->m_SpriteBarVertical),
-								 0,
-								 m_Z+0.2f,
-								 GetBarRect());
-		else*/
-			GetGUI()->DrawSprite(GetStyle()->m_SpriteBarVertical,
-								 0,
-								 m_Z+0.2f,
-								 GetBarRect());
+		GetGUI()->DrawSprite(GetStyle()->m_SpriteBarVertical,
+							 0,
+							 m_Z + 0.2f,
+							 GetBarRect());
 	}
 } 
 
@@ -141,32 +132,19 @@ CRect CGUIScrollBarVertical::GetBarRect() const
 	if (!GetStyle())
 		return ret;
 
-	float size;
-	float from, to;
+	// Get from where the scroll area begins to where it ends
+	float from = m_Y;
+	float to = m_Y + m_Length - m_BarSize;
 
-	// is edge buttons used?
 	if (m_UseEdgeButtons)
 	{
-		size = (m_Length-GetStyle()->m_Width*2.f)*m_BarSize;
-		if (size < GetStyle()->m_MinimumBarSize)
-			size = GetStyle()->m_MinimumBarSize;
-
-		from = m_Y+GetStyle()->m_Width;
-		to = m_Y+m_Length-GetStyle()->m_Width-size;
-	}
-	else
-	{
-		size = m_Length*m_BarSize;
-		if (size < GetStyle()->m_MinimumBarSize)
-			size = GetStyle()->m_MinimumBarSize;
-
-		from = m_Y;
-		to = m_Y+m_Length-size;
+		from += GetStyle()->m_Width;
+		to -= GetStyle()->m_Width;
 	}
 
 	// Setup rectangle
-	ret.top = (from + (to-from)*(m_Pos/(std::max(1.f, m_ScrollRange - m_ScrollSpace))));
-	ret.bottom = ret.top+size;
+	ret.top = from + (to - from) * (m_Pos / GetMaxPos());
+	ret.bottom = ret.top + m_BarSize;
 	ret.right = m_X + ((m_RightAligned)?(0.f):(GetStyle()->m_Width));
 	ret.left = ret.right - GetStyle()->m_Width;
 
diff --git a/source/gui/CGUIScrollBarVertical.h b/source/gui/CGUIScrollBarVertical.h
index 49751a66b3..76dad8241e 100644
--- a/source/gui/CGUIScrollBarVertical.h
+++ b/source/gui/CGUIScrollBarVertical.h
@@ -74,7 +74,7 @@ public:
 	virtual void HandleMessage(SGUIMessage &Message);
 
 	/**
-	 * Set m_Pos with g_mouse_x/y input, i.e. when draggin.
+	 * Set m_Pos with g_mouse_x/y input, i.e. when dragging.
 	 */
 	virtual void SetPosFromMousePos(const CPos &mouse);
 
diff --git a/source/gui/IGUIScrollBar.cpp b/source/gui/IGUIScrollBar.cpp
index 4c7d489d27..a88410cbbe 100644
--- a/source/gui/IGUIScrollBar.cpp
+++ b/source/gui/IGUIScrollBar.cpp
@@ -21,7 +21,8 @@ IGUIScrollBar
 
 #include "precompiled.h"
 #include "GUI.h"
-
+#include "maths/MathUtil.h"
+#include "ps/CLogger.h"
 
 //-------------------------------------------------------------------
 //	IGUIScrollBar
@@ -30,7 +31,7 @@ IGUIScrollBar::IGUIScrollBar() : m_pStyle(NULL), m_pGUI(NULL),
 								 m_X(300.f), m_Y(300.f),
 								 m_ScrollRange(1.f), m_ScrollSpace(0.f), // MaxPos: not 0, due to division.
 								 m_Length(200.f), m_Width(20.f), 
-								 m_BarSize(0.5f), m_Pos(0.f),
+								 m_BarSize(0.f), m_Pos(0.f),
 								 m_UseEdgeButtons(true),
 								 m_ButtonPlusPressed(false),
 								 m_ButtonMinusPressed(false),
@@ -47,7 +48,25 @@ IGUIScrollBar::~IGUIScrollBar()
 
