Add accelerations in unit movement.

This helps preventing arrow dodging.

Differential Revision: D3200
Reviewed By: Freagarach
Comments By: wraitii, vladislav, Palaxin, Stan
refs: #5106

This was SVN commit r25953.

binaries/data/mods/public/globalscripts/Templates.js

@@ -437,10 +437,12 @@ function GetTemplateDataHelper(template, player, auraTemplates, modifiers = {})
 
 	if (template.UnitMotion)
 	{
+		const walkSpeed = getEntityValue("UnitMotion/WalkSpeed");
 		ret.speed = {
-			"walk": getEntityValue("UnitMotion/WalkSpeed"),
+			"walk": walkSpeed,
+			"run": walkSpeed,
+			"acceleration": getEntityValue("UnitMotion/Acceleration")
 		};
-		ret.speed.run = getEntityValue("UnitMotion/WalkSpeed");
 		if (template.UnitMotion.RunMultiplier)
 			ret.speed.run *= getEntityValue("UnitMotion/RunMultiplier");
 	}

binaries/data/mods/public/gui/common/tooltips.js

@@ -1005,12 +1005,13 @@ function getSpeedTooltip(template)
 	if (!template.speed)
 		return "";
 
-	let walk = template.speed.walk.toFixed(1);
+	const walk = template.speed.walk.toFixed(1);
-	let run = template.speed.run.toFixed(1);
+	const run = template.speed.run.toFixed(1);
 
 	if (walk == 0 && run == 0)
 		return "";
 
+	const acceleration = template.speed.acceleration.toFixed(1);
 	return sprintf(translate("%(label)s %(speeds)s"), {
 		"label": headerFont(translate("Speed:")),
 		"speeds":
@@ -1022,6 +1023,11 @@ function getSpeedTooltip(template)
 			sprintf(translate("%(speed)s %(movementType)s"), {
 				"speed": run,
 				"movementType": unitFont(translate("Run"))
+			}) +
+			commaFont(translate(", ")) +
+			sprintf(translate("%(speed)s %(movementType)s"), {
+				"speed": acceleration,
+				"movementType": unitFont(translate("Acceleration"))
 			})
 	});
 }

binaries/data/mods/public/simulation/components/Formation.js

@@ -895,17 +895,22 @@ Formation.prototype.ComputeMotionParameters = function()
 {
 	let maxRadius = 0;
 	let minSpeed = Infinity;
+	let minAcceleration = Infinity;
 
 	for (let ent of this.members)
 	{
 		let cmpUnitMotion = Engine.QueryInterface(ent, IID_UnitMotion);
 		if (cmpUnitMotion)
+		{
 			minSpeed = Math.min(minSpeed, cmpUnitMotion.GetWalkSpeed());
+			minAcceleration = Math.min(minAcceleration, cmpUnitMotion.GetAcceleration());
+		}
 	}
 	minSpeed *= this.GetSpeedMultiplier();
 
 	let cmpUnitMotion = Engine.QueryInterface(this.entity, IID_UnitMotion);
 	cmpUnitMotion.SetSpeedMultiplier(minSpeed / cmpUnitMotion.GetWalkSpeed());
+	cmpUnitMotion.SetAcceleration(minAcceleration);
 };
 
 Formation.prototype.ShapeUpdate = function()

binaries/data/mods/public/simulation/components/GuiInterface.js

@@ -585,7 +585,8 @@ GuiInterface.prototype.GetEntityState = function(player, ent)
 	if (cmpUnitMotion)
 		ret.speed = {
 			"walk": cmpUnitMotion.GetWalkSpeed(),
-			"run": cmpUnitMotion.GetWalkSpeed() * cmpUnitMotion.GetRunMultiplier()
+			"run": cmpUnitMotion.GetWalkSpeed() * cmpUnitMotion.GetRunMultiplier(),
+			"acceleration": cmpUnitMotion.GetAcceleration()
 		};
 
 	let cmpUpkeep = Engine.QueryInterface(ent, IID_Upkeep);

binaries/data/mods/public/simulation/components/UnitMotionFlying.js

@@ -345,6 +345,16 @@ UnitMotionFlying.prototype.GetSpeedMultiplier = function()
 	return this.speed / +this.template.MaxSpeed;
 };
 
+UnitMotionFlying.prototype.GetAcceleration = function()
+{
+	return +this.template.AccelRate;
+};
+
+UnitMotionFlying.prototype.SetAcceleration = function()
+{
+	// Acceleration is set by the template. Ignore.
+};
+
 UnitMotionFlying.prototype.GetPassabilityClassName = function()
 {
 	return this.template.PassabilityClass;

binaries/data/mods/public/simulation/components/tests/test_UnitAI.js

@@ -94,6 +94,7 @@ TestTargetEntityRenaming(
 			"MoveToTargetRange": () => true,
 			"GetRunMultiplier": () => 1,
 			"SetSpeedMultiplier": () => {},
+			"GetAcceleration": () => 1,
 			"StopMoving": () => {}
 		});
 
@@ -168,6 +169,7 @@ function TestFormationExiting(mode)
 
