using System; using System.Collections.Generic; using System.Linq; using System.Reflection; using CultMath; using Xunit; using static CultMath.math; using float3 = CultMath.float3; using int2 = CultMath.int2; // Cut sim-rate (ruling lower-game-sim-rate, map docs/aetheria-arena-sim-rate-map.md): the game's tick has one owner, // and content authored in seconds means the same at every tick, because a restarted timer keeps what the last step // overshot and passive sensing decays exactly. public sealed class SimRateClockTests { [Fact] public void OneTickOwner() { var clock = SimClock.ForGame(); Assert.Equal(1f / SimClock.TickRate, SimClock.GameStep); Assert.Equal(SimClock.GameStep, clock.Step); Assert.Equal(SimClock.TickRate, clock.StepsPerRealSecond); // Ten real seconds of irregular frames pay ten seconds of steps, so the game runs at real time. var frames = new[] { .004f, .031f, .016f, .0083f, .05f, .022f, .0125f, .027f }; var real = 0f; for (var i = 0; real < 10f; i++) { var frame = Math.Min(frames[i % frames.Length], 10f - real); real += frame; clock.Advance(frame, _ => { }); } Assert.InRange(clock.Steps, 10 * SimClock.TickRate - 1, 10 * SimClock.TickRate + 1); } } public sealed partial class ContactRevealTests { private static readonly float[] CadenceSteps = { 1f / 60f, 1f / 30f, 1f / 20f, 1f / 15f }; private static readonly float[] Cooldowns = { .25f, .13f }; // A gun of its own cooldown, bottomless magazine, so only the cooldown paces it. Upserted by name into the open catalog. private string GunWithCooldown(float cooldown) { var name = $"Gun@{cooldown:R}"; if (_openCache.GetByName(name) != null) return name; var gun = Armed(new InstantWeaponData { Count = Const(1), BurstTime = Const(0), Cooldown = Const(cooldown) }, 0); gun.Energy = Const(1); // the fixture reactor pays a round a hundredth of a second apart; the rounds-per-step tests top up nothing _openCache.Upsert(new WeaponItemData { Name = name, Hardpoint = HardpointType.Sensors, Shape = new Shape(), Durability = 1, MinimumTemperature = -1000, MaximumTemperature = 1000, OptimalTemperature = 0, PlateauWidth = 2000, Fuse = WeaponFuse.Proximity, BlastRadius = 30f, Behaviors = { gun } }); return name; } // Holds the trigger for `seconds`, topping up the capacitor so only the cooldown paces the gun. Returns the zone // time of each round. private List HoldTrigger(Ship ship, EquippedItem item, float dt, float seconds, List fireTimes = null) { var gun = (InstantWeapon) item.Behaviors.Single(b => b is InstantWeapon); var capacitor = (InputCapacitor) typeof(InstantWeapon).GetField("_capacitor", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(gun); var rounds = new List(); gun.OnFire += id => { rounds.Add(_zone.Time); if (fireTimes != null && _zone.TryGetShot(id, out var shot)) fireTimes.Add(shot.FireTime); }; ship.SetTarget(TargetRef.None); for (var step = 0; step < (int) MathF.Round(seconds / dt); step++) { capacitor.AddStepCharge(1000f, dt); gun.Activate(); Tick(dt); } return rounds; } [Fact] public void CooldownCadenceIsPerSecond() { foreach (var cooldown in Cooldowns) foreach (var dt in CadenceSteps) { var ship = Add(float3(0, 0, 0), new[] { GunWithCooldown(cooldown) }, new[] { "Targeting", "Reactor" }); var rounds = HoldTrigger(ship, Guns(ship)[0], dt, 30f); var expected = 30f / cooldown; Assert.True(abs(rounds.Count - expected) <= 1.01f, $"cooldown {cooldown} at dt {dt}: {rounds.Count} rounds, expected {expected} +-1"); } } [Fact] public void CooldownNeverFastFires() { foreach (var cooldown in Cooldowns) foreach (var dt in CadenceSteps) { var ship = Add(float3(0, 0, 0), new[] { GunWithCooldown(cooldown) }, new[] { "Targeting", "Reactor" }); var item = Guns(ship)[0]; for (var i = 0; i < 20; i++) Tick(dt); // idle: the finished timer banks at most one step var rounds = HoldTrigger(ship, item, dt, 10f); Assert.True(rounds.Count > 3); for (var i = 1; i < rounds.Count; i++) Assert.True(rounds[i] - rounds[i - 1] >= cooldown - dt - 1e-4f, $"cooldown {cooldown} at dt {dt}: rounds {rounds[i - 1]} and {rounds[i]}"); } } private int PingsHeld(float pingCooldown, float dt, float seconds) { var name = $"Pinger@{pingCooldown:R}"; if (_openCache.GetByName(name) == null) { var sensor = SensorBehavior(sensitivity: 2f); sensor.PingCooldown = Const(pingCooldown); _openCache.Upsert(new GearData { Name = name, Hardpoint = HardpointType.Sensors, Shape = new Shape(), Durability = 1, MinimumTemperature = -1000, MaximumTemperature = 1000, OptimalTemperature = 0, PlateauWidth = 2000, Behaviors = { sensor } }); } var ship = Add(float3(0, 0, 0), new[] { name }); var pings = 0; SensorOf(ship).OnPingStart += () => pings++; for (var step = 0; step < (int) MathF.Round(seconds / dt); step++) { SensorOf(ship).Ping(); Tick(dt); } return pings; } [Fact] public void PingCooldownCarriesItsOvershoot() { foreach (var cooldown in new[] { .5f, .26f }) foreach (var dt in CadenceSteps) { var pings = PingsHeld(cooldown, dt, 30f); Assert.True(abs(pings - 30f / cooldown) <= 1.01f, $"ping cooldown {cooldown} at dt {dt}: {pings} pings, expected {30f / cooldown} +-1"); } } [Fact] public void CooldownBehaviourCarriesItsOvershoot() { foreach (var cooldown in new[] { .5f, .26f }) foreach (var dt in CadenceSteps) { var name = $"Metronome@{cooldown:R}"; if (_openCache.GetByName(name) == null) _openCache.Upsert(Tool(name, new CooldownData { Cooldown = Const(cooldown) })); var ship = Add(float3(0, 0, 0), null, new[] { name }); var clock = ship.Equipment.SelectMany(i => i.Behaviors).OfType().Single(); var fired = 0; for (var step = 0; step < (int) MathF.Round(30f / dt); step++) { Tick(dt); if (clock.Execute(dt)) fired++; } Assert.True(abs(fired - 30f / cooldown) <= 1.01f, $"cooldown {cooldown} at dt {dt}: {fired} restarts, expected {30f / cooldown} +-1"); } } [Fact] public void AmmoIntervalCarriesItsOvershoot() { _openCache.Upsert(new SimpleCommodityData { Name = "Slug", Shape = new Shape(), Price = 1, MaxStack = 100 }); foreach (var interval in new[] { .5f, .26f }) foreach (var dt in CadenceSteps) { var name = $"Stream@{interval:R}"; if (_openCache.GetByName(name) == null) { var beam = (ConstantWeaponData) Armed(new ConstantWeaponData(), 100000); beam.AmmoInterval = interval; beam.AmmoType = _openCache.RefOf(_openCache.GetByName("Slug")); _openCache.Upsert(new WeaponItemData { Name = name, Hardpoint = HardpointType.Sensors, Shape = new Shape(), Durability = 1, MinimumTemperature = -1000, MaximumTemperature = 1000, OptimalTemperature = 0, PlateauWidth = 2000, Fuse = WeaponFuse.Proximity, BlastRadius = 30f, Behaviors = { beam } }); } var ship = Add(float3(0, 0, 0), new[] { name }, new[] { "Targeting", "Reactor" }); var weapon = ship.Equipment.SelectMany(i => i.Behaviors).OfType().Single(); typeof(ConstantWeapon).GetField("_ammo", BindingFlags.Instance | BindingFlags.NonPublic).SetValue(weapon, 100000); ship.SetTarget(TargetRef.None); weapon.Activate(); for (var step = 0; step < (int) MathF.Round(30f / dt); step++) Tick(dt); var spent = 100000 - weapon.Ammo; Assert.True(abs(spent - 30f / interval) <= 1.01f, $"ammo interval {interval} at dt {dt}: {spent} spent, expected {30f / interval} +-1"); } } // A fixed target under passive sensing settles where Entity.PassiveInfo says (G / k), at any step. [Fact] public void PassiveInfoSettlesAtTheDocumentedLevel() { foreach (var dt in new[] { 1f / 60f, 1f / 15f }) { var observer = Add(float3(0, 0, 0), new[] { "Eye" }); var target = Add(float3(0, 0, 100)); var marker = new object(); void Glow() => target.SetSignature(marker, SignatureChannel.Thermal, 5f, null); // held as bright as a thruster Glow(); Tick(0f); var distance = 100f; while (observer.PassiveInfo(float2(0, distance), target.Visibility) > .5f) { distance *= 2; target.Position = float3(0, 0, distance); } var documented = observer.PassiveInfo(target.Position.xz, target.Visibility); Assert.InRange(documented, 1e-4f, .5f); for (var step = 0; step < (int) MathF.Round(40f / dt); step++) { Glow(); Tick(dt); } Assert.InRange(Track(observer, target), documented - 1e-3f, documented + 1e-3f); } } // An idle timer banks at most one step: after ten idle seconds the first two restarts are still a cooldown apart. [Fact] public void AnIdleSensorBanksAtMostOneStep() { foreach (var dt in CadenceSteps) { var name = "Pinger@.5"; if (_openCache.GetByName(name) == null) { var sensor = SensorBehavior(sensitivity: 2f); sensor.PingCooldown = Const(.5f); _openCache.Upsert(new GearData { Name = name, Hardpoint = HardpointType.Sensors, Shape = new Shape(), Durability = 1, MinimumTemperature = -1000, MaximumTemperature = 1000, OptimalTemperature = 0, PlateauWidth = 2000, Behaviors = { sensor } }); } var ship = Add(float3(0, 0, 0), new[] { name }); var times = new List(); SensorOf(ship).OnPingStart += () => times.Add(_zone.Time); for (var step = 0; step < (int) MathF.Round(10f / dt); step++) Tick(dt); for (var step = 0; step < (int) MathF.Round(3f / dt); step++) { SensorOf(ship).Ping(); Tick(dt); } Assert.True(times.Count >= 4); for (var i = 1; i < times.Count; i++) Assert.True(times[i] - times[i - 1] >= .5f - dt - 1e-4f, $"dt {dt}: pings at {times[i - 1]} and {times[i]}"); } } [Fact] public void AnIdleCooldownBanksAtMostOneStep() { foreach (var dt in CadenceSteps) { var name = "Metronome@.5"; if (_openCache.GetByName(name) == null) _openCache.Upsert(Tool(name, new CooldownData { Cooldown = Const(.5f) })); var ship = Add(float3(0, 0, 0), null, new[] { name }); var clock = ship.Equipment.SelectMany(i => i.Behaviors).OfType().Single(); for (var step = 0; step < (int) MathF.Round(10f / dt); step++) Tick(dt); var times = new List(); for (var step = 0; step < (int) MathF.Round(3f / dt); step++) { Tick(dt); if (clock.Execute(dt)) times.Add(_zone.Time); } Assert.True(times.Count >= 4); for (var i = 1; i < times.Count; i++) Assert.True(times[i] - times[i - 1] >= .5f - dt - 1e-4f, $"dt {dt}: restarts at {times[i - 1]} and {times[i]}"); } } // A magazine of three, cooldown .1 s and