Hopefully fix atmos issues

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

@@ -10,7 +10,6 @@ namespace Content.Server.Atmos.EntitySystems
     public sealed partial class AtmosphereSystem
     {
         [Dependency] private readonly IPrototypeManager _protoMan = default!;
-        [Dependency] private readonly GenericGasReactionSystem _reaction = default!;
 
         private GasReactionPrototype[] _gasReactions = Array.Empty<GasReactionPrototype>();
         private float[] _gasSpecificHeats = new float[Atmospherics.TotalNumberOfGases];
@@ -123,7 +122,7 @@ public void Merge(GasMixture receiver, GasMixture giver)
                 var receiverHeatCapacity = GetHeatCapacity(receiver);
                 var giverHeatCapacity = GetHeatCapacity(giver);
                 var combinedHeatCapacity = receiverHeatCapacity + giverHeatCapacity;
-                if (combinedHeatCapacity > 0f)
+                if (combinedHeatCapacity > Atmospherics.MinimumHeatCapacity)
                 {
                     receiver.Temperature = (GetThermalEnergy(giver, giverHeatCapacity) + GetThermalEnergy(receiver, receiverHeatCapacity)) / combinedHeatCapacity;
                 }
@@ -167,7 +166,7 @@ public void DivideInto(GasMixture source, List<GasMixture> receivers)
                         sourceHeatCapacity ??= GetHeatCapacity(source);
                         var receiverHeatCapacity = GetHeatCapacity(receiver);
                         var combinedHeatCapacity = receiverHeatCapacity + sourceHeatCapacity.Value * fraction;
-                        if (combinedHeatCapacity > 0f)
+                        if (combinedHeatCapacity > Atmospherics.MinimumHeatCapacity)
                             receiver.Temperature = (GetThermalEnergy(source, sourceHeatCapacity.Value * fraction) + GetThermalEnergy(receiver, receiverHeatCapacity)) / combinedHeatCapacity;
                     }
                 }
@@ -347,7 +346,7 @@ public ReactionResult React(GasMixture mixture, IGasMixtureHolder? holder)
                     break;
             }
 
-            return _reaction.ReactAll(GasReactions, mixture, holder);
+            return reaction;
         }
 
         public enum GasCompareResult

Content.Server/Atmos/GasMixture.cs

@@ -4,6 +4,7 @@
 using Content.Server.Atmos.Reactions;
 using Content.Shared.Atmos;
 using Robust.Shared.Serialization;
+using Robust.Shared.Utility;
 
 namespace Content.Server.Atmos
 {
@@ -58,8 +59,9 @@ public float Temperature
             get => _temperature;
             set
             {
+                DebugTools.Assert(!float.IsNaN(_temperature));
                 if (Immutable) return;
-                _temperature = MathF.Max(value, Atmospherics.TCMB);
+                _temperature = MathF.Min(MathF.Max(value, Atmospherics.TCMB), Atmospherics.Tmax);
             }
         }
 
@@ -120,12 +122,9 @@ public void AdjustMoles(int gasId, float quantity)
                 if (!float.IsFinite(quantity))
                     throw new ArgumentException($"Invalid quantity \"{quantity}\" specified!", nameof(quantity));
 
-                Moles[gasId] += quantity;
-
-                var moles = Moles[gasId];
-
-                if (!float.IsFinite(moles) || float.IsNegative(moles))
-                    throw new Exception($"Invalid mole quantity \"{moles}\" in gas Id {gasId} after adjusting moles with \"{quantity}\"!");
+                // Clamping is needed because x - x can be negative with floating point numbers. If we don't
+                // clamp here, the caller always has to call GetMoles(), clamp, then SetMoles().
+                Moles[gasId] = MathF.Max(Moles[gasId] + quantity, 0);
             }
         }
 