 	AddMock(unit, IID_UnitMotion, {
 		"GetWalkSpeed": () => 1,
+		"GetAcceleration": () => 1,
 		"MoveToFormationOffset": (target, x, z) => {},
 		"MoveToTargetRange": (target, min, max) => true,
 		"SetMemberOfFormation": () => {},
@@ -243,6 +245,7 @@ function TestFormationExiting(mode)
 		"GetWalkSpeed": () => 1,
 		"StopMoving": () => {},
 		"SetSpeedMultiplier": () => {},
+		"SetAcceleration": (accel) => {},
 		"MoveToPointRange": () => true,
 		"SetFacePointAfterMove": () => {},
 		"GetFacePointAfterMove": () => true,
@@ -348,6 +351,7 @@ function TestMoveIntoFormationWhileAttacking()
 
 		AddMock(unit + i, IID_UnitMotion, {
 			"GetWalkSpeed": () => 1,
+			"GetAcceleration": () => 1,
 			"MoveToFormationOffset": (target, x, z) => {},
 			"MoveToTargetRange": (target, min, max) => true,
 			"SetMemberOfFormation": () => {},
@@ -414,6 +418,7 @@ function TestMoveIntoFormationWhileAttacking()
 	AddMock(controller, IID_UnitMotion, {
 		"GetWalkSpeed": () => 1,
 		"SetSpeedMultiplier": (speed) => {},
+		"SetAcceleration": (accel) => {},
 		"MoveToPointRange": (x, z, minRange, maxRange) => {},
 		"StopMoving": () => {},
 		"SetFacePointAfterMove": () => {},

binaries/data/mods/public/simulation/templates/gaia/fauna_camel.xml

@@ -27,6 +27,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.45</WalkSpeed>
+    <Acceleration op="mul">0.45</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/camel.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_chicken.xml

@@ -42,6 +42,7 @@
   </UnitAI>
   <UnitMotion>
     <WalkSpeed op="mul">0.15</WalkSpeed>
+    <Acceleration op="mul">0.15</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/chicken.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_crocodile_nile.xml

@@ -47,6 +47,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.3</WalkSpeed>
+    <Acceleration op="mul">0.3</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/crocodile.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_donkey.xml

@@ -28,6 +28,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/donkey.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_giraffe.xml

@@ -20,6 +20,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.6</WalkSpeed>
+    <Acceleration op="mul">0.6</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/giraffe_adult.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_giraffe_infant.xml

@@ -20,6 +20,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.6</WalkSpeed>
+    <Acceleration op="mul">0.6</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/giraffe_baby.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_goat.xml

@@ -35,6 +35,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.45</WalkSpeed>
+    <Acceleration op="mul">0.45</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/goat.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_horse.xml

@@ -28,6 +28,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/horse.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_lion.xml

@@ -36,6 +36,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.45</WalkSpeed>
+    <Acceleration op="mul">0.45</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/lion.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_peacock.xml

@@ -40,6 +40,7 @@
   </UnitAI>
   <UnitMotion>
     <WalkSpeed op="mul">0.3</WalkSpeed>
+    <Acceleration op="mul">0.3</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/peacock.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_pig.xml

@@ -35,6 +35,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.45</WalkSpeed>
+    <Acceleration op="mul">0.45</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/pig1.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_pig_flaming.xml

@@ -29,6 +29,7 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">3.5</WalkSpeed>
+    <Acceleration op="mul">3.5</Acceleration>
   </UnitMotion>
   <Upgrade disable=""/>
   <VisualActor>

binaries/data/mods/public/simulation/templates/gaia/fauna_piglet.xml

@@ -19,6 +19,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.25</WalkSpeed>
+    <Acceleration op="mul">0.25</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/piglet.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_shark.xml

@@ -45,6 +45,7 @@
   <UnitMotion>
     <PassabilityClass>ship-small</PassabilityClass>
     <WalkSpeed op="mul">0.6</WalkSpeed>
+    <Acceleration op="mul">0.6</Acceleration>
   </UnitMotion>
   <Visibility>
     <RetainInFog>false</RetainInFog>

binaries/data/mods/public/simulation/templates/gaia/fauna_sheep.xml

@@ -35,6 +35,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.45</WalkSpeed>
+    <Acceleration op="mul">0.45</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/sheep3.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_wildebeest.xml

@@ -20,6 +20,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/wildebeest.xml</Actor>

binaries/data/mods/public/simulation/templates/gaia/fauna_zebra.xml

@@ -20,6 +20,7 @@
   </StatusBars>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>fauna/zebra.xml</Actor>

binaries/data/mods/public/simulation/templates/template_formation.xml

@@ -69,8 +69,10 @@
   </UnitAI>
   <UnitMotion>
     <FormationController>true</FormationController>
-    <WalkSpeed>1.0</WalkSpeed>
+    <WalkSpeed>1</WalkSpeed>
-    <RunMultiplier>100.0</RunMultiplier> <!-- = Max formation speed -->
+    <RunMultiplier>100</RunMultiplier> <!-- = Max formation speed -->
+    <InstantTurnAngle>0.1</InstantTurnAngle>
+    <Acceleration>100</Acceleration> <!-- Unused -->
     <PassabilityClass>large</PassabilityClass>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit.xml

