Revert "Revert "epic Respiration Rework"" (#6527)

Content.IntegrationTests/Tests/Body/LungTest.cs

@@ -1,7 +1,7 @@
-using System;
+using System.Threading.Tasks;
-using System.Linq;
-using System.Threading.Tasks;
 using Content.Server.Atmos;
+using Content.Server.Atmos.Components;
+using Content.Server.Atmos.EntitySystems;
 using Content.Server.Body.Components;
 using Content.Server.Body.Systems;
 using Content.Shared.Atmos;
@@ -9,7 +9,6 @@ using Content.Shared.Body.Components;
 using NUnit.Framework;
 using Robust.Server.Maps;
 using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
 using Robust.Shared.Map;
 using Robust.Shared.Maths;
 
@@ -21,16 +20,17 @@ namespace Content.IntegrationTests.Tests.Body
     {
         private const string Prototypes = @"
 - type: entity
-  name: HumanBodyAndBloodstreamDummy
+  name: HumanBodyDummy
-  id: HumanBodyAndBloodstreamDummy
+  id: HumanBodyDummy
   components:
-  - type: Bloodstream
-    max_volume: 100
   - type: SolutionContainerManager
   - type: Body
     template: HumanoidTemplate
     preset: HumanPreset
     centerSlot: torso
+  - type: MobState
+    thresholds:
+      0: !type:NormalMobState {}
   - type: ThermalRegulator
     metabolismHeat: 5000
     radiatedHeat: 400
@@ -40,101 +40,84 @@ namespace Content.IntegrationTests.Tests.Body
     normalBodyTemperature: 310.15
     thermalRegulationTemperatureThreshold: 25
   - type: Respirator
-    needsGases:
-      Oxygen: 0.00060763888
-    producesGases:
-      Oxygen: 0.00045572916
-      CarbonDioxide: 0.00015190972
 ";
 
         [Test]
         public async Task AirConsistencyTest()
         {
+            // --- Setup
             var options = new ServerContentIntegrationOption{ExtraPrototypes = Prototypes};
             var server = StartServer(options);
 
-            server.Assert(() =>
+            await server.WaitIdleAsync();
+
+            var mapLoader = server.ResolveDependency<IMapLoader>();
+            var mapManager = server.ResolveDependency<IMapManager>();
+            var entityManager = server.ResolveDependency<IEntityManager>();
+            RespiratorSystem respSys = default;
+            MetabolizerSystem metaSys = default;
+
+            MapId mapId;
+            IMapGrid grid = null;
+            SharedBodyComponent body = default;
+            EntityUid human = default;
+            GridAtmosphereComponent relevantAtmos = default;
+            float startingMoles = 0.0f;
+
+            var testMapName = "Maps/Test/Breathing/3by3-20oxy-80nit.yml";
+
+            await server.WaitPost(() =>
             {
-                var mapManager = IoCManager.Resolve<IMapManager>();
+                mapId = mapManager.CreateMap();
-
+                grid = mapLoader.LoadBlueprint(mapId, testMapName);
-                var mapId = mapManager.CreateMap();
-
-                var entityManager = IoCManager.Resolve<IEntityManager>();
-
-                var human = entityManager.SpawnEntity("HumanBodyAndBloodstreamDummy", new MapCoordinates(Vector2.Zero, mapId));
-
-                var bodySys = EntitySystem.Get<BodySystem>();
-                var lungSys = EntitySystem.Get<LungSystem>();
-
-                Assert.That(entityManager.TryGetComponent(human, out SharedBodyComponent body));
-
-                var lungs = bodySys.GetComponentsOnMechanisms<LungComponent>(human, body).ToArray();
-                Assert.That(lungs.Count, Is.EqualTo(1));
-                Assert.That(entityManager.TryGetComponent(human, out BloodstreamComponent bloodstream));
-
-                var gas = new GasMixture(1);
-
-                var originalOxygen = 2;
-                var originalNitrogen = 8;
-                var breathedPercentage = Atmospherics.BreathVolume / gas.Volume;
-
-                gas.AdjustMoles(Gas.Oxygen, originalOxygen);
-                gas.AdjustMoles(Gas.Nitrogen, originalNitrogen);
-
-                var (lung, _) = lungs[0];
-                lungSys.TakeGasFrom(((IComponent) lung).Owner, 1, gas, lung);
-
-                var lungOxygen = originalOxygen * breathedPercentage;
-                var lungNitrogen = originalNitrogen * breathedPercentage;
-
-                Assert.That(bloodstream.Air.GetMoles(Gas.Oxygen), Is.EqualTo(lungOxygen));
-                Assert.That(bloodstream.Air.GetMoles(Gas.Nitrogen), Is.EqualTo(lungNitrogen));
-
-                var mixtureOxygen = originalOxygen - lungOxygen;
-                var mixtureNitrogen = originalNitrogen - lungNitrogen;
-
-                Assert.That(gas.GetMoles(Gas.Oxygen), Is.EqualTo(mixtureOxygen));
-                Assert.That(gas.GetMoles(Gas.Nitrogen), Is.EqualTo(mixtureNitrogen));
-
-                var lungOxygenBeforeExhale = lung.Air.GetMoles(Gas.Oxygen);
-                var lungNitrogenBeforeExhale = lung.Air.GetMoles(Gas.Nitrogen);
-
-                // Empty after it transfer to the bloodstream
-                Assert.Zero(lungOxygenBeforeExhale);
-                Assert.Zero(lungNitrogenBeforeExhale);
-
-                lungSys.PushGasTo(((IComponent) lung).Owner, gas, lung);
-
-                var lungOxygenAfterExhale = lung.Air.GetMoles(Gas.Oxygen);
-                var exhaledOxygen = Math.Abs(lungOxygenBeforeExhale - lungOxygenAfterExhale);
-
-                // Not completely empty
-                Assert.Positive(lung.Air.Moles.Sum());
-
-                // Retains needed gas
-                Assert.Positive(bloodstream.Air.GetMoles(Gas.Oxygen));
-
-                // Expels toxins
-                Assert.Zero(bloodstream.Air.GetMoles(Gas.Nitrogen));
-
-                mixtureOxygen += exhaledOxygen;
-
-                var finalTotalOxygen = gas.GetMoles(Gas.Oxygen) +
-                                         bloodstream.Air.GetMoles(Gas.Oxygen) +
-                                         lung.Air.GetMoles(Gas.Oxygen);
-
-                // No ticks were run, metabolism doesn't run and so no oxygen is used up
-                Assert.That(finalTotalOxygen, Is.EqualTo(originalOxygen));
-                Assert.That(gas.GetMoles(Gas.Oxygen), Is.EqualTo(mixtureOxygen).Within(0.000001f));
-
-                var finalTotalNitrogen = gas.GetMoles(Gas.Nitrogen) +
-                                         bloodstream.Air.GetMoles(Gas.Nitrogen) +
-                                         lung.Air.GetMoles(Gas.Nitrogen);
-
-                // Nitrogen stays constant
-                Assert.That(finalTotalNitrogen, Is.EqualTo(originalNitrogen).Within(0.000001f));
             });
 