a .9 s reload is three rounds a 1.1 s cycle, at any step. // Ruling rounds-per-step: cadence is authored in seconds at any tick rate. A gun of 0.01 s fires 100 rounds a second at 15, 30 // and 60 Hz (several in one step), each born at its own moment inside the step, one cooldown after the one before. [Fact] public void AFastGunDeliversItsAuthoredRoundsAtEveryRate() { foreach (var dt in new[] { 1f / 60f, 1f / 30f, 1f / 15f }) { var ship = Add(float3(0, 0, 0), new[] { GunWithCooldown(.01f) }, new[] { "Targeting", "Reactor" }); var fireTimes = new List(); var rounds = HoldTrigger(ship, Guns(ship)[0], dt, 10f, fireTimes); var probe = (InstantWeapon) Guns(ship)[0].Behaviors.Single(b => b is InstantWeapon); var cap = (InputCapacitor) typeof(InstantWeapon).GetField("_capacitor", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(probe); Assert.True(abs(rounds.Count - 1000f) <= 1.01f, $"dt {dt}: {rounds.Count} rounds in 10 s, expected 1000 +-1; capacity {cap.Capacity} rate {cap.Rate} charge {cap.Charge} cooldown {probe.Cooldown} canfire {probe.CanFire} firing {probe.Firing}"); Assert.Equal(rounds.Count, fireTimes.Count); for (var i = 1; i < fireTimes.Count; i++) Assert.True(abs(fireTimes[i] - fireTimes[i - 1] - .01f) < 2e-4f, $"dt {dt}: rounds {i - 1} and {i} born {fireTimes[i - 1]:R} and {fireTimes[i]:R}"); } } // Rounds born in one step leave from where the shooter was at their own moment: the origins of two rounds of a step are // apart by the shooter's velocity times the time between them. [Fact] public void RoundsOfOneStepLeaveFromWhereTheShooterWasAtTheirMoment() { var dt = 1f / 15f; var ship = Add(float3(0, 0, 0), new[] { GunWithCooldown(.01f) }, new[] { "Targeting", "Reactor" }); ship.Velocity = float2(30, 0); var gun = (InstantWeapon) Guns(ship)[0].Behaviors.Single(b => b is InstantWeapon); var born = new List<(float step, float time, float x, float velocity)>(); gun.OnFire += id => { if (_zone.TryGetShot(id, out var shot)) born.Add((_zone.Time, shot.FireTime, shot.FireOrigin.x, ship.Velocity.x)); }; ship.SetTarget(TargetRef.None); for (var i = 0; i < 20; i++) { gun.Activate(); Tick(dt); } var pairs = 0; for (var i = 1; i < born.Count; i++) { if (born[i].step != born[i - 1].step) continue; pairs++; var expected = born[i].velocity * (born[i].time - born[i - 1].time); Assert.True(abs(born[i].x - born[i - 1].x - expected) < 1e-2f, $"round {i}: origins {born[i - 1].x} and {born[i].x}, expected {expected} apart"); } Assert.True(pairs > 100, $"{pairs} pairs of rounds in one step"); } // A cooldown of nothing is a gun as fast as the shortest cycle, not a step that never ends. [Fact] public void AGunWithNoCooldownFiresAtTheShortestCycle() { var ship = Add(float3(0, 0, 0), new[] { GunWithCooldown(0f) }, new[] { "Targeting", "Reactor" }); var rounds = HoldTrigger(ship, Guns(ship)[0], 1f / 30f, 1f); Assert.True(abs(rounds.Count - 2000f) <= 1.01f, $"{rounds.Count} rounds in 1 s, expected 2000 +-1"); } // The cluster's cost: a point-defence battery of 0.005 s guns holding its trigger, every round a queued shot with its own // roll. The step wall time and the heap bytes per round are written beside the test for the report. [Fact, Trait("Category", "Slow")] public void ADenseClusterStepsAtAffordableCost() { const int guns = 16; var dt = SimClock.GameStep; var ships = Enumerable.Range(0, guns).Select(i => Add(float3(i * 3, 0, 0), new[] { GunWithCooldown(.005f) }, new[] { "Targeting", "Reactor" })).ToList(); var weapons = ships.Select(s => (InstantWeapon) Guns(s)[0].Behaviors.Single(b => b is InstantWeapon)).ToList(); var capacitors = weapons.Select(w => (InputCapacitor) typeof(InstantWeapon).GetField("_capacitor", BindingFlags.Instance | BindingFlags.NonPublic).GetValue(w)).ToList(); var rounds = 0; foreach (var w in weapons) w.OnFire += _ => rounds++; foreach (var s in ships) s.SetTarget(TargetRef.None); void Step() { for (var i = 0; i < guns; i++) { capacitors[i].AddStepCharge(1000f, dt); weapons[i].Activate(); } Tick(dt); } for (var i = 0; i < 30; i++) Step(); // warm the JIT and the shot queue for (var i = 0; i < 60; i++) Tick(dt); // let the in-flight rounds resolve var steps = 300; var idleBytes = GC.GetAllocatedBytesForCurrentThread(); var idle = System.Diagnostics.Stopwatch.StartNew(); for (var i = 0; i < steps; i++) Tick(dt); idle.Stop(); idleBytes = GC.GetAllocatedBytesForCurrentThread() - idleBytes; rounds = 0; var bytes = GC.GetAllocatedBytesForCurrentThread(); var watch = System.Diagnostics.Stopwatch.StartNew(); for (var i = 0; i < steps; i++) Step(); watch.Stop(); bytes = GC.GetAllocatedBytesForCurrentThread() - bytes; // Where the bytes go: a round's birth (FireControl.Fire) alone, and the queued rounds' commit and resolution alone. var item0 = Guns(ships[0])[0]; for (var i = 0; i < 2000; i++) FireControl.Fire(weapons[0], item0, ships[0]); // grows the shot queue once Tick(dt); var born = GC.GetAllocatedBytesForCurrentThread(); for (var i = 0; i < 1000; i++) FireControl.Fire(weapons[0], item0, ships[0]); born = GC.GetAllocatedBytesForCurrentThread() - born; var settle = GC.GetAllocatedBytesForCurrentThread(); Tick(dt); settle = GC.GetAllocatedBytesForCurrentThread() - settle; var line = $"born {born / 1000.0:F0} B per round, 1050 rounds resolved in one step {settle / 1050.0:F0} B per round; {guns} guns at .005 s, {SimClock.TickRate} Hz: {rounds / (double) steps:F1} rounds per step, {watch.Elapsed.TotalMilliseconds / steps:F3} ms per step, {(bytes - idleBytes) / (double) rounds:F0} heap bytes per round beyond the idle step (idle step {idle.Elapsed.TotalMilliseconds / steps:F3} ms, {idleBytes / (double) steps:F0} bytes)"; System.IO.File.WriteAllText(System.IO.Path.Combine(System.IO.Path.GetTempPath(), "simrate-stepcost.txt"), line); Assert.True(Math.Abs(rounds / (double) steps - guns * dt / .005) < 1.0 * guns, line); } [Fact] public void MagazineCadenceIsPerSecond() { foreach (var dt in CadenceSteps) { var name = "Magazine3"; if (_openCache.GetByName(name) == null) { var gun = Armed(new InstantWeaponData { Count = Const(1), BurstTime = Const(0), Cooldown = Const(.1f), ReloadTime = .9f }, 3); _openCache.Upsert(new WeaponItemData { Name = name, Hardpoint = HardpointType.Sensors, Shape = new Shape(), Durability = 1, MinimumTemperature = -1000, MaximumTemperature = 1000, OptimalTemperature = 0, PlateauWidth = 2000, Fuse = WeaponFuse.Proximity, BlastRadius = 30f, Behaviors = { gun } }); } var ship = Add(float3(0, 0, 0), new[] { name }, new[] { "Targeting", "Reactor" }); var rounds = HoldTrigger(ship, Guns(ship)[0], dt, 33f); Assert.True(abs(rounds.Count - 90f) <= 3.01f, $"dt {dt}: {rounds.Count} rounds