@@ -123,8 +123,10 @@
   <UnitMotion>
     <FormationController>false</FormationController>
     <PassabilityClass>default</PassabilityClass>
-    <WalkSpeed>9.0</WalkSpeed>
+    <WalkSpeed>9</WalkSpeed>
     <RunMultiplier>1.67</RunMultiplier>
+    <InstantTurnAngle>1.5</InstantTurnAngle>
+    <Acceleration>18</Acceleration>
   </UnitMotion>
   <Visibility>
     <RetainInFog>false</RetainInFog>

binaries/data/mods/public/simulation/templates/template_unit_catafalque.xml

@@ -52,6 +52,7 @@
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
     <WalkSpeed op="mul">0.55</WalkSpeed>
+    <Acceleration op="mul">0.275</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>units/global/catafalque.xml</Actor>

binaries/data/mods/public/simulation/templates/template_unit_cavalry_ranged_archer.xml

@@ -36,5 +36,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.85</WalkSpeed>
+    <Acceleration op="mul">0.85</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_cavalry_ranged_crossbowman.xml

@@ -41,5 +41,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_cavalry_ranged_javelineer.xml

@@ -36,5 +36,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_cavalry_archer.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.85</WalkSpeed>
+    <Acceleration op="mul">0.85</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_cavalry_crossbowman.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_cavalry_javelineer.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_elephant.xml

@@ -55,6 +55,7 @@
   </StatusBars>
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
+    <Acceleration op="mul">0.5</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>100</Range>

binaries/data/mods/public/simulation/templates/template_unit_champion_infantry_archer.xml

@@ -46,5 +46,6 @@
   <Turretable/>
   <UnitMotion>
     <WalkSpeed op="add">1.2</WalkSpeed>
+    <Acceleration op="add">2.4</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_infantry_crossbowman.xml

@@ -46,5 +46,6 @@
   <Turretable/>
   <UnitMotion>
     <WalkSpeed op="add">0.6</WalkSpeed>
+    <Acceleration op="add">1.2</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_infantry_javelineer.xml

@@ -46,5 +46,6 @@
   <Turretable/>
   <UnitMotion>
     <WalkSpeed op="mul">1.2</WalkSpeed>
+    <Acceleration op="mul">1.2</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_champion_infantry_pikeman.xml

@@ -46,5 +46,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_dog.xml

@@ -67,6 +67,7 @@
   <UnitMotion>
     <WalkSpeed op="mul">1.5</WalkSpeed>
     <RunMultiplier>2</RunMultiplier>
+    <Acceleration op="mul">1.5</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>30</Range>

binaries/data/mods/public/simulation/templates/template_unit_elephant.xml

@@ -54,6 +54,7 @@
   </StatusBars>
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
+    <Acceleration op="mul">0.5</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>100</Range>

binaries/data/mods/public/simulation/templates/template_unit_fauna.xml

@@ -46,6 +46,7 @@
   </UnitAI>
   <UnitMotion>
     <WalkSpeed op="mul">0.7</WalkSpeed>
+    <Acceleration op="mul">0.7</Acceleration>
   </UnitMotion>
   <Visibility>
     <RetainInFog>true</RetainInFog>

binaries/data/mods/public/simulation/templates/template_unit_fauna_herd_domestic_cattle.xml

@@ -11,5 +11,6 @@
   <UnitMotion>
     <WalkSpeed op="mul">0.4</WalkSpeed>
     <RunMultiplier>1.4</RunMultiplier>
+    <Acceleration op="mul">0.4</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_fauna_hunt_defensive_bull.xml

@@ -16,5 +16,6 @@
     <PassabilityClass>large</PassabilityClass>
     <WalkSpeed op="mul">0.4</WalkSpeed>
     <RunMultiplier>2.0</RunMultiplier>
+    <Acceleration op="mul">0.4</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_fauna_hunt_defensive_elephant.xml

@@ -21,5 +21,6 @@
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
     <WalkSpeed op="mul">0.5</WalkSpeed>
+    <Acceleration op="mul">0.25</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_fauna_hunt_whale.xml

@@ -55,5 +55,6 @@
     <PassabilityClass>ship-small</PassabilityClass>
     <WalkSpeed op="mul">1.8</WalkSpeed>
     <RunMultiplier>1</RunMultiplier>
+    <Acceleration op="mul">1.8</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_fauna_wild_aggressive_dog.xml

@@ -14,5 +14,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">1.6</WalkSpeed>
+    <Acceleration op="mul">1.6</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_hero_cavalry_archer.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.85</WalkSpeed>
+    <Acceleration op="mul">0.85</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_hero_cavalry_crossbowman.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_hero_cavalry_javelineer.xml

@@ -42,5 +42,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_hero_elephant_melee.xml

@@ -73,5 +73,6 @@
   </StatusBars>
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
+    <Acceleration op="mul">0.5</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_infantry_melee_pikeman.xml