+            Assert.NotNull(grid, $"Test blueprint {testMapName} not found.");
+
+            float GetMapMoles()
+            {
+                var totalMapMoles = 0.0f;
+                foreach (var tile in relevantAtmos.Tiles.Values)
+                {
+                    totalMapMoles += tile.Air?.TotalMoles ?? 0.0f;
+                }
+
+                return totalMapMoles;
+            }
+
+            await server.WaitAssertion(() =>
+            {
+                var coords = new Vector2(0.5f, -1f);
+                var coordinates = new EntityCoordinates(grid.GridEntityId, coords);
+                human = entityManager.SpawnEntity("HumanBodyDummy", coordinates);
+                respSys = EntitySystem.Get<RespiratorSystem>();
+                metaSys = EntitySystem.Get<MetabolizerSystem>();
+                relevantAtmos = entityManager.GetComponent<GridAtmosphereComponent>(grid.GridEntityId);
+                startingMoles = GetMapMoles();
+
+                Assert.True(entityManager.TryGetComponent(human, out body));
+                Assert.True(entityManager.HasComponent<RespiratorComponent>(human));
+            });
+
+            // --- End setup
+
+            var inhaleCycles = 100;
+            for (var i = 0; i < inhaleCycles; i++)
+            {
+                await server.WaitAssertion(() =>
+                {
+                    // inhale
+                    respSys.Update(2.0f);
+                    Assert.That(GetMapMoles(), Is.LessThan(startingMoles));
+
+                    // metabolize + exhale
+                    metaSys.Update(1.0f);
+                    metaSys.Update(1.0f);
+                    respSys.Update(2.0f);
+                    Assert.That(GetMapMoles(), Is.EqualTo(startingMoles).Within(0.0001));
+                });
+            }
+
             await server.WaitIdleAsync();
         }
 
@@ -169,22 +152,21 @@ namespace Content.IntegrationTests.Tests.Body
             {
                 var center = new Vector2(0.5f, -1.5f);
                 var coordinates = new EntityCoordinates(grid.GridEntityId, center);
-                human = entityManager.SpawnEntity("HumanBodyAndBloodstreamDummy", coordinates);
+                human = entityManager.SpawnEntity("HumanBodyDummy", coordinates);
 
                 Assert.True(entityManager.HasComponent<SharedBodyComponent>(human));
                 Assert.True(entityManager.TryGetComponent(human, out respirator));
-                Assert.False(respirator.Suffocating);
+                Assert.False(respirator.SuffocationCycles > respirator.SuffocationCycleThreshold);
             });
 
             var increment = 10;
 
-
             for (var tick = 0; tick < 600; tick += increment)
             {
                 await server.WaitRunTicks(increment);
                 await server.WaitAssertion(() =>
                 {
-                    Assert.False(respirator.Suffocating, $"Entity {entityManager.GetComponent<MetaDataComponent>(human).EntityName} is suffocating on tick {tick}");
+                    Assert.False(respirator.SuffocationCycles > respirator.SuffocationCycleThreshold, $"Entity {entityManager.GetComponent<MetaDataComponent>(human).EntityName} is suffocating on tick {tick}");
                 });
             }
 

Content.Server/Atmos/EntitySystems/AtmosphereSystem.Gases.cs

@@ -27,6 +27,8 @@ namespace Content.Server.Atmos.EntitySystems
         /// </summary>
         public float[] GasSpecificHeats => _gasSpecificHeats;
 
+        public string?[] GasReagents = new string[Atmospherics.TotalNumberOfGases];
+
         private void InitializeGases()
         {
             _gasReactions = _protoMan.EnumeratePrototypes<GasReactionPrototype>().ToArray();
@@ -37,6 +39,7 @@ namespace Content.Server.Atmos.EntitySystems
             for (var i = 0; i < GasPrototypes.Length; i++)
             {
                 _gasSpecificHeats[i] = GasPrototypes[i].SpecificHeat;
+                GasReagents[i] = GasPrototypes[i].Reagent;
             }
         }
 

Content.Server/Body/Components/BloodstreamComponent.cs

@@ -11,7 +11,7 @@ using Robust.Shared.ViewVariables;
 namespace Content.Server.Body.Components
 {
     [RegisterComponent, Friend(typeof(BloodstreamSystem))]
-    public class BloodstreamComponent : Component, IGasMixtureHolder
+    public class BloodstreamComponent : Component
     {
         /// <summary>
         ///     Max volume of internal solution storage
@@ -24,9 +24,5 @@ namespace Content.Server.Body.Components
         /// </summary>
         [ViewVariables(VVAccess.ReadWrite)]
         public Solution Solution = default!;
-
-        [ViewVariables]
-        public GasMixture Air { get; set; } = new(6)
-            { Temperature = Atmospherics.NormalBodyTemperature };
     }
 }

Content.Server/Body/Components/LungComponent.cs

@@ -1,7 +1,8 @@
-using System;
+using System.Collections.Generic;
 using Content.Server.Atmos;
 using Content.Server.Body.Systems;
 using Content.Shared.Atmos;
+using Content.Shared.Chemistry.Components;
 using Robust.Shared.Analyzers;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization.Manager.Attributes;
@@ -12,11 +13,6 @@ namespace Content.Server.Body.Components;
 [RegisterComponent, Friend(typeof(LungSystem))]
 public class LungComponent : Component
 {
-    public float AccumulatedFrametime;
-
-    [ViewVariables]
-    public TimeSpan LastGaspPopupTime;
-
     [DataField("air")]
     public GasMixture Air { get; set; } = new()
     {
@@ -24,19 +20,9 @@ public class LungComponent : Component
         Temperature = Atmospherics.NormalBodyTemperature
     };
 
-    [DataField("gaspPopupCooldown")]
+    [DataField("validReagentGases", required: true)]
-    public TimeSpan GaspPopupCooldown { get; private set; } = TimeSpan.FromSeconds(8);
+    public HashSet<Gas> ValidGases = default!;
 
     [ViewVariables]
-    public LungStatus Status { get; set; }
+    public Solution LungSolution = default!;
-
-    [DataField("cycleDelay")]
-    public float CycleDelay { get; set; } = 2;
-}
-
-public enum LungStatus
-{
-    None = 0,
-    Inhaling,
-    Exhaling
 }

Content.Server/Body/Components/RespiratorComponent.cs

@@ -1,6 +1,5 @@
-using System.Collections.Generic;
+using System;
 using Content.Server.Body.Systems;
-using Content.Shared.Atmos;
 using Content.Shared.Damage;
 using Robust.Shared.Analyzers;
 using Robust.Shared.GameObjects;
@@ -12,19 +11,26 @@ namespace Content.Server.Body.Components
     [RegisterComponent, Friend(typeof(RespiratorSystem))]
     public class RespiratorComponent : Component
     {
-        [ViewVariables]
+        /// <summary>
-        [DataField("needsGases")]
+        ///     Saturation level. Reduced by CycleDelay each tick.
-        public Dictionary<Gas, float> NeedsGases { get; set; } = new();
+        ///     Can be thought of as 'how many seconds you have until you start suffocating' in this configuration.
+        /// </summary>
+        [DataField("saturation")]
+        public float Saturation = 5.0f;
 
-        [ViewVariables]
+        /// <summary>
-        [DataField("producesGases")]
+        ///     At what level of saturation will you begin to suffocate?
-        public Dictionary<Gas, float> ProducesGases { get; set; } = new();
+        /// </summary>
+        [DataField("suffocationThreshold")]
+        public float SuffocationThreshold;
 
-        [ViewVariables]
+        [DataField("maxSaturation")]
-        [DataField("deficitGases")]
+        public float MaxSaturation = 5.0f;
-        public Dictionary<Gas, float> DeficitGases { get; set; } = new();
 
-        [ViewVariables] public bool Suffocating { get; set; }
+        [DataField("minSaturation")]
+        public float MinSaturation = -5.0f;
+
+        // TODO HYPEROXIA?
 
