Model static fires equalizing with the local atmosphere

Content.Server/Atmos/Components/FlammableComponent.cs

@@ -1,50 +1,58 @@
 using Content.Shared.Alert;
+using Content.Shared.Atmos;
 using Content.Shared.Damage;
 using Robust.Shared.Physics.Collision.Shapes;
 using Robust.Shared.Prototypes;
+using System.Linq;
 
 namespace Content.Server.Atmos.Components
 {
     [RegisterComponent]
     public sealed partial class FlammableComponent : Component
     {
+        // An array which represents the atmos gases as mols, Specifies 1 mol of Oxygen.
+        private static float[] _standardOxygenMols = new float[] { 1f }.Concat(Enumerable.Repeat(0f, Atmospherics.AdjustedNumberOfGases - 1)).ToArray();
+
         [DataField]
         public bool Resisting;
 
-        [ViewVariables(VVAccess.ReadWrite)]
+        /// <summary>
+        /// A gas mix which specifies the minimum mols of each gas needed for the entity to burn. Set to null to burn without atmosphere.
+        /// </summary>
+        [DataField]
+        public GasMixture? FuelGasMix = new GasMixture(_standardOxygenMols, Atmospherics.T20C, 1f);
+
         [DataField]
         public bool OnFire;
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public float FireStacks;
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public float MaximumFireStacks = 10f;
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public float MinimumFireStacks = -10f;
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public string FlammableFixtureID = "flammable";
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public float MinIgnitionTemperature = 373.15f;
 
-        [ViewVariables(VVAccess.ReadWrite)]
+        /// <summary>
+        /// The peak temperature the entity will reach by burning alone.
+        /// </summary>
+        [DataField]
+        public float PeakFlameTemperature = 1500.00f; // vaguely how hot an incenerator gets.
+
         [DataField]
         public bool FireSpread { get; private set; } = false;
 
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public bool CanResistFire { get; private set; } = false;
 
         [DataField(required: true)]
-        [ViewVariables(VVAccess.ReadWrite)]
         public DamageSpecifier Damage = new(); // Empty by default, we don't want any funny NREs.
 
         /// <summary>
@@ -56,31 +64,34 @@ public sealed partial class FlammableComponent : Component
         /// <summary>
         ///     Should the component be set on fire by interactions with isHot entities
         /// </summary>
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public bool AlwaysCombustible = false;
 
         /// <summary>
         ///     Can the component anyhow lose its FireStacks?
         /// </summary>
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public bool CanExtinguish = true;
 
         /// <summary>
         ///     How many firestacks should be applied to component when being set on fire?
         /// </summary>
-        [ViewVariables(VVAccess.ReadWrite)]
         [DataField]
         public float FirestacksOnIgnite = 2.0f;
 
         /// <summary>
         /// Determines how quickly the object will fade out. With positive values, the object will flare up instead of going out.
         /// </summary>
-        [DataField, ViewVariables(VVAccess.ReadWrite)]
+        [DataField]
         public float FirestackFade = -0.1f;
 
         [DataField]
         public ProtoId<AlertPrototype> FireAlert = "Fire";
+
+        /// <summary>
+        /// A maximum quantity of gas to be added to the atmosphere every update while on fire.
+        /// </summary>
+        [DataField]
+        public GasMixture? EmissiveGasMix;
     }
 }

Content.Server/Atmos/EntitySystems/AtmosphereSystem.cs

@@ -107,7 +107,7 @@ public override void Update(float frameTime)
         var query = EntityQueryEnumerator<AtmosExposedComponent, TransformComponent>();
         while (query.MoveNext(out var uid, out _, out var transform))
         {
-            var air = GetContainingMixture((uid, transform));
+            var air = GetContainingMixture((uid, transform), false, true);
 
             if (air == null)
                 continue;

Content.Server/Atmos/EntitySystems/FlammableSystem.cs

@@ -28,6 +28,7 @@
 using Robust.Shared.Physics.Events;
 using Robust.Shared.Physics.Systems;
 using Robust.Shared.Random;
+using Content.Shared.Atmos.Piping.Binary.Components;
 
 namespace Content.Server.Atmos.EntitySystems
 {
@@ -82,6 +83,7 @@ public override void Initialize()
             SubscribeLocalEvent<ExtinguishOnInteractComponent, ActivateInWorldEvent>(OnExtinguishActivateInWorld);
 
             SubscribeLocalEvent<IgniteOnHeatDamageComponent, DamageChangedEvent>(OnDamageChanged);
+
         }
 
         private void OnMeleeHit(EntityUid uid, IgniteOnMeleeHitComponent component, MeleeHitEvent args)
@@ -413,7 +415,6 @@ public override void Update(float frameTime)
 
             _timer -= UpdateTime;
 