@@ -50,5 +50,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_infantry_ranged_archer.xml

@@ -48,5 +48,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="add">1.2</WalkSpeed>
+    <Acceleration op="add">2.4</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_infantry_ranged_crossbowman.xml

@@ -49,5 +49,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="add">0.6</WalkSpeed>
+    <Acceleration op="add">1.2</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_infantry_ranged_javelineer.xml

@@ -47,5 +47,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="add">2.4</WalkSpeed>
+    <Acceleration op="add">4.8</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_infantry_ranged_slinger.xml

@@ -49,5 +49,6 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">1.2</WalkSpeed>
+    <Acceleration op="mul">1.2</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_ship.xml

@@ -73,5 +73,7 @@
   <TreasureCollector disable=""/>
   <UnitMotion>
     <PassabilityClass>ship</PassabilityClass>
+    <InstantTurnAngle>0.5</InstantTurnAngle>
+    <Acceleration op="mul">0.25</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_ship_bireme.xml

@@ -59,6 +59,7 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">1.55</WalkSpeed>
+    <Acceleration op="mul">1.55</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>90</Range>

binaries/data/mods/public/simulation/templates/template_unit_ship_fire.xml

@@ -47,6 +47,7 @@
   <UnitMotion>
     <PassabilityClass>ship-small</PassabilityClass>
     <WalkSpeed op="mul">1.6</WalkSpeed>
+    <Acceleration op="mul">1.6</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>60</Range>

binaries/data/mods/public/simulation/templates/template_unit_ship_fishing.xml

@@ -71,6 +71,7 @@
   <UnitMotion>
     <PassabilityClass>ship-small</PassabilityClass>
     <WalkSpeed op="mul">1.1</WalkSpeed>
+    <Acceleration op="mul">1.1</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>30</Range>

binaries/data/mods/public/simulation/templates/template_unit_ship_merchant.xml

@@ -39,6 +39,7 @@
   <UnitMotion>
     <PassabilityClass>ship-small</PassabilityClass>
     <WalkSpeed op="mul">1.35</WalkSpeed>
+    <Acceleration op="mul">1.6</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>50</Range>

binaries/data/mods/public/simulation/templates/template_unit_ship_quinquereme.xml

@@ -67,6 +67,7 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">1.8</WalkSpeed>
+    <Acceleration op="mul">1.8</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>110</Range>

binaries/data/mods/public/simulation/templates/template_unit_ship_trireme.xml

@@ -62,6 +62,7 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">1.8</WalkSpeed>
+    <Acceleration op="mul">1.8</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>90</Range>

binaries/data/mods/public/simulation/templates/template_unit_siege.xml

@@ -60,5 +60,7 @@
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
     <RunMultiplier>1</RunMultiplier>
+    <InstantTurnAngle>0.75</InstantTurnAngle>
+    <Acceleration op="mul">0.25</Acceleration>
   </UnitMotion>
 </Entity>

binaries/data/mods/public/simulation/templates/template_unit_siege_boltshooter.xml

@@ -71,6 +71,7 @@
   </UnitAI>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>100</Range>

binaries/data/mods/public/simulation/templates/template_unit_siege_ram.xml

@@ -59,6 +59,7 @@
   </Sound>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>80</Range>

binaries/data/mods/public/simulation/templates/template_unit_siege_stonethrower.xml

@@ -64,6 +64,7 @@
   </UnitAI>
   <UnitMotion>
     <WalkSpeed op="mul">0.8</WalkSpeed>
+    <Acceleration op="mul">0.8</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>100</Range>

binaries/data/mods/public/simulation/templates/template_unit_siege_tower.xml

@@ -95,6 +95,7 @@
   </Resistance>
   <UnitMotion>
     <WalkSpeed op="mul">0.7</WalkSpeed>
+    <Acceleration op="mul">0.7</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>80</Range>

binaries/data/mods/public/simulation/templates/template_unit_support_elephant.xml

@@ -70,6 +70,7 @@
   <UnitMotion>
     <PassabilityClass>large</PassabilityClass>
     <WalkSpeed op="mul">0.6</WalkSpeed>
+    <Acceleration op="mul">0.3</Acceleration>
   </UnitMotion>
   <Vision>
     <Range>50</Range>

binaries/data/mods/public/simulation/templates/units/brit/ship_trireme.xml

@@ -23,6 +23,7 @@
   </Loot>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>structures/celts/warship.xml</Actor>

binaries/data/mods/public/simulation/templates/units/gaul/champion_fanatic.xml

@@ -17,6 +17,7 @@
   </Resistance>
   <UnitMotion>
     <WalkSpeed op="mul">1.4</WalkSpeed>
+    <Acceleration op="mul">1.4</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>units/gauls/infantry_spearman_c.xml</Actor>

binaries/data/mods/public/simulation/templates/units/gaul/ship_trireme.xml

@@ -23,6 +23,7 @@
   </Loot>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>structures/celts/warship.xml</Actor>

binaries/data/mods/public/simulation/templates/units/iber/ship_trireme.xml

@@ -24,6 +24,7 @@
   </Loot>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>structures/iberians/warship.xml</Actor>

binaries/data/mods/public/simulation/templates/units/maur/ship_trireme.xml

@@ -23,6 +23,7 @@
   </Loot>
   <UnitMotion>
     <WalkSpeed op="mul">0.9</WalkSpeed>
+    <Acceleration op="mul">0.9</Acceleration>
   </UnitMotion>
   <VisualActor>
     <Actor>structures/mauryas/trireme.xml</Actor>

binaries/data/mods/public/simulation/templates/units/rome/champion_infantry_spear_gladiator.xml