         [DataField("damage", required: true)]
         [ViewVariables(VVAccess.ReadWrite)]
@@ -34,6 +40,36 @@ namespace Content.Server.Body.Components
         [ViewVariables(VVAccess.ReadWrite)]
         public DamageSpecifier DamageRecovery = default!;
 
+        [DataField("gaspPopupCooldown")]
+        public TimeSpan GaspPopupCooldown { get; private set; } = TimeSpan.FromSeconds(8);
+
+        [ViewVariables]
+        public TimeSpan LastGaspPopupTime;
+
+        /// <summary>
+        ///     How many cycles in a row has the mob been under-saturated?
+        /// </summary>
+        [ViewVariables]
+        public int SuffocationCycles = 0;
+
+        /// <summary>
+        ///     How many cycles in a row does it take for the suffocation alert to pop up?
+        /// </summary>
+        [ViewVariables]
+        public int SuffocationCycleThreshold = 3;
+
+        [ViewVariables]
+        public RespiratorStatus Status = RespiratorStatus.Inhaling;
+
+        [DataField("cycleDelay")]
+        public float CycleDelay = 2.0f;
+
         public float AccumulatedFrametime;
     }
 }
+
+public enum RespiratorStatus
+{
+    Inhaling,
+    Exhaling
+}

Content.Server/Body/Systems/BloodstreamSystem.cs

@@ -44,34 +44,4 @@ public class BloodstreamSystem : EntitySystem
 
         return _solutionContainerSystem.TryAddSolution(uid, component.Solution, solution);
     }
-
-    public void PumpToxins(EntityUid uid, GasMixture to, BloodstreamComponent? blood=null, RespiratorComponent? respiration=null)
-    {
-        if (!Resolve(uid, ref blood))
-            return;
-
-        if(!Resolve(uid, ref respiration, false))
-        {
-            _atmosSystem.Merge(to, blood.Air);
-            blood.Air.Clear();
-            return;
-        }
-
-        var toxins = _respiratorSystem.Clean(uid, respiration, blood);
-        var toOld = new float[to.Moles.Length];
-        Array.Copy(to.Moles, toOld, toOld.Length);
-
-        _atmosSystem.Merge(to, toxins);
-
-        for (var i = 0; i < toOld.Length; i++)
-        {
-            var newAmount = to.GetMoles(i);
-            var oldAmount = toOld[i];
-            var delta = newAmount - oldAmount;
-
-            toxins.AdjustMoles(i, -delta);
-        }
-
-        _atmosSystem.Merge(blood.Air, toxins);
-    }
 }

Content.Server/Body/Systems/InternalsSystem.cs

@@ -0,0 +1,25 @@
+using Content.Server.Atmos.Components;
+using Content.Server.Body.Components;
+using Content.Shared.Atmos;
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.Body.Systems;
+
+public class InternalsSystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<InternalsComponent, InhaleLocationEvent>(OnInhaleLocation);
+    }
+
+    private void OnInhaleLocation(EntityUid uid, InternalsComponent component, InhaleLocationEvent args)
+    {
+        if (component.AreInternalsWorking())
+        {
+            var gasTank = Comp<GasTankComponent>(component.GasTankEntity!.Value);
+            args.Gas = gasTank.RemoveAirVolume(Atmospherics.BreathVolume);
+        }
+    }
+}

Content.Server/Body/Systems/LungSystem.cs

@@ -1,33 +1,28 @@
-using System;
+using System.Linq;
-using Content.Server.Atmos;
 using Content.Server.Atmos.Components;
 using Content.Server.Atmos.EntitySystems;
 using Content.Server.Body.Components;
-using Content.Server.Popups;
+using Content.Server.Chemistry.EntitySystems;
 using Content.Shared.Atmos;
-using Content.Shared.Body.Components;
+using Content.Shared.Chemistry.Components;
-using Content.Shared.Body.Events;
 using Content.Shared.Inventory.Events;
-using Content.Shared.MobState.Components;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
-using Robust.Shared.Localization;
+using Robust.Shared.Utility;
-using Robust.Shared.Player;
-using Robust.Shared.Timing;
 
 namespace Content.Server.Body.Systems;
 
 public class LungSystem : EntitySystem
 {
-    [Dependency] private readonly IGameTiming _gameTiming = default!;
+    [Dependency] private readonly SolutionContainerSystem _solutionContainerSystem = default!;
-    [Dependency] private readonly AtmosphereSystem _atmosSys = default!;
+    [Dependency] private readonly AtmosphereSystem _atmosphereSystem = default!;
-    [Dependency] private readonly BloodstreamSystem _bloodstreamSystem = default!;
+
-    [Dependency] private readonly PopupSystem _popupSystem = default!;
+    public static string LungSolutionName = "Lung";
 
     public override void Initialize()
     {
         base.Initialize();
-        SubscribeLocalEvent<LungComponent, AddedToBodyEvent>(OnAddedToBody);
+        SubscribeLocalEvent<LungComponent, ComponentInit>(OnComponentInit);
         SubscribeLocalEvent<BreathToolComponent, GotEquippedEvent>(OnGotEquipped);
         SubscribeLocalEvent<BreathToolComponent, GotUnequippedEvent>(OnGotUnequipped);
     }
@@ -50,175 +45,30 @@ public class LungSystem : EntitySystem
         }
     }
 
-    private void OnAddedToBody(EntityUid uid, LungComponent component, AddedToBodyEvent args)
+    private void OnComponentInit(EntityUid uid, LungComponent component, ComponentInit args)
     {
-        Inhale(uid, component.CycleDelay);
+        component.LungSolution = _solutionContainerSystem.EnsureSolution(uid, LungSolutionName);
+        component.LungSolution.MaxVolume = 100.0f;
+        component.LungSolution.CanReact = false; // No dexalin lungs
     }
 