Content.Server/Atmos/Reactions/AmmoniaOxygenReaction.cs

@@ -0,0 +1,33 @@
+using Content.Server.Atmos.EntitySystems;
+using Content.Shared.Atmos;
+using JetBrains.Annotations;
+
+namespace Content.Server.Atmos.Reactions;
+
+[UsedImplicitly]
+public sealed partial class AmmoniaOxygenReaction : IGasReactionEffect
+{
+    public ReactionResult React(GasMixture mixture, IGasMixtureHolder? holder, AtmosphereSystem atmosphereSystem, float heatScale)
+    {
+        var nAmmonia = mixture.GetMoles(Gas.Ammonia);
+        var nOxygen = mixture.GetMoles(Gas.Oxygen);
+        var nTotal = mixture.TotalMoles;
+
+        // Concentration-dependent reaction rate
+        var fAmmonia = nAmmonia/nTotal;
+        var fOxygen = nOxygen/nTotal;
+        var rate = MathF.Pow(fAmmonia, 2) * MathF.Pow(fOxygen, 2);
+
+        var deltaMoles = nAmmonia / Atmospherics.AmmoniaOxygenReactionRate * 2 * rate;
+
+        if (deltaMoles <= 0 || nAmmonia - deltaMoles < 0)
+            return ReactionResult.NoReaction;
+
+        mixture.AdjustMoles(Gas.Ammonia, -deltaMoles);
+        mixture.AdjustMoles(Gas.Oxygen, -deltaMoles);
+        mixture.AdjustMoles(Gas.NitrousOxide, deltaMoles / 2);
+        mixture.AdjustMoles(Gas.WaterVapor, deltaMoles * 1.5f);
+
+        return ReactionResult.Reacting;
+    }
+}

Content.Server/Atmos/Reactions/FrezonCoolantReaction.cs

@@ -0,0 +1,58 @@
+using Content.Server.Atmos.EntitySystems;
+using Content.Shared.Atmos;
+using JetBrains.Annotations;
+
+namespace Content.Server.Atmos.Reactions;
+
+/// <summary>
+///     Takes in nitrogen and frezon and cools down the surrounding area.
+/// </summary>
+[UsedImplicitly]
+public sealed partial class FrezonCoolantReaction : IGasReactionEffect
+{
+    public ReactionResult React(GasMixture mixture, IGasMixtureHolder? holder, AtmosphereSystem atmosphereSystem, float heatScale)
+    {
+        var oldHeatCapacity = atmosphereSystem.GetHeatCapacity(mixture, true);
+        var temperature = mixture.Temperature;
+
+        var energyModifier = 1f;
+        var scale = (temperature - Atmospherics.FrezonCoolLowerTemperature) /
+                    (Atmospherics.FrezonCoolMidTemperature - Atmospherics.FrezonCoolLowerTemperature);
+
+        if (scale > 1f)
+        {
+            // Scale energy but not frezon usage if we're in a very, very hot place
+            energyModifier = Math.Min(scale, Atmospherics.FrezonCoolMaximumEnergyModifier);
+            scale = 1f;
+        }
+
+        if (scale <= 0)
+            return ReactionResult.NoReaction;
+
+        var initialNit = mixture.GetMoles(Gas.Nitrogen);
+        var initialFrezon = mixture.GetMoles(Gas.Frezon);
+
+        var burnRate = initialFrezon * scale / Atmospherics.FrezonCoolRateModifier;
+
+        var energyReleased = 0f;
+        if (burnRate > Atmospherics.MinimumHeatCapacity)
+        {
+            var nitAmt = Math.Min(burnRate * Atmospherics.FrezonNitrogenCoolRatio, initialNit);
+            var frezonAmt = Math.Min(burnRate, initialFrezon);
+            mixture.AdjustMoles(Gas.Nitrogen, -nitAmt);
+            mixture.AdjustMoles(Gas.Frezon, -frezonAmt);
+            mixture.AdjustMoles(Gas.NitrousOxide, nitAmt + frezonAmt);
+            energyReleased = burnRate * Atmospherics.FrezonCoolEnergyReleased * energyModifier;
+        }
+
+        energyReleased /= heatScale; // adjust energy to make sure speedup doesn't cause mega temperature rise
+        if (energyReleased >= 0f)
+            return ReactionResult.NoReaction;
+
+        var newHeatCapacity = atmosphereSystem.GetHeatCapacity(mixture, true);
+        if (newHeatCapacity > Atmospherics.MinimumHeatCapacity)
+            mixture.Temperature = (temperature * oldHeatCapacity + energyReleased) / newHeatCapacity;
+
+        return ReactionResult.Reacting;
+    }
+}