@@ -36,6 +36,7 @@
   </TrainingRestrictions>
   <UnitMotion>
     <WalkSpeed op="mul">1.5</WalkSpeed>
+    <Acceleration op="mul">1.5</Acceleration>
   </UnitMotion>
   <Vision>
     <Range op="mul">0.5</Range>

binaries/data/mods/public/simulation/templates/units/rome/champion_infantry_sword_gladiator.xml

@@ -37,6 +37,7 @@
   </TrainingRestrictions>
   <UnitMotion>
     <WalkSpeed op="mul">1.4</WalkSpeed>
+    <Acceleration op="mul">1.4</Acceleration>
   </UnitMotion>
   <Vision>
     <Range op="mul">0.5</Range>

source/simulation2/components/CCmpUnitMotion.h

@@ -153,7 +153,7 @@ public:
 
 	bool m_IsFormationController;
 
-	fixed m_TemplateWalkSpeed, m_TemplateRunMultiplier;
+	fixed m_TemplateWalkSpeed, m_TemplateRunMultiplier, m_TemplateAcceleration;
 	pass_class_t m_PassClass;
 	std::string m_PassClassName;
 
@@ -225,8 +225,12 @@ public:
 	// This caches the resulting speed from m_WalkSpeed * m_SpeedMultiplier for convenience.
 	fixed m_Speed;
 
-	// Current mean speed (over the last turn).
+	// The speed achieved at the end of the current turn.
-	fixed m_CurSpeed;
+	fixed m_CurrentSpeed;
+
+	fixed m_InstantTurnAngle;
+
+	fixed m_Acceleration;
 
 	// Currently active paths (storing waypoints in reverse order).
 	// The last item in each path is the point we're currently heading towards.
@@ -244,15 +248,21 @@ public:
 			"<element name='FormationController'>"
 				"<data type='boolean'/>"
 			"</element>"
-			"<element name='WalkSpeed' a:help='Basic movement speed (in metres per second)'>"
+			"<element name='WalkSpeed' a:help='Basic movement speed (in metres per second).'>"
 				"<ref name='positiveDecimal'/>"
 			"</element>"
 			"<optional>"
-				"<element name='RunMultiplier' a:help='How much faster the unit goes when running (as a multiple of walk speed)'>"
+				"<element name='RunMultiplier' a:help='How much faster the unit goes when running (as a multiple of walk speed).'>"
 					"<ref name='positiveDecimal'/>"
 				"</element>"
 			"</optional>"
-			"<element name='PassabilityClass' a:help='Identifies the terrain passability class (values are defined in special/pathfinder.xml)'>"
+			"<element name='InstantTurnAngle' a:help='Angle we can turn instantly. Any value greater than pi will disable turning times. Avoid zero since it stops the entity every turn.'>"
+				"<ref name='positiveDecimal'/>"
+			"</element>"
+			"<element name='Acceleration' a:help='Acceleration (in metres per second^2).'>"
+				"<ref name='positiveDecimal'/>"
+			"</element>"
+			"<element name='PassabilityClass' a:help='Identifies the terrain passability class (values are defined in special/pathfinder.xml).'>"
 				"<text/>"
 			"</element>"
 			"<optional>"
@@ -270,12 +280,16 @@ public:
 
 		m_WalkSpeed = m_TemplateWalkSpeed = m_Speed = paramNode.GetChild("WalkSpeed").ToFixed();
 		m_SpeedMultiplier = fixed::FromInt(1);
-		m_CurSpeed = fixed::Zero();
+		m_CurrentSpeed = fixed::Zero();
 
 		m_RunMultiplier = m_TemplateRunMultiplier = fixed::FromInt(1);
 		if (paramNode.GetChild("RunMultiplier").IsOk())
 			m_RunMultiplier = m_TemplateRunMultiplier = paramNode.GetChild("RunMultiplier").ToFixed();
 
+		m_InstantTurnAngle = paramNode.GetChild("InstantTurnAngle").ToFixed();
+
+		m_Acceleration = m_TemplateAcceleration = paramNode.GetChild("Acceleration").ToFixed();
+
 		CmpPtr<ICmpPathfinder> cmpPathfinder(GetSystemEntity());
 		if (cmpPathfinder)
 		{
@@ -322,7 +336,11 @@ public:
 
 		serialize.NumberFixed_Unbounded("speed multiplier", m_SpeedMultiplier);
 