-    public void Gasp(EntityUid uid,
+    public void GasToReagent(EntityUid uid, LungComponent lung)
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
     {
-        if (!Resolve(uid, ref lung, ref mech))
+        foreach (var gas in lung.ValidGases)
-            return;
-
-        if (_gameTiming.CurTime >= lung.LastGaspPopupTime + lung.GaspPopupCooldown)
         {
-            lung.LastGaspPopupTime = _gameTiming.CurTime;
+            var i = (int) gas;
-            _popupSystem.PopupEntity(Loc.GetString("lung-behavior-gasp"), uid, Filter.Pvs(uid));
+            var moles = lung.Air.Moles[i];
+            if (moles <= 0)
+                continue;
+            var reagent = _atmosphereSystem.GasReagents[i];
+            if (reagent == null) continue;
+
+            var amount = moles * Atmospherics.BreathMolesToReagentMultiplier;
+            _solutionContainerSystem.TryAddReagent(uid, lung.LungSolution, reagent, amount, out _);
+
+            // We don't remove the gas from the lung mix,
+            // that's the responsibility of whatever gas is being metabolized.
+            // Most things will just want to exhale again.
         }
-
-        if (mech.Body != null && TryComp((mech.Body).Owner, out MobStateComponent? mobState) && !mobState.IsAlive())
-            return;
-
-        Inhale(uid, lung.CycleDelay);
-    }
-
-    public void UpdateLung(EntityUid uid,
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
-    {
-        if (!Resolve(uid, ref lung, ref mech))
-            return;
-
-        if (mech.Body != null && EntityManager.TryGetComponent((mech.Body).Owner, out MobStateComponent? mobState) && mobState.IsCritical())
-        {
-            return;
-        }
-
-        if (lung.Status == LungStatus.None)
-        {
-            lung.Status = LungStatus.Inhaling;
-        }
-
-        lung.AccumulatedFrametime += lung.Status switch
-        {
-            LungStatus.Inhaling => 1,
-            LungStatus.Exhaling => -1,
-            _ => throw new ArgumentOutOfRangeException()
-        };
-
-        var absoluteTime = Math.Abs(lung.AccumulatedFrametime);
-        var delay = lung.CycleDelay;
-
-        if (absoluteTime < delay)
-        {
-            return;
-        }
-
-        switch (lung.Status)
-        {
-            case LungStatus.Inhaling:
-                Inhale(uid, absoluteTime);
-                lung.Status = LungStatus.Exhaling;
-                break;
-            case LungStatus.Exhaling:
-                Exhale(uid, absoluteTime);
-                lung.Status = LungStatus.Inhaling;
-                break;
-            default:
-                throw new ArgumentOutOfRangeException();
-        }
-
-        lung.AccumulatedFrametime = absoluteTime - delay;
-    }
-
-    /// <summary>
-    ///     Tries to find an air mixture to inhale from, then inhales from it.
-    /// </summary>
-    public void Inhale(EntityUid uid, float frameTime,
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
-    {
-        if (!Resolve(uid, ref lung, ref mech))
-            return;
-
-        // TODO Jesus Christ make this event based.
-        if (mech.Body != null &&
-            EntityManager.TryGetComponent((mech.Body).Owner, out InternalsComponent? internals) &&
-            internals.BreathToolEntity != null &&
-            internals.GasTankEntity != null &&
-            EntityManager.TryGetComponent(internals.BreathToolEntity, out BreathToolComponent? breathTool) &&
-            breathTool.IsFunctional &&
-            EntityManager.TryGetComponent(internals.GasTankEntity, out GasTankComponent? gasTank))
-        {
-            TakeGasFrom(uid, frameTime, gasTank.RemoveAirVolume(Atmospherics.BreathVolume), lung);
-            return;
-        }
-
-        if (_atmosSys.GetTileMixture(EntityManager.GetComponent<TransformComponent>(uid).Coordinates, true) is not { } tileAir)
-        {
-            return;
-        }
-
-        TakeGasFrom(uid, frameTime, tileAir, lung);
-    }
-
-    /// <summary>
-    ///     Inhales directly from a given mixture.
-    /// </summary>
-    public void TakeGasFrom(EntityUid uid, float frameTime, GasMixture from,
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
-    {
-        if (!Resolve(uid, ref lung, ref mech))
-            return;
-
-        var ratio = (Atmospherics.BreathVolume / from.Volume) * frameTime;
-
-        _atmosSys.Merge(lung.Air, from.RemoveRatio(ratio));
-
-        // Push to bloodstream
-        if (mech.Body == null)
-            return;
-
-        if (!EntityManager.TryGetComponent((mech.Body).Owner, out BloodstreamComponent? bloodstream))
-            return;
-
-        var to = bloodstream.Air;
-
-        _atmosSys.Merge(to, lung.Air);
-        lung.Air.Clear();
-    }
-
-    /// <summary>
-    ///     Tries to find a gas mixture to exhale to, then pushes gas to it.
-    /// </summary>
-    public void Exhale(EntityUid uid, float frameTime,
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
-    {
-        if (!Resolve(uid, ref lung, ref mech))
-            return;
-
-        if (_atmosSys.GetTileMixture(EntityManager.GetComponent<TransformComponent>(uid).Coordinates, true) is not { } tileAir)
-        {
-            return;
-        }
-
-        PushGasTo(uid, tileAir, lung, mech);
-    }
-
-    /// <summary>
-    ///     Pushes gas from the lungs to a gas mixture.
-    /// </summary>
-    public void PushGasTo(EntityUid uid, GasMixture to,
-        LungComponent? lung=null,
-        MechanismComponent? mech=null)
-    {
-        if (!Resolve(uid, ref lung, ref mech))
-            return;
-
-        // TODO: Make the bloodstream separately pump toxins into the lungs, making the lungs' only job to empty.
-        if (mech.Body == null)
-            return;
-
-        if (!EntityManager.TryGetComponent((mech.Body).Owner, out BloodstreamComponent? bloodstream))
-            return;
-
-        _bloodstreamSystem.PumpToxins((mech.Body).Owner, lung.Air, bloodstream);
-
-        var lungRemoved = lung.Air.RemoveRatio(0.5f);
-        _atmosSys.Merge(to, lungRemoved);
     }
 }

Content.Server/Body/Systems/MetabolizerSystem.cs

@@ -77,6 +77,8 @@ namespace Content.Server.Body.Systems
             // First step is get the solution we actually care about
             Solution? solution = null;
             EntityUid? solutionEntityUid = null;
+            EntityUid? bodyEntityUid = mech?.Body?.Owner;
+
             SolutionContainerManagerComponent? manager = null;
 
             if (meta.SolutionOnBody)
@@ -144,6 +146,10 @@ namespace Content.Server.Body.Systems
                     if (entry.MetabolismRate > mostToRemove)
                         mostToRemove = entry.MetabolismRate;
 
+                    mostToRemove *= group.MetabolismRateModifier;
+
+                    mostToRemove = FixedPoint2.Clamp(mostToRemove, 0, reagent.Quantity);
+
                     // if it's possible for them to be dead, and they are,
                     // then we shouldn't process any effects, but should probably
                     // still remove reagents
@@ -153,7 +159,8 @@ namespace Content.Server.Body.Systems
                             continue;
                     }
 
-                    var args = new ReagentEffectArgs(solutionEntityUid.Value, (meta).Owner, solution, proto, entry.MetabolismRate,
+                    var actualEntity = bodyEntityUid != null ? bodyEntityUid.Value : solutionEntityUid.Value;
+                    var args = new ReagentEffectArgs(actualEntity, (meta).Owner, solution, proto, mostToRemove,
                         EntityManager, null);
 
                     // do all effects, if conditions apply
@@ -164,9 +171,8 @@ namespace Content.Server.Body.Systems
 
                         if (effect.ShouldLog)
                         {
-                            var entity = args.SolutionEntity;
                             _logSystem.Add(LogType.ReagentEffect, effect.LogImpact,
-                                $"Metabolism effect {effect.GetType().Name:effect} of reagent {args.Reagent.Name:reagent} applied on entity {entity} at {Transform(entity).Coordinates:coordinates}");
+                                $"Metabolism effect {effect.GetType().Name:effect} of reagent {args.Reagent.Name:reagent} applied on entity {actualEntity:entity} at {Transform(actualEntity).Coordinates:coordinates}");
                         }
 
                         effect.Effect(args);

