Deterministic Simulation

CHANGELOG.md

@@ -146,6 +146,15 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - `RealTimeLimitProgress` and `SimTimeLimitProgress` on `Timer` are now both writable properties in Lua, and not only readable.
 
+- New launch arguments for running the game without anyone at the controls:  
+	`-headless` runs it with a hidden window and no drawing, with the audio going on as usual but not played to anyone, and with the simulation going as fast as it can instead of in real time.  
+	`-activity <class name> <preset name> <scene name>` and `-save <save name>` skip the menus and launch straight into an Activity or a saved game.  
+	`-sim-updates <count>` quits after that many simulation updates.
+
+- New determinism checker, for finding where two runs of the simulation stop matching. The launch argument `-determinism-record <file>` writes checkpoints of the simulation's state to a trace file as it goes, and `-determinism-verify <file>` checks a run against such a file, reporting the first checkpoint that doesn't match and quitting with a failure code. `Tools/determinism_test.py` runs missions this way and compares the runs.
+
+- New `Settings.ini` property `DisableCrashDialogs = 0/1`. With it on, the game still logs an abort, a failed assert or an unhandled exception, but then quits without showing a dialog. This is for when the game is being run by something automated.
+
 - New `Settings.ini` property `LaunchMinimised = 0/1` to have the game window start out minimised, so that launching the game doesn't take input focus or cover other windows. Disabled by default.
 
 </details>
@@ -222,6 +231,14 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - Updated SDL2 to SDL3
 
+- Much of what made two runs of the same mission play out differently is gone. Scripts on a Lua state now run in order of `UniqueID`, objects added by several threads at once get added in order of `UniqueID`, AI and drawing and audio code no longer use the simulation's random numbers, and pathfinding updates go by simulation time instead of real time.
+
+- The `UniqueID` of a `MovableObject` is now 64 bit, with its upper bits saying which thread it was made on. Scripts still get it as a number, but it can be a lot larger than it used to be.
+
+- LuaJIT now goes through a table that has tables, functions or userdata for keys in an order that doesn't depend on where those are in memory, so `pairs` gives the same order every run. This only holds on 64 bit x86 and ARM.
+
+- Numbers saved with `Activity:SaveNumber()` are now kept as doubles instead of floats, and floating point numbers in INI and save files are written out exactly instead of being rounded to 6 digits.
+
 </details>
 
 <details><summary><b>Fixed</b></summary>
@@ -266,12 +283,18 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 - Fixed an issue where if the first objects in the buy cart are items instead of an actor, they would be added to the first actor's inventory- even if it was an actor without an inventory (i.e a crab)
 
+- Fixed the option to mute audio when the game window loses focus starting out with a garbage value, which then got written to `Settings.ini`.
+
+- Fixed objects sometimes getting a garbage velocity when the terrain they hit was removed before they got to try and penetrate it, for example by a script's `OnCollideWithTerrain`.
+
 - Fixed a macOS worker-thread message box that could hang, and a libc++ build error formatting save-game timestamps.
 
 - Fixed a divide-by-zero on `AtomGroup` segments with no steps, which could feed bad values into the physics.
 
 - Fixed a couple of uninitialized values (Atom step state and the simulation frame counter) that could cause inconsistent behavior between runs.
 
+- Fixed the Techion Nanolyzer never playing its dissipate sound.
+
 - Fixed `AHuman:EquipShieldInBGArm()` being able to take the wrong item out of the inventory, which left the device it equipped both held and in the inventory. The device then got dropped twice when its holder died, and the game could crash when quitting.
 
 </details>

Data/Base.rte/AI/HumanBehaviors.lua

@@ -1706,7 +1706,7 @@ function HumanBehaviors.ShootArea(AI, Owner, Abort)
 		if Owner.FirearmIsReady then
 			AI.deviceState = AHuman.AIMING;
 			AI.Ctrl.AnalogAim = Vector(1,0):RadRotate(aim+aimError+RangeRand(-0.02, 0.02)*AI.aimSkill);
-			if ShootTimer:IsPastRealMS(aimTime) then
+			if ShootTimer:IsPastSimMS(aimTime) then
 				if Weapon.FullAuto then
 					AI.fire = true;
 				else
@@ -1732,7 +1732,7 @@ function HumanBehaviors.ShootArea(AI, Owner, Abort)
 		local _ai, _ownr, _abrt = coroutine.yield(); -- wait until next frame
 		if _abrt then return true end
 