-		serialize.NumberFixed_Unbounded("current speed", m_CurSpeed);
+		serialize.NumberFixed_Unbounded("current speed", m_CurrentSpeed);
+
+		serialize.NumberFixed_Unbounded("instant turn angle", m_InstantTurnAngle);
+
+		serialize.NumberFixed_Unbounded("acceleration", m_Acceleration);
 
 		serialize.Bool("facePointAfterMove", m_FacePointAfterMove);
 		serialize.Bool("pushing", m_Pushing);
@@ -456,15 +474,25 @@ public:
 
 		CFixedVector2D pos = cmpPosition->GetPosition2D();
 		entity_angle_t angle = cmpPosition->GetRotation().Y;
-
+		fixed speed = m_CurrentSpeed;
 		// Copy the path so we don't change it.
 		WaypointPath shortPath = m_ShortPath;
 		WaypointPath longPath = m_LongPath;
 
-		PerformMove(dt, cmpPosition->GetTurnRate(), shortPath, longPath, pos, angle);
+		PerformMove(dt, cmpPosition->GetTurnRate(), shortPath, longPath, pos, speed, angle);
 		return pos;
 	}
 
+	virtual fixed GetAcceleration() const
+	{
+		return m_Acceleration;
+	}
+
+	virtual void SetAcceleration(fixed acceleration)
+	{
+		m_Acceleration = acceleration;
+	}
+
 	virtual pass_class_t GetPassabilityClass() const
 	{
 		return m_PassClass;
@@ -485,7 +513,7 @@ public:
 
 	virtual fixed GetCurrentSpeed() const
 	{
-		return m_CurSpeed;
+		return m_CurrentSpeed;
 	}
 
 	virtual void SetFacePointAfterMove(bool facePointAfterMove)
@@ -721,13 +749,13 @@ private:
 	 * This does not send actually change the position.
 	 * @returns true if the move was obstructed.
 	 */
-	bool PerformMove(fixed dt, const fixed& turnRate, WaypointPath& shortPath, WaypointPath& longPath, CFixedVector2D& pos, entity_angle_t& angle) const;
+	bool PerformMove(fixed dt, const fixed& turnRate, WaypointPath& shortPath, WaypointPath& longPath, CFixedVector2D& pos, fixed& speed, entity_angle_t& angle) const;
 
 	/**
 	 * Update other components on our speed.
 	 * (For performance, this should try to avoid sending messages).
 	 */
-	void UpdateMovementState(entity_pos_t speed);
+	void UpdateMovementState(entity_pos_t speed, entity_pos_t meanSpeed);
 
 	/**
 	 * React if our move was obstructed.
@@ -993,7 +1021,7 @@ void CCmpUnitMotion::PreMove(CCmpUnitMotionManager::MotionState& state)
 
 	// If we were idle and will still be, no need for an update.
 	state.needUpdate = state.cmpPosition->IsInWorld() &&
-		(m_CurSpeed != fixed::Zero() || m_MoveRequest.m_Type != MoveRequest::NONE);
+		(m_CurrentSpeed != fixed::Zero() || m_MoveRequest.m_Type != MoveRequest::NONE);
 
 	if (!m_BlockMovement)
 		return;
@@ -1017,7 +1045,7 @@ void CCmpUnitMotion::Move(CCmpUnitMotionManager::MotionState& state, fixed dt)
 	// to it, then throw away our current path and go straight to it.
 	state.wentStraight = TryGoingStraightToTarget(state.initialPos, true);
 
-	state.wasObstructed = PerformMove(dt, state.cmpPosition->GetTurnRate(), m_ShortPath, m_LongPath, state.pos, state.angle);
+	state.wasObstructed = PerformMove(dt, state.cmpPosition->GetTurnRate(), m_ShortPath, m_LongPath, state.pos, state.speed, state.angle);
 }
 
 void CCmpUnitMotion::PostMove(CCmpUnitMotionManager::MotionState& state, fixed dt)
@@ -1027,7 +1055,7 @@ void CCmpUnitMotion::PostMove(CCmpUnitMotionManager::MotionState& state, fixed d
 	{
 		if (state.angle != state.initialAngle)
 			state.cmpPosition->TurnTo(state.angle);
-		UpdateMovementState(fixed::Zero());
+		UpdateMovementState(fixed::Zero(), fixed::Zero());
 	}
 	else
 	{
@@ -1041,7 +1069,7 @@ void CCmpUnitMotion::PostMove(CCmpUnitMotionManager::MotionState& state, fixed d
 		state.cmpPosition->MoveAndTurnTo(state.pos.X, state.pos.Y, state.angle);
 
 		// Calculate the mean speed over this past turn.
-		UpdateMovementState(offset.Length() / dt);
+		UpdateMovementState(state.speed, offset.Length() / dt);
 	}
 
 	if (state.wasObstructed && HandleObstructedMove(state.pos != state.initialPos))
@@ -1094,7 +1122,7 @@ bool CCmpUnitMotion::PossiblyAtDestination() const
 	return false;
 }
 
-bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath& shortPath, WaypointPath& longPath, CFixedVector2D& pos, entity_angle_t& angle) const
+bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath& shortPath, WaypointPath& longPath, CFixedVector2D& pos, fixed& speed, entity_angle_t& angle) const
 {
 	// If there are no waypoint, behave as though we were obstructed and let HandleObstructedMove handle it.
 	if (shortPath.m_Waypoints.empty() && longPath.m_Waypoints.empty())
@@ -1151,21 +1179,26 @@ bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath&
 			target = CFixedVector2D(shortPath.m_Waypoints.back().x, shortPath.m_Waypoints.back().z);
 
 		CFixedVector2D offset = target - pos;
-		if (turnRate > zero && !offset.IsZero())
+
+		fixed angleDiff = angle - atan2_approx(offset.X, offset.Y);
+		fixed absoluteAngleDiff = angleDiff.Absolute();
+		if (absoluteAngleDiff > entity_angle_t::Pi())
+			absoluteAngleDiff = entity_angle_t::Pi() * 2 - absoluteAngleDiff;
+
+		// We only rotate to the instantTurnAngle angle. The rest we rotate during movement.
+		if (absoluteAngleDiff > m_InstantTurnAngle)
 		{
-			fixed maxRotation = turnRate.Multiply(timeLeft);
+			// Stop moving when rotating this far.
-			fixed angleDiff = angle - atan2_approx(offset.X, offset.Y);
+			speed = zero;
-			if (angleDiff != zero)
+			if (turnRate > zero && !offset.IsZero())
 			{
-				fixed absoluteAngleDiff = angleDiff.Absolute();
+				fixed maxRotation = turnRate.Multiply(timeLeft);
-				if (absoluteAngleDiff > entity_angle_t::Pi())
-					absoluteAngleDiff = entity_angle_t::Pi() * 2 - absoluteAngleDiff;
 
 				// Figure out whether rotating will increase or decrease the angle, and how far we need to rotate in that direction.
 				int direction = (entity_angle_t::Zero() < angleDiff && angleDiff <= entity_angle_t::Pi()) || angleDiff < -entity_angle_t::Pi() ? -1 : 1;
 
 				// Can't rotate far enough, just rotate in the correct direction.
-				if (absoluteAngleDiff > maxRotation)
+				if (absoluteAngleDiff - m_InstantTurnAngle > maxRotation)
 				{
 					angle += maxRotation * direction;
 					if (angle * direction > entity_angle_t::Pi())
@@ -1174,13 +1207,21 @@ bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath&
 				}
 				// Rotate towards the next waypoint and continue moving.
 				angle = atan2_approx(offset.X, offset.Y);
-				// Give some 'free' rotation for angles below 0.5 radians.
+				timeLeft = std::min(maxRotation, maxRotation - absoluteAngleDiff + m_InstantTurnAngle) / turnRate;
-				timeLeft = (std::min(maxRotation, maxRotation - absoluteAngleDiff + fixed::FromInt(1)/2)) / turnRate;
 			}
 		}
+		else
+		{
+			// Modify the speed depending on the angle difference.
+			fixed sin, cos;
+			sincos_approx(angleDiff, sin, cos);
+			speed = speed.Multiply(cos);
+		}
 
 		// Work out how far we can travel in timeLeft.
-		fixed maxdist = maxSpeed.Multiply(timeLeft);
+		fixed accelTime = std::min(timeLeft, (maxSpeed - speed) / m_Acceleration);
+		fixed accelDist = speed.Multiply(accelTime) + accelTime.Square().Multiply(m_Acceleration) / 2;
+		fixed maxdist = accelDist + maxSpeed.Multiply(timeLeft - accelTime);
 
 		// If the target is close, we can move there directly.
 		fixed offsetLength = offset.Length();
@@ -1191,7 +1232,20 @@ bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath&
 				pos = target;
 
 				// Spend the rest of the time heading towards the next waypoint.
-				timeLeft = (maxdist - offsetLength) / maxSpeed;
+				// Either we still need to accelerate after, or we have reached maxSpeed.
+ 				// The former is much less likely than the latter: usually we can reach
+				// maxSpeed within one waypoint. So the Sqrt is not too bad.
+				if (offsetLength <= accelDist)
+				{
+					fixed requiredTime = (-speed + (speed.Square() + offsetLength.Multiply(m_Acceleration).Multiply(fixed::FromInt(2))).Sqrt()) / m_Acceleration;
+					timeLeft -= requiredTime;
+					speed += m_Acceleration.Multiply(requiredTime);
+				}
+				else
+				{
+					timeLeft -= accelTime + (offsetLength - accelDist) / maxSpeed;
+					speed = maxSpeed;
+				}
 
 				if (shortPath.m_Waypoints.empty())
 					longPath.m_Waypoints.pop_back();
@@ -1212,6 +1266,8 @@ bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath&
 			offset.Normalize(maxdist);
 			target = pos + offset;
 
+			speed = std::min(maxSpeed, speed + m_Acceleration.Multiply(timeLeft));
+
 			if (cmpPathfinder->CheckMovement(GetObstructionFilter(specificIgnore), pos.X, pos.Y, target.X, target.Y, m_Clearance, m_PassClass))
 				pos = target;
 			else
@@ -1223,18 +1279,18 @@ bool CCmpUnitMotion::PerformMove(fixed dt, const fixed& turnRate, WaypointPath&
 	return false;
 }
 