 void IGUIScrollBar::SetupBarSize()
 {
-	m_BarSize = std::min((float)m_ScrollSpace/(float)m_ScrollRange, 1.f);
+	float min = GetStyle()->m_MinimumBarSize;
+	float max = GetStyle()->m_MaximumBarSize;
+	float length = m_Length;
+
+	// Check for edge buttons
+	if (m_UseEdgeButtons)
+		length -= GetStyle()->m_Width * 2.f;
+
+	// Check min and max are valid
+	if (min > length)
+	{
+		LOGWARNING(L"Minimum scrollbar size of %g is larger than the total scrollbar size of %g", min, length);
+		min = 0.f;
+	}
+	if (max < min)
+		max = length;
+
+	// Clamp size to not exceed a minimum or maximum.
+	m_BarSize = clamp(length * std::min((float)m_ScrollSpace / (float)m_ScrollRange, 1.f), min, max);
 }
 
 const SGUIScrollBarStyle *IGUIScrollBar::GetStyle() const
@@ -72,8 +91,8 @@ void IGUIScrollBar::UpdatePosBoundaries()
 		m_ScrollRange < m_ScrollSpace) // <= scrolling not applicable
 		m_Pos = 0.f;
 	else
-	if (m_Pos > m_ScrollRange - m_ScrollSpace)
-		m_Pos = m_ScrollRange - m_ScrollSpace;
+	if (m_Pos > GetMaxPos())
+		m_Pos = GetMaxPos();
 }
 
 void IGUIScrollBar::HandleMessage(SGUIMessage &Message)
@@ -93,12 +112,10 @@ void IGUIScrollBar::HandleMessage(SGUIMessage &Message)
 				UpdatePosBoundaries();
 			}
 
-			CRect bar_rect = GetBarRect();
 			// check if components are being hovered
-			m_BarHovered = bar_rect.PointInside(mouse);
-
-			m_ButtonMinusHovered = HoveringButtonMinus(m_pHostObject->GetMousePos());
-			m_ButtonPlusHovered =  HoveringButtonPlus(m_pHostObject->GetMousePos());
+			m_BarHovered = GetBarRect().PointInside(mouse);
+			m_ButtonMinusHovered = HoveringButtonMinus(mouse);
+			m_ButtonPlusHovered =  HoveringButtonPlus(mouse);
 
 			if (!m_ButtonMinusHovered)
 				m_ButtonMinusPressed = false;
diff --git a/source/gui/IGUIScrollBar.h b/source/gui/IGUIScrollBar.h
index a99a3f3810..45beefbcd8 100644
--- a/source/gui/IGUIScrollBar.h
+++ b/source/gui/IGUIScrollBar.h
@@ -90,6 +90,13 @@ struct SGUIScrollBarStyle
 	 */
 	float m_MinimumBarSize;
 
+	/**
+	 * Sometimes you would like your scroll bar to have a fixed maximum size
+	 * so that the texture does not get too stretched, you can set a maximum
+	 * in pixels.
+	 */
+	float m_MaximumBarSize;
+
 	//@}
 	//--------------------------------------------------------
 	/** @name Horizontal Sprites */
@@ -199,27 +206,27 @@ public:
 	virtual void SetPos(float f) { m_Pos = f; UpdatePosBoundaries(); }
 
 	/**
-	 * Get the value of Pos that corresponds to the bottom of the scrollable region
+	 * Get the value of m_Pos that corresponds to the bottom of the scrollable region
 	 */
-	float GetMaxPos() const { return m_ScrollRange - m_ScrollSpace;	}
+	float GetMaxPos() const { return std::max(1.f, m_ScrollRange - m_ScrollSpace); }
 
 	/**
-	 * Scroll towards 1.0 one step
+	 * Increase scroll one step
 	 */
 	virtual void ScrollPlus() { m_Pos += 30.f; UpdatePosBoundaries(); }
 
 	/**
-	 * Scroll towards 0.0 one step
+	 * Decrease scroll one step
 	 */
 	virtual void ScrollMinus() { m_Pos -= 30.f; UpdatePosBoundaries(); }
 
 	/**
-	 * Scroll towards 1.0 one step
+	 * Increase scroll three steps
 	 */
 	virtual void ScrollPlusPlenty() { m_Pos += 90.f; UpdatePosBoundaries(); }
 
 	/**
-	 * Scroll towards 0.0 one step
+	 * Decrease scroll three steps
 	 */
 	virtual void ScrollMinusPlenty() { m_Pos -= 90.f; UpdatePosBoundaries(); }