-		if AI.UnseenTarget and CheckTargetTimer:IsPastRealMS(400*AI.aimSkill) then
+		if AI.UnseenTarget and CheckTargetTimer:IsPastSimMS(400*AI.aimSkill) then
 			if MovableMan:ValidMO(AI.UnseenTarget) and (AI.UnseenTarget.ClassName == "AHuman" or AI.UnseenTarget.ClassName == "ACrab") then
 				CheckTargetTimer:Reset();
 				if AI.UnseenTarget:GetController() and AI.UnseenTarget:GetController():IsState(Controller.WEAPON_FIRE) then

Data/Base.rte/Actors/Mecha/AADrone/AADrone.lua

@@ -140,6 +140,8 @@ function Update(self)
 			self.SAM = nil
 		end
 	elseif self.Frame > 0 and self.Vel.Largest < 12 then -- we have SAMs left
+		-- Look from above the drone. Not from AboveHUDPos, since that goes by how the HUD was last drawn, which can't be allowed to change the simulation
+		local ScanPos = self.Pos + Vector(0, -self.Height * 0.5 - 6)
 		if #self.ValidTargets < 1 then -- Find valid targets
 			if self.SearchTimer:IsPastSimMS(100) then
 				self.SearchTimer:Reset() -- Only search a few times/sec to reduce calculations per update
@@ -148,7 +150,7 @@ function Update(self)
 				local Trace = self:RotateOffset(Vector(0, -200))
 				if not SceneMan:CastStrengthRay(self.Pos, Trace, 5, Vector(), 9, -1, true) then -- Terrain str 5
 					local obstructed = false
-					local ID = SceneMan:CastMORay(self.AboveHUDPos, Trace, self.ID, self.IgnoresWhichTeam, 0, true, 15)
+					local ID = SceneMan:CastMORay(ScanPos, Trace, self.ID, self.IgnoresWhichTeam, 0, true, 15)
 					if ID < rte.NoMOID then
 						local MO = MovableMan:GetMOFromID(ID)
 						if ID ~= MO.RootID then
@@ -215,7 +217,7 @@ function Update(self)
 		else -- Check if the missile have a clear line of sight to any of the selected targets
 			local NewTarget = table.remove(self.ValidTargets).Actor -- Only check one target to reduce calculations per update
 			if NewTarget and MovableMan:ValidMO(NewTarget) and not NewTarget:IsDead() then
-				local Trace = SceneMan:ShortestDistance(self.AboveHUDPos, NewTarget.Pos, false)
+				local Trace = SceneMan:ShortestDistance(ScanPos, NewTarget.Pos, false)
 				-- Don't shoot at targets that are out of reach
 				if Trace.Magnitude < self.radarRange then
 					-- Don't shoot at targets that are very close to the brain
@@ -227,7 +229,7 @@ function Update(self)
 						-- First do a very inexact scan of half the distance to the target for friendly dropships and terrain
 						if
 							SceneMan:CastObstacleRay(
-								self.AboveHUDPos,
+								ScanPos,
 								Trace * 0.5,
 								Vector(),
 								Vector(),
@@ -238,7 +240,7 @@ function Update(self)
 							) < 0
 						then
 							-- If nothing was found, do a more exact scan for terrain all the way to the target
-							if not SceneMan:CastStrengthRay(self.AboveHUDPos, Trace, 5, Vector(), 9, -1, true) then -- Terrain str 5
+							if not SceneMan:CastStrengthRay(ScanPos, Trace, 5, Vector(), 9, -1, true) then -- Terrain str 5
 								self.SearchTimer:Reset()
 
 								-- Spawn the SAM

Data/Base.rte/Actors/Mecha/Medic/Medic.lua

@@ -50,7 +50,8 @@ function Update(self)
 						if self.crossTimer:IsPastSimTimeLimit() then
 							local cross = CreateMOSParticle("Particle Heal Effect", "Base.rte");
 							if cross then
-								cross.Pos = healTarget.AboveHUDPos + Vector(0, 4);
+								--Not placed by AboveHUDPos, since that goes by how the HUD was last drawn, which can't be allowed to change the simulation
+								cross.Pos = healTarget.Pos + Vector(0, -healTarget.Height * 0.5 - 2);
 								MovableMan:AddParticle(cross);
 							end
 							healTarget:RemoveWounds(self.healStrength);

Data/Base.rte/Actors/Shared/Scripts/SelfHeal.lua

@@ -22,7 +22,8 @@ function Update(self)
 					end
 				end
 				local cross = self.healCrossParticle:Clone();
-				cross.Pos = self.AboveHUDPos + Vector(0, 4);
+				--Not placed by AboveHUDPos, since that goes by how the HUD was last drawn, which can't be allowed to change the simulation
+				cross.Pos = self.Pos + Vector(0, -self.Height * 0.5 - 2);
 				MovableMan:AddParticle(cross);
 			else
 				local timerRatio = self.healing.timer.ElapsedSimTimeMS/self.healing.delay;