Content.Server/Body/Systems/RespiratorSystem.cs

@@ -1,9 +1,10 @@
 using System;
-using System.Collections.Generic;
 using System.Linq;
 using Content.Server.Administration.Logs;
 using Content.Server.Atmos;
+using Content.Server.Atmos.EntitySystems;
 using Content.Server.Body.Components;
+using Content.Server.Popups;
 using Content.Shared.Alert;
 using Content.Shared.Atmos;
 using Content.Shared.Body.Components;
@@ -13,6 +14,9 @@ using Content.Shared.MobState.Components;
 using JetBrains.Annotations;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+using Robust.Shared.Player;
+using Robust.Shared.Timing;
 
 namespace Content.Server.Body.Systems
 {
@@ -23,14 +27,25 @@ namespace Content.Server.Body.Systems
         [Dependency] private readonly AdminLogSystem _logSys = default!;
         [Dependency] private readonly BodySystem _bodySystem = default!;
         [Dependency] private readonly LungSystem _lungSystem = default!;
+        [Dependency] private readonly AtmosphereSystem _atmosSys = default!;
+        [Dependency] private readonly PopupSystem _popupSystem = default!;
         [Dependency] private readonly AlertsSystem _alertsSystem = default!;
+        [Dependency] private readonly IGameTiming _gameTiming = default!;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            // We want to process lung reagents before we inhale new reagents.
+            UpdatesAfter.Add(typeof(MetabolizerSystem));
+        }
 
         public override void Update(float frameTime)
         {
             base.Update(frameTime);
 
-            foreach (var (respirator, blood, body) in
+            foreach (var (respirator, body) in
-                     EntityManager.EntityQuery<RespiratorComponent, BloodstreamComponent, SharedBodyComponent>())
+                     EntityManager.EntityQuery<RespiratorComponent, SharedBodyComponent>())
             {
                 var uid = respirator.Owner;
                 if (!EntityManager.TryGetComponent<MobStateComponent>(uid, out var state) ||
@@ -41,211 +56,142 @@ namespace Content.Server.Body.Systems
 
                 respirator.AccumulatedFrametime += frameTime;
 
-                if (respirator.AccumulatedFrametime < 1)
+                if (respirator.AccumulatedFrametime < respirator.CycleDelay)
-                {
                     continue;
+                respirator.AccumulatedFrametime -= respirator.CycleDelay;
+                UpdateSaturation(respirator.Owner, -respirator.CycleDelay, respirator);
+
+                switch (respirator.Status)
+                {
+                    case RespiratorStatus.Inhaling:
+                        Inhale(uid, body);
+                        respirator.Status = RespiratorStatus.Exhaling;
+                        break;
+                    case RespiratorStatus.Exhaling:
+                        Exhale(uid, body);
+                        respirator.Status = RespiratorStatus.Inhaling;
+                        break;
                 }
 
-                ProcessGases(uid, respirator, blood, body);
+                if (respirator.Saturation < respirator.SuffocationThreshold)
-
-                respirator.AccumulatedFrametime -= 1;
-
-                if (SuffocatingPercentage(respirator) > 0)
                 {
+                    if (_gameTiming.CurTime >= respirator.LastGaspPopupTime + respirator.GaspPopupCooldown)
+                    {
+                        respirator.LastGaspPopupTime = _gameTiming.CurTime;
+                        _popupSystem.PopupEntity(Loc.GetString("lung-behavior-gasp"), uid, Filter.Pvs(uid));
+                    }
+
                     TakeSuffocationDamage(uid, respirator);
+                    respirator.SuffocationCycles += 1;
                     continue;
                 }
 
                 StopSuffocation(uid, respirator);
+                respirator.SuffocationCycles = 0;
             }
         }
 
-        private Dictionary<Gas, float> NeedsAndDeficit(RespiratorComponent respirator)
+        public void Inhale(EntityUid uid, SharedBodyComponent? body=null)
         {
-            var needs = new Dictionary<Gas, float>(respirator.NeedsGases);
+            if (!Resolve(uid, ref body, false))
-            foreach (var (gas, amount) in respirator.DeficitGases)
-            {
-                var newAmount = (needs.GetValueOrDefault(gas) + amount);
-                needs[gas] = newAmount;
-            }
-
-            return needs;
-        }
-
-        private void ClampDeficit(RespiratorComponent respirator)
-        {
-            var deficitGases = new Dictionary<Gas, float>(respirator.DeficitGases);
-
-            foreach (var (gas, deficit) in deficitGases)
-            {
-                if (!respirator.NeedsGases.TryGetValue(gas, out var need))
-                {
-                    respirator.DeficitGases.Remove(gas);
-                    continue;
-                }
-
-                if (deficit > need)
-                {
-                    respirator.DeficitGases[gas] = need;
-                }
-            }
-        }
-
-        private float SuffocatingPercentage(RespiratorComponent respirator)
-        {
-            var total = 0f;
-
-            foreach (var (gas, deficit) in respirator.DeficitGases)
-            {
-                var lack = 1f;
-                if (respirator.NeedsGases.TryGetValue(gas, out var needed))
-                {
-                    lack = deficit / needed;
-                }
-
-                total += lack / Atmospherics.TotalNumberOfGases;
-            }
-
-            return total;
-        }
-
-        private float GasProducedMultiplier(RespiratorComponent respirator, Gas gas, float usedAverage)
-        {
-            if (!respirator.ProducesGases.TryGetValue(gas, out var produces))
-            {
-                return 0;
-            }
-
-            if (!respirator.NeedsGases.TryGetValue(gas, out var needs))
-            {
-                needs = 1;
-            }
-
-            return needs * produces * usedAverage;
-        }
-
-        private Dictionary<Gas, float> GasProduced(RespiratorComponent respirator, float usedAverage)
-        {
-            return respirator.ProducesGases.ToDictionary(pair => pair.Key, pair => GasProducedMultiplier(respirator, pair.Key, usedAverage));
-        }
-
-        private void ProcessGases(EntityUid uid, RespiratorComponent respirator,
-            BloodstreamComponent? bloodstream,
-            SharedBodyComponent? body)
-        {
-            if (!Resolve(uid, ref bloodstream, ref body, false))
                 return;
 
-            var lungs = _bodySystem.GetComponentsOnMechanisms<LungComponent>(uid, body).ToArray();
+            var organs = _bodySystem.GetComponentsOnMechanisms<LungComponent>(uid, body).ToArray();
 
-            var needs = NeedsAndDeficit(respirator);
+            // Inhale gas
-            var used = 0f;
+            var ev = new InhaleLocationEvent();
+            RaiseLocalEvent(uid, ev, false);
 
-            foreach (var (lung, mech) in lungs)
+            if (ev.Gas == null)
             {
-                _lungSystem.UpdateLung(lung.Owner, lung, mech);
+                ev.Gas = _atmosSys.GetTileMixture(Transform(uid).Coordinates);
+                if (ev.Gas == null) return;
             }
 
-            foreach (var (gas, amountNeeded) in needs)
+            var ratio = (Atmospherics.BreathVolume / ev.Gas.Volume);
+            var actualGas = ev.Gas.RemoveRatio(ratio);
+
+            var lungRatio = 1.0f / organs.Length;
+            var gas = organs.Length == 1 ? actualGas : actualGas.RemoveRatio(lungRatio);
+            foreach (var (lung, _) in organs)
             {
-                var bloodstreamAmount = bloodstream.Air.GetMoles(gas);
+                // Merge doesn't remove gas from the giver.
-                var deficit = 0f;
+                _atmosSys.Merge(lung.Air, gas);
+                _lungSystem.GasToReagent(lung.Owner, lung);
+            }
+        }
 