Content.Server/Atmos/Reactions/GasReactionPrototype.cs

@@ -25,8 +25,7 @@ public sealed partial class GasReactionPrototype : IPrototype
         public string ID { get; private set; } = default!;
 
         /// <summary>
-        ///     Minimum gas amount requirements. Reactions that meet these minimum mole requirements
-        ///     have their reaction effects run. Generic gas reactions do not have minimum requirements.
+        ///     Minimum gas amount requirements.
         /// </summary>
         [DataField("minimumRequirements")]
         public float[] MinimumRequirements { get; private set; } = new float[Atmospherics.TotalNumberOfGases];
@@ -43,13 +42,6 @@ public sealed partial class GasReactionPrototype : IPrototype
         [DataField("minimumTemperature")]
         public float MinimumTemperatureRequirement { get; private set; } = Atmospherics.TCMB;
 
-        /// <summary>
-        /// If this is a generic gas reaction, multiply the initial rate by this. The default is reasonable for
-        /// synthesis reactions. Consider raising this for fires.
-        /// </summary>
-        [DataField("rateMultiplier")]
-        public float RateMultiplier = 1f;
-
         /// <summary>
         ///     Minimum energy requirement.
         /// </summary>
@@ -68,31 +60,6 @@ public sealed partial class GasReactionPrototype : IPrototype
         /// </summary>
         [DataField("effects")] private List<IGasReactionEffect> _effects = new();
 
-        /// <summary>
-        ///     Energy released by the reaction.
-        /// </summary>
-        [DataField("enthalpy")]
-        public float Enthalpy;
-
-        /// <summary>
-        /// Integer gas IDs and integer ratios required in the reaction. If this is defined, the
-        /// generic gas reaction will run.
-        /// </summary>
-        [DataField("reactants")]
-        public Dictionary<Gas, int> Reactants = new();
-
-        /// <summary>
-        /// Integer gas IDs and integer ratios of reaction products.
-        /// </summary>
-        [DataField("products")]
-        public Dictionary<Gas, int> Products = new();
-
-        /// <summary>
-        /// Integer gas IDs and how much they modify the activation energy (J/mol).
-        /// </summary>
-        [DataField("catalysts")]
-        public Dictionary<Gas, int> Catalysts = new();
-
         /// <summary>
         /// Process all reaction effects.
         /// </summary>

Content.Server/Atmos/Reactions/N2ODecompositionReaction.cs

@@ -0,0 +1,28 @@
+using Content.Server.Atmos.EntitySystems;
+using Content.Shared.Atmos;
+using JetBrains.Annotations;
+
+namespace Content.Server.Atmos.Reactions;
+
+/// <summary>
+///     Decomposes Nitrous Oxide into Nitrogen and Oxygen.
+/// </summary>
+[UsedImplicitly]
+public sealed partial class N2ODecompositionReaction : IGasReactionEffect
+{
+    public ReactionResult React(GasMixture mixture, IGasMixtureHolder? holder, AtmosphereSystem atmosphereSystem, float heatScale)
+    {
+        var cacheN2O = mixture.GetMoles(Gas.NitrousOxide);
+
+        var burnedFuel = cacheN2O / Atmospherics.N2ODecompositionRate;
+
+        if (burnedFuel <= 0 || cacheN2O - burnedFuel < 0)
+            return ReactionResult.NoReaction;
+
+        mixture.AdjustMoles(Gas.NitrousOxide, -burnedFuel);
+        mixture.AdjustMoles(Gas.Nitrogen, burnedFuel);
+        mixture.AdjustMoles(Gas.Oxygen, burnedFuel / 2);
+
+        return ReactionResult.Reacting;
+    }
+}