Data/Base.rte/Devices/Special/Medikit/Medikit.lua

@@ -35,7 +35,8 @@ function OnFire(self)
 				MovableMan:AddParticle(part);
 			end
 			local cross = CreateMOSParticle("Particle Heal Effect", "Base.rte");
-			cross.Pos = target.AboveHUDPos + Vector(0, 5);
+			--Not placed by AboveHUDPos, since that goes by how the HUD was last drawn, which can't be allowed to change the simulation
+			cross.Pos = target.Pos + Vector(0, -target.Height * 0.5 - 1);
 			MovableMan:AddParticle(cross);
 
 			if target.Status == Actor.DEAD and target.Health == target.MaxHealth and target.WoundCount == 0 then

Data/Browncoats.rte/Scenes/Objects/Breakables/RefineryDrill/RefineryDrill.lua

@@ -12,14 +12,16 @@ function Create(self)
 
 	self.overloadExplodeSound = CreateSoundContainer("Yskely Refinery Drill Overload Explode", "Browncoats.rte");
 	self.overloadSound = CreateSoundContainer("Yskely Refinery Drill Overload Start", "Browncoats.rte");
+	-- How long the overload sound is, in MS. The drill blows up once that much sim time has gone by, instead of when the audio system is done playing the sound, since that goes by real time.
+	self.overloadSoundLength = 16165;
 
 	self.loopSound = CreateSoundContainer("Yskely Refinery Drill Idle Loop", "Browncoats.rte");
 	self.loopSound:Play(self.Pos + Vector(0, 200));
 end
 
 function ThreadedUpdate(self)
 	if self.overloading then
-		if not self.overloadSound:IsBeingPlayed() and not self.overloadExploded then
+		if self.overloadFXTimer:IsPastSimMS(self.overloadSoundLength) and not self.overloadExploded then
 			self.overloadExplodeSound:Play(self.Pos + Vector(0, 200));
 			self.overloadExploded = true;
 			self.overloadFXTimer:Reset();

Data/Coalition.rte/Devices/Weapons/GatlingGun/GatlingGun.lua

@@ -2,10 +2,12 @@ function Create(self)
 	self.origActivationDelay = self.ActivationDelay;
 	self.spinDownTimer = Timer();
 	self.currentlySpinningDown = false;
+	self.wasActivated = false;
 end
 
 function ThreadedUpdate(self)
-	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.ActiveSound:IsBeingPlayed() then
+	-- The gun starts spinning down when it is let go of after having been activated. It keeps track of that by itself instead of going by whether its ActiveSound is still being played, since that is up to the audio system, which goes by real time.
+	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.wasActivated then
 		self.spinDownTimer:Reset();
 		self.currentlySpinningDown = true;
 		self.activationDelay = self.origActivationDelay;
@@ -16,4 +18,5 @@ function ThreadedUpdate(self)
 		self.ActivationDelay = self.origActivationDelay * self.spinDownTimer.ElapsedSimTimeMS / self.DeactivationDelay;
 		self.currentlySpinningDown = false;
 	end
+	self.wasActivated = self:IsActivated() and not self:IsReloading();
 end

Data/Imperatus.rte/Devices/Weapons/Bulldog/Bulldog.lua

@@ -2,6 +2,7 @@ function Create(self)
 	self.origActivationDelay = self.ActivationDelay;
 	self.spinDownTimer = Timer();
 	self.currentlySpinningDown = false;
+	self.wasActivated = false;
 
 	self.maxRateOfFire = self.RateOfFire;
 	self.minRateOfFire = self.maxRateOfFire * 0.5;
@@ -11,7 +12,8 @@ function Create(self)
 end
 
 function Update(self)
-	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.ActiveSound:IsBeingPlayed() then
+	-- The gun starts spinning down when it is let go of after having been activated. It keeps track of that by itself instead of going by whether its ActiveSound is still being played, since that is up to the audio system, which goes by real time.
+	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.wasActivated then
 		self.spinDownTimer:Reset();
 		self.currentlySpinningDown = true;
 		self.activationDelay = self.origActivationDelay;
@@ -22,6 +24,7 @@ function Update(self)
 		self.ActivationDelay = self.origActivationDelay * self.spinDownTimer.ElapsedSimTimeMS / self.DeactivationDelay;
 		self.currentlySpinningDown = false;
 	end
+	self.wasActivated = self:IsActivated() and not self:IsReloading();
 
 	if self.FiredFrame then
 		self.RateOfFire = math.min(self.RateOfFire * self.increasePerShot, self.maxRateOfFire);