-                if (bloodstreamAmount < amountNeeded)
+        public void Exhale(EntityUid uid, SharedBodyComponent? body=null)
-                {
+        {
-                    // Panic inhale
+            if (!Resolve(uid, ref body, false))
-                    foreach (var (lung, mech) in lungs)
+                return;
-                    {
-                        _lungSystem.Gasp((lung).Owner, lung, mech);
-                    }
 
-                    bloodstreamAmount = bloodstream.Air.GetMoles(gas);
+            var organs = _bodySystem.GetComponentsOnMechanisms<LungComponent>(uid, body).ToArray();
 
-                    deficit = Math.Max(0, amountNeeded - bloodstreamAmount);
+            // exhale gas
 
-                    if (deficit > 0)
+            var ev = new ExhaleLocationEvent();
-                    {
+            RaiseLocalEvent(uid, ev, false);
-                        bloodstream.Air.SetMoles(gas, 0);
-                    }
-                    else
-                    {
-                        bloodstream.Air.AdjustMoles(gas, -amountNeeded);
-                    }
-                }
-                else
-                {
-                    bloodstream.Air.AdjustMoles(gas, -amountNeeded);
-                }
 
-                respirator.DeficitGases[gas] = deficit;
+            if (ev.Gas == null)
-
+            {
-                used += (amountNeeded - deficit) / amountNeeded;
+                ev.Gas = _atmosSys.GetTileMixture(Transform(uid).Coordinates);
+                if (ev.Gas == null) return;
             }
 
-            var produced = GasProduced(respirator, used / needs.Count);
+            var outGas = new GasMixture(ev.Gas.Volume);
-
+            foreach (var (lung, _) in organs)
-            foreach (var (gas, amountProduced) in produced)
             {
-                bloodstream.Air.AdjustMoles(gas, amountProduced);
+                _atmosSys.Merge(outGas, lung.Air);
+                lung.Air.Clear();
+                lung.LungSolution.RemoveAllSolution();
             }
 
-            ClampDeficit(respirator);
+            _atmosSys.Merge(ev.Gas, outGas);
         }
 
         private void TakeSuffocationDamage(EntityUid uid, RespiratorComponent respirator)
         {
-            if (!respirator.Suffocating)
+            if (respirator.SuffocationCycles == 2)
                 _logSys.Add(LogType.Asphyxiation, $"{ToPrettyString(uid):entity} started suffocating");
 
-            respirator.Suffocating = true;
+            if (respirator.SuffocationCycles >= respirator.SuffocationCycleThreshold)
-
+            {
-            _alertsSystem.ShowAlert(uid, AlertType.LowOxygen);
+                _alertsSystem.ShowAlert(uid, AlertType.LowOxygen);
+            }
 
             _damageableSys.TryChangeDamage(uid, respirator.Damage, true, false);
         }
 
         private void StopSuffocation(EntityUid uid, RespiratorComponent respirator)
         {
-            if (respirator.Suffocating)
+            if (respirator.SuffocationCycles >= 2)
                 _logSys.Add(LogType.Asphyxiation, $"{ToPrettyString(uid):entity} stopped suffocating");
 
-            respirator.Suffocating = false;
-
             _alertsSystem.ClearAlert(uid, AlertType.LowOxygen);
 
             _damageableSys.TryChangeDamage(uid, respirator.DamageRecovery, true);
         }
 
-        public GasMixture Clean(EntityUid uid, RespiratorComponent respirator, BloodstreamComponent bloodstream)
+        public void UpdateSaturation(EntityUid uid, float amount,
+            RespiratorComponent? respirator = null)
         {
-            var gasMixture = new GasMixture(bloodstream.Air.Volume)
+            if (!Resolve(uid, ref respirator, false))
-            {
+                return;
-                Temperature = bloodstream.Air.Temperature
-            };
 
-            for (Gas gas = 0; gas < (Gas) Atmospherics.TotalNumberOfGases; gas++)
+            respirator.Saturation += amount;
-            {
+            respirator.Saturation =
-                float amount;
+                Math.Clamp(respirator.Saturation, respirator.MinSaturation, respirator.MaxSaturation);
-                var molesInBlood = bloodstream.Air.GetMoles(gas);
-
-                if (!respirator.NeedsGases.TryGetValue(gas, out var needed))
-                {
-                    amount = molesInBlood;
-                }
-                else
-                {
-                    var overflowThreshold = needed * 5f;
-
-                    amount = molesInBlood > overflowThreshold
-                        ? molesInBlood - overflowThreshold
-                        : 0;
-                }
-
-                gasMixture.AdjustMoles(gas, amount);
-                bloodstream.Air.AdjustMoles(gas, -amount);
-            }
-
-            return gasMixture;
         }
     }
 }
+
+public class InhaleLocationEvent : EntityEventArgs
+{
+    public GasMixture? Gas;
+}
+
+public class ExhaleLocationEvent : EntityEventArgs
+{
+    public GasMixture? Gas;
+}

Content.Server/Chemistry/ReagentEffects/AdjustAlert.cs

@@ -0,0 +1,46 @@
+using System;
+using Content.Shared.Alert;
+using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Timing;
+
+namespace Content.Server.Chemistry.ReagentEffects;
+
+public class AdjustAlert : ReagentEffect
+{
+    [DataField("alertType", required: true)]
+    public AlertType Type;
+
+    [DataField("clear")]
+    public bool Clear;
+
+    [DataField("cooldown")]
+    public bool Cooldown;
+
+    [DataField("time")]
+    public float Time;
+
+    public override void Effect(ReagentEffectArgs args)
+    {
+        var alertSys = EntitySystem.Get<AlertsSystem>();
+        if (args.EntityManager.HasComponent<AlertsComponent>(args.SolutionEntity))
+        {
+            if (Clear)
+            {
+                alertSys.ClearAlert(args.SolutionEntity, Type);
+            }
+            else
+            {
+                (TimeSpan, TimeSpan)? cooldown = null;
+                if (Cooldown)
+                {
+                    var timing = IoCManager.Resolve<IGameTiming>();
+                    cooldown = (timing.CurTime, timing.CurTime + TimeSpan.FromSeconds(Time));
+                }
+                alertSys.ShowAlert(args.SolutionEntity, Type, cooldown: cooldown);
+            }
+        }
+    }
+}

Content.Server/Chemistry/ReagentEffects/ModifyLungGas.cs

@@ -0,0 +1,24 @@
+using System.Collections.Generic;
+using Content.Server.Body.Components;
+using Content.Shared.Atmos;
+using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.Serialization.Manager.Attributes;
+
+namespace Content.Server.Chemistry.ReagentEffects;
+
+public class ModifyLungGas : ReagentEffect
+{
+    [DataField("ratios", required: true)]
+    private Dictionary<Gas, float> _ratios = default!;
+
+    public override void Effect(ReagentEffectArgs args)
+    {
+        if (args.EntityManager.TryGetComponent<LungComponent>(args.OrganEntity, out var lung))
+        {
+            foreach (var (gas, ratio) in _ratios)
+            {
+                lung.Air.Moles[(int) gas] += (ratio * args.Quantity.Float()) / Atmospherics.BreathMolesToReagentMultiplier;
+            }
+        }
+    }
+}