in 33 s, expected 90 +-3"); } } } public sealed partial class RunStartTests { private static readonly string EquivalenceTable = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "simrate-equivalence.txt"); // The two-AI fight over 40 match seeds at the old 60 Hz and at the game's step: the same fight to within noise. The // win rate (east's hull above west's) differs by less than a 95% two-proportion interval, and the mean survivor hull // and the mean time to first kill each differ by less than their 95% interval. The table is written beside the test for the report. [Fact, Trait("Category", "Slow")] public void SimRateEquivalence() { const int seeds = 40; var table = new System.Text.StringBuilder(); (double wins, double survivor, double firstKill, double seconds, double survivorVar, double firstKillVar) Run(float dt) { var wins = 0; double survivor = 0, firstKill = 0, seconds = 0; var survivors = new List(); var kills = new List(); for (uint seed = 1; seed <= seeds; seed++) { var fight = TwoAiFight(seed, dt); if (fight.eastHull > fight.westHull) wins++; survivor += Math.Max(fight.eastHull, fight.westHull); survivors.Add(Math.Max(fight.eastHull, fight.westHull)); kills.Add(fight.firstKill); firstKill += fight.firstKill; seconds += fight.stepSeconds; table.AppendLine($"dt {dt:R} seed {seed}: east {fight.eastHull:R} west {fight.westHull:R} first kill {fight.firstKill:R} s, {fight.stepSeconds:F2} s wall"); } double Variance(List xs) { var m = xs.Average(); return xs.Sum(x => (x - m) * (x - m)) / (xs.Count - 1); } return (wins / (double) seeds, survivor / seeds, firstKill / seeds, seconds, Variance(survivors), Variance(kills)); } var old = Run(1f / 60f); var now = Run(SimClock.GameStep); var se = Math.Sqrt(old.wins * (1 - old.wins) / seeds + now.wins * (1 - now.wins) / seeds); table.AppendLine($"60 Hz: east wins {old.wins:P0}, mean survivor hull {old.survivor:F1}, mean first kill {old.firstKill:F2} s, {old.seconds:F1} s wall"); table.AppendLine($"{SimClock.TickRate} Hz: east wins {now.wins:P0}, mean survivor hull {now.survivor:F1}, mean first kill {now.firstKill:F2} s, {now.seconds:F1} s wall"); table.AppendLine($"win-rate difference {Math.Abs(old.wins - now.wins):F3} (95% interval +-{1.96 * se:F3}); wall-time speedup {old.seconds / now.seconds:F2}x"); System.IO.File.WriteAllText(EquivalenceTable, table.ToString()); Assert.True(Math.Abs(old.wins - now.wins) <= 1.96 * se, table.ToString()); // The survivor hull is heavy-tailed (a dead hull reads near zero, a survivor up to a few hundred), so its tolerance is the // 95% interval of the difference of the two means, as the win rate's is, not a fixed fraction of one mean. var survivorSe = Math.Sqrt(old.survivorVar / seeds + now.survivorVar / seeds); var killSe = Math.Sqrt(old.firstKillVar / seeds + now.firstKillVar / seeds); table.AppendLine($"mean survivor hull difference {Math.Abs(now.survivor - old.survivor):F2} (95% interval +-{1.96 * survivorSe:F2}); mean first kill difference {Math.Abs(now.firstKill - old.firstKill):F2} s (95% interval +-{1.96 * killSe:F2})"); System.IO.File.WriteAllText(EquivalenceTable, table.ToString()); Assert.True(Math.Abs(now.survivor - old.survivor) <= 1.96 * survivorSe, table.ToString()); Assert.True(Math.Abs(now.firstKill - old.firstKill) <= 1.96 * killSe, table.ToString()); } }