Data/Ronin.rte/Devices/Tools/MedicalDartGun/MedicalDart.lua

@@ -59,7 +59,8 @@ function OnAttach(self, parent)
 		parent = parent:GetRootParent();
 		if IsActor(parent) and MovableMan:IsActor(parent) then
 			local cross = CreateMOSParticle("Particle Heal Effect", "Base.rte");
-			cross.Pos = ToActor(parent).AboveHUDPos + Vector(0, 4);
+			--Not placed by AboveHUDPos, since that goes by how the HUD was last drawn, which can't be allowed to change the simulation
+			cross.Pos = parent.Pos + Vector(0, -ToActor(parent).Height * 0.5 - 2);
 			MovableMan:AddParticle(cross);
 		end
 	end

Data/Techion.rte/Devices/Tools/Nanolyzer/Nanolyzer.lua

@@ -25,6 +25,8 @@ function Create(self)
 
 	--Sounds
 	self.dissipateSound = CreateSoundContainer("Dissipate Sound", "Techion.rte");
+	--The pitch is varied by the sound itself instead of rolled when it gets played. That only happens when it isn't already playing, which is up to the audio system, and that can't be what decides how many of the simulation's random numbers get used
+	self.dissipateSound.PitchVariation = 0.3;
 	self.disintegrationSound = CreateSoundContainer("Disintegration Sound", "Techion.rte");
 end
 
@@ -78,8 +80,7 @@ function OnFire(self)
 					end
 				end
 				if gooCount > 0 then
-					if self.dissipateSound:IsBeingPlayed() then
-						self.dissipateSound.Pitch = RangeRand(RangeRand(0.7, 1.3));
+					if not self.dissipateSound:IsBeingPlayed() then
 						self.dissipateSound:Play(targetMO.Pos);
 					end
 					for i = 1, gooCount do
@@ -166,8 +167,7 @@ function OnFire(self)
 					glow.Pos = hitPos;
 					MovableMan:AddParticle(glow);
 
-					if self.dissipateSound:IsBeingPlayed() then
-						self.dissipateSound.Pitch = RangeRand(RangeRand(0.7, 1.3));
+					if not self.dissipateSound:IsBeingPlayed() then
 						self.dissipateSound:Play(hitPos);
 					end
 				end

Data/Techion.rte/Devices/Weapons/GigaPulsar/GigaPulsar.lua

@@ -2,13 +2,15 @@ function Create(self)
 	self.origActivationDelay = self.ActivationDelay;
 	self.spinDownTimer = Timer();
 	self.currentlySpinningDown = false;
+	self.wasActivated = false;
 
 	self.dingSound = false;
 	self.ejectEffect = CreateAEmitter("Techion Giga Pulsar Magazine Eject Effect", "Techion.rte");
 end
 
 function Update(self)
-	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.ActiveSound:IsBeingPlayed() then
+	-- The gun starts spinning down when it is let go of after having been activated. It keeps track of that by itself instead of going by whether its ActiveSound is still being played, since that is up to the audio system, which goes by real time.
+	if not self.currentlySpinningDown and not self:IsActivated() and not self:IsReloading() and self.wasActivated then
 		self.spinDownTimer:Reset();
 		self.currentlySpinningDown = true;
 		self.activationDelay = self.origActivationDelay;
@@ -19,6 +21,7 @@ function Update(self)
 		self.ActivationDelay = self.origActivationDelay * self.spinDownTimer.ElapsedSimTimeMS / self.DeactivationDelay;
 		self.currentlySpinningDown = false;
 	end
+	self.wasActivated = self:IsActivated() and not self:IsReloading();
 
 	if self.Magazine then
 		self.lastMag = self.Magazine;

Data/Uzira.rte/Devices/Special/Gunsword/Gunsword.lua

@@ -7,6 +7,9 @@ function Create(self)
 	self.charge = 0;
 	self.throwSpeed = 0;
 	self.swingSound = CreateSoundContainer("Uzira.rte/Swing");
+	--How long the swing sounds are, in MS. The next swing waits for that much sim time, instead of for the audio system to be done playing the sound, since that goes by real time
+	self.swingSoundLength = 500;
+	self.swingSoundTimer = Timer();
 
 	self.particle = CreateMOPixel("Base.rte/Smack Particle");
 	self.particle.IgnoresTeamHits = true;
@@ -58,7 +61,8 @@ function Update(self)
 						end
 
 						parent.Vel = parent.Vel + Vector(swingSpeed/(5 + self.momentum), 0):RadRotate(parent:GetAimAngle(true));
-						if not self.swingSound:IsBeingPlayed() then
+						if self.swingSoundTimer:IsPastSimMS(self.swingSoundLength/self.swingSound.Pitch) then
+							self.swingSoundTimer:Reset();
 							self.swingSound.Pos = self.Pos;
 							self.swingSound:Play();
 							self:RemoveWounds(1);