Content.Server/Chemistry/ReagentEffects/Oxygenate.cs

@@ -0,0 +1,22 @@
+using Content.Server.Body.Components;
+using Content.Server.Body.Systems;
+using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization.Manager.Attributes;
+
+namespace Content.Server.Chemistry.ReagentEffects;
+
+public class Oxygenate : ReagentEffect
+{
+    [DataField("factor")]
+    public float Factor = 1f;
+
+    public override void Effect(ReagentEffectArgs args)
+    {
+        if (args.EntityManager.TryGetComponent<RespiratorComponent>(args.SolutionEntity, out var resp))
+        {
+            var respSys = EntitySystem.Get<RespiratorSystem>();
+            respSys.UpdateSaturation(resp.Owner, args.Quantity.Float() * Factor, resp);
+        }
+    }
+}

Content.Shared/Alert/AlertCategory.cs

@@ -12,5 +12,6 @@ public enum AlertCategory
     Health,
     Piloting,
     Hunger,
-    Thirst
+    Thirst,
-}
+    Toxins
+}

Content.Shared/Alert/AlertType.cs

@@ -31,6 +31,7 @@
         Pulled,
         Pulling,
         Magboots,
+        Toxins,
         Debug1,
         Debug2,
         Debug3,

Content.Shared/Atmos/Atmospherics.cs

@@ -255,11 +255,10 @@ namespace Content.Shared.Atmos
         /// </summary>
         public const float NormalBodyTemperature = 37f;
 
-        public const float HumanNeededOxygen = MolesCellStandard * BreathPercentage * 0.16f;
+        /// <summary>
-
+        ///     I hereby decree. This is Arbitrary Suck my Dick
-        public const float HumanProducedOxygen = HumanNeededOxygen * 0.75f;
+        /// </summary>
-
+        public const float BreathMolesToReagentMultiplier = 1144;
-        public const float HumanProducedCarbonDioxide = HumanNeededOxygen * 0.25f;
 
         #region Pipes
 

Content.Shared/Atmos/Prototypes/GasPrototype.cs

@@ -1,5 +1,7 @@
-using Robust.Shared.Prototypes;
+using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.Prototypes;
 using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
 using Robust.Shared.ViewVariables;
 
 namespace Content.Shared.Atmos.Prototypes
@@ -70,6 +72,12 @@ namespace Content.Shared.Atmos.Prototypes
         [DataField("overlayPath")]
         public string OverlayPath { get; } = string.Empty;
 
+        /// <summary>
+        /// The reagent that this gas will turn into when inhaled.
+        /// </summary>
+        [DataField("reagent", customTypeSerializer:typeof(PrototypeIdSerializer<ReagentPrototype>))]
+        public string? Reagent { get; } = default!;
+
         [DataField("color")] public string Color { get; } = string.Empty;
     }
 }

Resources/Prototypes/Alerts/alerts.yml

@@ -25,7 +25,16 @@
     sprite: /Textures/Interface/Alerts/breathing.rsi
     state: not_enough_oxy
   name: "[color=red]Low Oxygen[/color]"
-  description: "There is not [color=red]not enough oxygen[/color] in the air you are breathing. Put on [color=green]internals[/color]."
+  description: "There is [color=red]not enough oxygen[/color] in the air you are breathing. Put on [color=green]internals[/color]."
+
+- type: alert
+  alertType: Toxins
+  category: Toxins
+  icon:
+    sprite: /Textures/Interface/Alerts/breathing.rsi
+    state: too_much_tox
+  name: "[color=red]High Toxin Level[/color]"
+  description: "There are [color=red]too many toxins[/color] in the air you are breathing. Put on [color=green]internals[/color] or get away."
 
 - type: alert
   alertType: LowPressure

Resources/Prototypes/Atmospherics/gases.yml

@@ -5,6 +5,7 @@
   heatCapacityRatio: 1.4
   molarMass: 32
   color: 2887E8
+  reagent: Oxygen
 
 - type: gas
   id: 1
@@ -13,6 +14,7 @@
   heatCapacityRatio: 1.4
   molarMass: 28
   color: DA1010
+  reagent: Nitrogen
 
 - type: gas
   id: 2
@@ -21,6 +23,7 @@
   heatCapacityRatio: 1.3
   molarMass: 44
   color: 4e4e4e
+  reagent: CarbonDioxide
 
 - type: gas
   id: 3
@@ -31,6 +34,7 @@
   gasOverlaySprite: /Textures/Effects/atmospherics.rsi
   gasOverlayState: plasma
   color: FF3300
+  reagent: Plasma
 
 - type: gas
   id: 4
@@ -41,6 +45,7 @@
   gasOverlaySprite: /Textures/Effects/atmospherics.rsi
   gasOverlayState: tritium
   color: 13FF4B
+  reagent: Tritium
 
 - type: gas
   id: 5
@@ -51,3 +56,4 @@
   gasOverlaySprite: /Textures/Effects/atmospherics.rsi
   gasOverlayState: water_vapor
   color: bffffd
+  reagent: Water

Resources/Prototypes/Body/Mechanisms/human.yml

@@ -100,6 +100,19 @@
     size: 1
     compatibility: Biological
   - type: Lung
+    validReagentGases:
+    - Oxygen
+    - Plasma
+    - Tritium
+    - CarbonDioxide
+  - type: Metabolizer
+    removeEmpty: true
+    solutionOnBody: false
+    solution: "Lung"
+    metabolizerTypes: [ Human ]
+    groups:
+    - id: Gas
+      rateModifier: 100.0
 
 - type: entity
   id: OrganHumanHeart

Resources/Prototypes/Body/Mechanisms/slime.yml

@@ -11,7 +11,6 @@
     - type: Mechanism
       size: 5
       compatibility: Slime
-    - type: Lung
     - type: Brain
     - type: Stomach
       maxVolume: 250

Resources/Prototypes/Body/Parts/animal.yml

@@ -82,6 +82,19 @@
     size: 1
     compatibility: Biological
   - type: Lung
+    validReagentGases:
+    - Oxygen
+    - Plasma
+    - Tritium
+    - CarbonDioxide
+  - type: Metabolizer
+    removeEmpty: true
+    solutionOnBody: false
+    solution: "Lung"
+    metabolizerTypes: [ Animal ]
+    groups:
+    - id: Gas
+      rateModifier: 100.0
 
 - type: entity
   id: OrganAnimalStomach

Resources/Prototypes/Chemistry/metabolism_groups.yml

@@ -16,3 +16,7 @@
 
 - type: metabolismGroup
   id: Drink
+
+# Used for gases that have effects on being inhaled
+- type: metabolismGroup
+  id: Gas

Resources/Prototypes/Entities/Mobs/NPCs/simplemob.yml

@@ -152,17 +152,12 @@
     normalBodyTemperature: 310.15
     thermalRegulationTemperatureThreshold: 25
   - type: Respirator
-    needsGases:
-      Oxygen: 0.00060763888
-    producesGases:
-      Oxygen: 0.00045572916
-      CarbonDioxide: 0.00015190972
     damage:
       types:
-        Asphyxiation: 1
+        Asphyxiation: 3
     damageRecovery:
       types:
-        Asphyxiation: -1
+        Asphyxiation: -1.5
   - type: Temperature
     heatDamageThreshold: 360
     coldDamageThreshold: 260

Resources/Prototypes/Entities/Mobs/NPCs/xeno.yml

@@ -42,10 +42,10 @@
   - type: Respirator
     damage:
       types:
-        Asphyxiation: 1
+        Asphyxiation: 3
     damageRecovery:
       types:
-        Asphyxiation: -1
+        Asphyxiation: -1.5
   - type: UnarmedCombat
     range: 1.5
     arcwidth: 0