-void CCmpUnitMotion::UpdateMovementState(entity_pos_t speed)
+void CCmpUnitMotion::UpdateMovementState(entity_pos_t speed, entity_pos_t meanSpeed)
 {
 	CmpPtr<ICmpVisual> cmpVisual(GetEntityHandle());
 	if (cmpVisual)
 	{
-		if (speed == fixed::Zero())
+		if (meanSpeed == fixed::Zero())
 			cmpVisual->SelectMovementAnimation("idle", fixed::FromInt(1));
 		else
-			cmpVisual->SelectMovementAnimation(speed > (m_WalkSpeed / 2).Multiply(m_RunMultiplier + fixed::FromInt(1)) ? "run" : "walk", speed);
+			cmpVisual->SelectMovementAnimation(meanSpeed > (m_WalkSpeed / 2).Multiply(m_RunMultiplier + fixed::FromInt(1)) ? "run" : "walk", meanSpeed);
 	}
 
-	m_CurSpeed = speed;
+	m_CurrentSpeed = speed;
 }
 
 bool CCmpUnitMotion::HandleObstructedMove(bool moved)

source/simulation2/components/CCmpUnitMotionManager.h

@@ -60,6 +60,8 @@ public:
 		// Accumulated "pushing" from nearby units.
 		CFixedVector2D push;
 
+		fixed speed;
+
 		fixed initialAngle;
 		fixed angle;
 

source/simulation2/components/CCmpUnitMotion_System.cpp

@@ -167,6 +167,7 @@ void CCmpUnitMotionManager::Move(EntityMap<MotionState>& ents, fixed dt)
 		it->second.initialPos = it->second.cmpPosition->GetPosition2D();
 		it->second.initialAngle = it->second.cmpPosition->GetRotation().Y;
 		it->second.pos = it->second.initialPos;
+		it->second.speed = it->second.cmpUnitMotion->GetCurrentSpeed();
 		it->second.angle = it->second.initialAngle;
 		ENSURE(it->second.pos.X.ToInt_RoundToZero() / PUSHING_GRID_SIZE < m_MovingUnits.width() &&
 			   it->second.pos.Y.ToInt_RoundToZero() / PUSHING_GRID_SIZE < m_MovingUnits.height());

source/simulation2/components/ICmpUnitMotion.cpp

@@ -37,6 +37,8 @@ DEFINE_INTERFACE_METHOD("GetWalkSpeed", ICmpUnitMotion, GetWalkSpeed)
 DEFINE_INTERFACE_METHOD("GetRunMultiplier", ICmpUnitMotion, GetRunMultiplier)
 DEFINE_INTERFACE_METHOD("EstimateFuturePosition", ICmpUnitMotion, EstimateFuturePosition)
 DEFINE_INTERFACE_METHOD("SetSpeedMultiplier", ICmpUnitMotion, SetSpeedMultiplier)
+DEFINE_INTERFACE_METHOD("GetAcceleration", ICmpUnitMotion, GetAcceleration)
+DEFINE_INTERFACE_METHOD("SetAcceleration", ICmpUnitMotion, SetAcceleration)
 DEFINE_INTERFACE_METHOD("GetPassabilityClassName", ICmpUnitMotion, GetPassabilityClassName)
 DEFINE_INTERFACE_METHOD("GetUnitClearance", ICmpUnitMotion, GetUnitClearance)
 DEFINE_INTERFACE_METHOD("SetFacePointAfterMove", ICmpUnitMotion, SetFacePointAfterMove)
@@ -124,6 +126,16 @@ public:
 		return m_Script.Call<CFixedVector2D>("EstimateFuturePosition", dt);
 	}
 
+	virtual fixed GetAcceleration() const
+	{
+		return m_Script.Call<fixed>("GetAcceleration");
+	}
+
+	virtual void SetAcceleration(fixed acceleration)
+	{
+		m_Script.CallVoid("SetAcceleration", acceleration);
+	}
+
 	virtual void SetFacePointAfterMove(bool facePointAfterMove)
 	{
 		m_Script.CallVoid("SetFacePointAfterMove", facePointAfterMove);

source/simulation2/components/ICmpUnitMotion.h

@@ -87,7 +87,7 @@ public:
 	virtual void StopMoving() = 0;
 
 	/**
-	 * Get the distance travelled over the last turn.
+	 * Get the speed at the end of the current turn.
 	 */
 	virtual fixed GetCurrentSpeed() const = 0;
 
@@ -129,6 +129,17 @@ public:
 	 */
 	virtual CFixedVector2D EstimateFuturePosition(const fixed dt) const = 0;
 
+	/**
+	 * Get the current acceleration.
+	 */
+	virtual fixed GetAcceleration() const = 0;
+
+	/**
+	 * Set the current acceleration.
+	 * @param acceleration The acceleration.
+	 */
+	virtual void SetAcceleration(fixed acceleration) = 0;
+
 	/**
 	 * Set whether the unit will turn to face the target point after finishing moving.
 	 */