RTEA.vcxproj

@@ -826,6 +826,7 @@
     <ClInclude Include="Source\System\Reader.h" />
     <ClInclude Include="Source\System\Serializable.h" />
     <ClInclude Include="Source\System\Singleton.h" />
+    <ClInclude Include="Source\System\DeterminismChecker.h" />
     <ClInclude Include="Source\System\System.h" />
     <ClInclude Include="Source\System\Timer.h" />
     <ClInclude Include="Source\System\Vector.h" />
@@ -1362,6 +1363,7 @@
     </ClCompile>
     <ClCompile Include="Source\System\PathFinder.cpp" />
     <ClCompile Include="Source\System\Reader.cpp" />
+    <ClCompile Include="Source\System\DeterminismChecker.cpp" />
     <ClCompile Include="Source\System\System.cpp" />
     <ClCompile Include="Source\System\Timer.cpp" />
     <ClCompile Include="Source\System\Vector.cpp" />

RTEA.vcxproj.filters

@@ -88,6 +88,9 @@
     <ClInclude Include="Source\System\Singleton.h">
       <Filter>System</Filter>
     </ClInclude>
+    <ClInclude Include="Source\System\DeterminismChecker.h">
+      <Filter>System</Filter>
+    </ClInclude>
     <ClInclude Include="Source\System\System.h">
       <Filter>System</Filter>
     </ClInclude>
@@ -685,6 +688,9 @@
     <ClCompile Include="Source\System\Reader.cpp">
       <Filter>System</Filter>
     </ClCompile>
+    <ClCompile Include="Source\System\DeterminismChecker.cpp">
+      <Filter>System</Filter>
+    </ClCompile>
     <ClCompile Include="Source\System\System.cpp">
       <Filter>System</Filter>
     </ClCompile>

Source/Entities/ACraft.cpp

@@ -807,9 +807,10 @@ void ACraft::DrawHUD(BITMAP* pTargetBitmap, const Vector& targetPos, int whichSc
 				continue;
 			}
 
-			Vector exitRadius = RotateOffset(exit->GetVelocity().GetPerpendicular().SetMagnitude(exit->GetRadius()));
+			// These are without the spread, which gets rolled with the simulation's random numbers. Drawing can't be allowed to use those up.
+			Vector exitRadius = RotateOffset(exit->GetBaseVelocity().GetPerpendicular().SetMagnitude(exit->GetRadius()));
 			Vector exitCorner = m_Pos - targetPos + RotateOffset(exit->GetOffset()) + exitRadius;
-			Vector arrowVec = RotateOffset(exit->GetVelocity().SetMagnitude(exit->GetRange()));
+			Vector arrowVec = RotateOffset(exit->GetBaseVelocity().SetMagnitude(exit->GetRange()));
 			g_FrameMan.DrawLine(pTargetBitmap, exitCorner, exitCorner + arrowVec, 120, 120, EXITLINESPACING, m_ExitLinePhase);
 			exitCorner -= exitRadius * 2;
 			g_FrameMan.DrawLine(pTargetBitmap, exitCorner, exitCorner + arrowVec, 120, 120, EXITLINESPACING, m_ExitLinePhase);

Source/Entities/ACraft.h

@@ -71,10 +71,14 @@ namespace RTE {
 			/// @return The coordinates relative to the m_Pos of this' ACraft.
 			Vector GetOffset() const { return m_Offset; }
 
-			/// Gets the velocity of anything that exits through this.
+			/// Gets the velocity of anything that exits through this. Its spread is rolled anew every time, with the simulation's random numbers.
 			/// @return The velocity vector for anything exiting through this.
 			Vector GetVelocity() const { return m_Velocity * (1.0F + m_VelSpread * RandomNormalNum()); }
 
+			/// Gets the velocity of anything that exits through this as it is before any spread, which is also the way that this faces.
+			/// @return The velocity vector of this, with no spread to it.
+			Vector GetBaseVelocity() const { return m_Velocity; }
+
 			/// Gets the width from the center tanget created by the velocity vector
 			/// out from the offet point. This times two gives the total width of the
 			/// opening.