Resources/Prototypes/Entities/Mobs/Player/human.yml

@@ -11,6 +11,13 @@
     context: "human"
   - type: PlayerMobMover
   - type: PlayerInputMover
+  - type: Respirator
+    damage:
+      types:
+        Asphyxiation: 3
+    damageRecovery:
+      types:
+        Asphyxiation: -1.5
   - type: Alerts
   - type: Actions
     innateActions:

Resources/Prototypes/Entities/Mobs/Species/dwarf.yml

@@ -9,6 +9,13 @@
   - type: Icon
     sprite: Mobs/Species/Slime/parts.rsi
     state: full
+  - type: Respirator
+    damage:
+      types:
+        Asphyxiation: 3
+    damageRecovery:
+      types:
+        Asphyxiation: -1.5
   - type: Sprite
     netsync: false
     noRot: true

Resources/Prototypes/Entities/Mobs/Species/human.yml

@@ -199,18 +199,6 @@
     shiveringHeatRegulation: 2000
     normalBodyTemperature: 310.15
     thermalRegulationTemperatureThreshold: 25
-  - type: Respirator
-    needsGases:
-      Oxygen: 0.00060763888
-    producesGases:
-      Oxygen: 0.00045572916
-      CarbonDioxide: 0.00015190972
-    damage:
-      types:
-        Asphyxiation: 1
-    damageRecovery:
-      types:
-        Asphyxiation: -1
   - type: Internals
   - type: MobState
     thresholds:

Resources/Prototypes/Entities/Mobs/Species/vox.yml

@@ -83,18 +83,14 @@
   - type: Body
     template: HumanoidTemplate
     preset: VoxPreset
+  # TODO Vox nitrogen
   - type: Respirator
-    needsGases:
-      Nitrogen: 0.00060763888
-    producesGases:
-      Nitrogen: 0.00045572916
-      CarbonDioxide: 0.00015190972
     damage:
       types:
-        Asphyxiation: 1
+        Asphyxiation: 3
     damageRecovery:
       types:
-        Asphyxiation: -1
+        Asphyxiation: -1.5
 #  - type: Appearance
 #    visuals:
 #      - type: RotationVisualizer

Resources/Prototypes/Reagents/elements.yml

@@ -134,26 +134,6 @@
           types:
             Poison: 2
 
-- type: reagent
-  id: Nitrogen
-  name: nitrogen
-  group: Elements
-  desc: A colorless, odorless unreactive gas. Highly stable.
-  physicalDesc: gaseous
-  color: "#808080"
-  boilingPoint: -195.8
-  meltingPoint: -210.0
-
-- type: reagent
-  id: Oxygen
-  name: oxygen
-  group: Elements
-  desc: An oxidizing, colorless gas.
-  physicalDesc: gaseous
-  color: "#808080"
-  boilingPoint: -183.0
-  meltingPoint: -218.4
-
 - type: reagent
   id: Potassium
   name: potassium

Resources/Prototypes/Reagents/gases.yml

@@ -0,0 +1,121 @@
+- type: reagent
+  id: Oxygen
+  name: oxygen
+  desc: An oxidizing, colorless gas.
+  physicalDesc: gaseous
+  color: "#808080"
+  boilingPoint: -183.0
+  meltingPoint: -218.4
+  metabolisms:
+    Gas:
+      effects:
+      - !type:Oxygenate
+        conditions:
+        - !type:OrganType
+          type: Human
+      - !type:Oxygenate
+        conditions:
+        - !type:OrganType
+          type: Animal
+      # Convert Oxygen into CO2.
+      - !type:ModifyLungGas
+        ratios:
+          CarbonDioxide: 1.0
+          Oxygen: -1.0
+
+- type: reagent
+  id: Plasma
+  name: plasma
+  desc: Funky, space-magic pixie dust. You probably shouldn't eat this, but we both know you will anyways.
+  physicalDesc: gaseous
+  color: "#7e009e"
+  boilingPoint: -127.3 # Random values picked between the actual values for CO2 and O2
+  meltingPoint: -186.4
+  tileReactions:
+  - !type:FlammableTileReaction
+    temperatureMultiplier: 1.5
+  metabolisms:
+    Poison:
+      effects:
+      - !type:HealthChange
+        damage:
+          types:
+            Poison: 3
+      - !type:AdjustReagent
+        reagent: Inaprovaline
+        amount: -2.0
+    Gas:
+      effects:
+      - !type:HealthChange
+        scaleByQuantity: true
+        ignoreResistances: true
+        damage:
+          types:
+            Poison:
+              1
+      # Cant be added until I add metabolism effects on reagent removal
+      #- !type:AdjustAlert
+      #  alertType: Toxins
+  reactiveEffects:
+    Flammable:
+      methods: [ Touch ]
+      effects:
+      - !type:FlammableReaction
+
+- type: reagent
+  id: Tritium
+  name: tritium
+  desc: Radioactive space-magic pixie dust.
+  physicalDesc: ionizing
+  color: "#66ff33"
+  tileReactions:
+  - !type:FlammableTileReaction
+    temperatureMultiplier: 2.0
+  metabolisms:
+    Poison:
+      effects:
+      - !type:HealthChange
+        damage:
+          types:
+            Radiation: 3
+    Gas:
+      effects:
+      - !type:HealthChange
+        scaleByQuantity: true
+        ignoreResistances: true
+        damage:
+          types:
+            Radiation:
+              1
+      # Cant be added until I add metabolism effects on reagent removal
+      #- !type:AdjustAlert
+      #  alertType: Toxins
+
+- type: reagent
+  id: CarbonDioxide
+  name: carbon dioxide
+  desc: You have genuinely no idea what this is.
+  physicalDesc: odorless
+  color: "#66ff33"
+  metabolisms:
+    Gas:
+      effects:
+      - !type:HealthChange
+        scaleByQuantity: true
+        ignoreResistances: true
+        damage:
+          types:
+            Poison:
+              0.2
+      # Cant be added until I add metabolism effects on reagent removal
+      #- !type:AdjustAlert
+      #  alertType: CarbonDioxide
+
+- type: reagent
+  id: Nitrogen
+  name: nitrogen
+  desc: A colorless, odorless unreactive gas. Highly stable.
+  physicalDesc: gaseous
+  color: "#808080"
+  boilingPoint: -195.8
+  meltingPoint: -210.0

Resources/Prototypes/Reagents/toxins.yml

@@ -133,35 +133,6 @@
         type: Local
         messages: [ "generic-reagent-effect-burning-insides" ]
         probability: 0.33
-  # TODO MIRROR acid!
-
-- type: reagent
-  id: Plasma
-  name: plasma
-  group: Toxins
-  desc: Funky, space-magic pixie dust. You probably shouldn't eat this, but we both know you will anyways.
-  physicalDesc: gaseous
-  color: "#7e009e"
-  boilingPoint: -127.3 # Random values picked between the actual values for CO2 and O2
-  meltingPoint: -186.4
-  tileReactions:
-  - !type:FlammableTileReaction
-    temperatureMultiplier: 1.5
-  metabolisms:
-    Poison:
-      effects:
-      - !type:HealthChange
-        damage:
-          types:
-            Poison: 3
-      - !type:AdjustReagent
-        reagent: Inaprovaline
-        amount: -2.0
-  reactiveEffects:
-    Flammable:
-      methods: [ Touch ]
-      effects:
-      - !type:FlammableReaction
 
 - type: reagent
   id: UnstableMutagen