-            // TODO: This needs cleanup to take off the crust from TemperatureComponent and shit.
             var query = EntityQueryEnumerator<FlammableComponent, TransformComponent>();
             while (query.MoveNext(out var uid, out var flammable, out _))
             {
@@ -433,20 +434,51 @@ public override void Update(float frameTime)
 
                 if (flammable.FireStacks > 0)
                 {
-                    var air = _atmosphereSystem.GetContainingMixture(uid);
+                    var air = _atmosphereSystem.GetContainingMixture(uid, false, true);
 
-                    // If we're in an oxygenless environment, put the fire out.
-                    if (air == null || air.GetMoles(Gas.Oxygen) < 1f)
+                    if (flammable.FuelGasMix != null)
                     {
-                        Extinguish(uid, flammable);
-                        continue;
+                        // If we're in no atmos extinguish.
+                        if (air == null)
+                        {
+                            Extinguish(uid, flammable);
+                            continue;
+                        }
+
+                        // If our local atmos doesnt have enough of the required gases extinguish.
+                        if (!flammable.FuelGasMix.LEQMoles(air))
+                        {
+                            Extinguish(uid, flammable);
+                            continue;
+                        }
                     }
 
                     var source = EnsureComp<IgnitionSourceComponent>(uid);
                     _ignitionSourceSystem.SetIgnited((uid, source));
 
                     if (TryComp(uid, out TemperatureComponent? temp))
-                        _temperatureSystem.ChangeHeat(uid, 12500 * flammable.FireStacks, false, temp);
+                    {
+                        // get hot
+                        EnsureComp<AtmosExposedComponent>(uid); // required for the entity to ever cool down.
+                        if (!_physicsQuery.TryComp(uid, out var physics))
+                            continue;
+
+                        var maxDeltaT = flammable.PeakFlameTemperature - temp.CurrentTemperature;
+                        if (maxDeltaT > 0) // we dont want to burn and get colder.
+                        {
+
+                            var tempBump = MathF.Sqrt(maxDeltaT * temp.SpecificHeat * physics.Mass) * flammable.FireStacks; //monotonic function, slows as it reaches maxT
+                            _temperatureSystem.ChangeHeat(uid, tempBump, false, temp);
+                        }
+
+                        // release gas
+                        if (air != null && flammable.EmissiveGasMix != null)
+                        {
+                            flammable.EmissiveGasMix.Temperature = air.Temperature;
+                            var releasingGas = flammable.EmissiveGasMix.Clone(); // generate gas for the entity's entire burning lifespan, but we use ReleaseGasTo to handle temperature/pressure for us since those will change for other reasons.
+                            _atmosphereSystem.ReleaseGasTo(releasingGas, air, releasingGas.Pressure); // doing it this way means that we dont need to track the entity damage values or know its destructible or mobstate thresholds.
+                        }                                                                    // the downside, and a possible later rework, is that you ""lose"" some gas if the candle is burning in an atmosphere where it can't emit due to pressure.
+                    }                                                                        // the yml is also slightly cumbersome, because we now specify a "maximum release mix per update (second)" instead of a total gasmix in the entity.
 
                     var ev = new GetFireProtectionEvent();
                     // let the thing on fire handle it

Content.Server/Temperature/Systems/TemperatureSystem.cs

@@ -160,7 +160,8 @@ private void OnAtmosExposedUpdate(EntityUid uid, TemperatureComponent temperatur
         var heatCapacity = GetHeatCapacity(uid, temperature);
         var heat = temperatureDelta * (airHeatCapacity * heatCapacity /
                                        (airHeatCapacity + heatCapacity));
-        ChangeHeat(uid, heat * temperature.AtmosTemperatureTransferEfficiency, temperature: temperature);
+        ChangeHeat(uid, heat * temperature.AtmosTemperatureTransferEfficiency, temperature: temperature); // move heat to entity
+        _atmosphere.AddHeat(args.GasMixture, -1 * heat * temperature.AtmosTemperatureTransferEfficiency); // remove heat from air
     }
 
     public float GetHeatCapacity(EntityUid uid, TemperatureComponent? comp = null, PhysicsComponent? physics = null)

Content.Shared/Atmos/GasMixture.cs

@@ -1,4 +1,4 @@
-using System.Diagnostics.CodeAnalysis;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using Content.Shared.Atmos.EntitySystems;
@@ -271,6 +271,24 @@ public bool Equals(GasMixture? other)
                    && Volume.Equals(other.Volume);
         }
 
+        /// <summary>
+        /// Returns True if supersetMix has more moles for all gases by mole quantity only.
+        /// </summary>
+        /// <param name="supersetMix"></param> 
+        /// <param name="subsetMix"></param>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public bool LEQMoles(GasMixture supersetMix)
+        {
+            for (int i = 0; i < Atmospherics.AdjustedNumberOfGases; i++)
+            {
+                if (supersetMix.GetMoles(i) < GetMoles(i))
+                {
+                    return false;
+                }
+            }
+            return true;
+        }
+
         [SuppressMessage("ReSharper", "NonReadonlyMemberInGetHashCode")]
         public override int GetHashCode()
         {

Resources/Prototypes/Catalog/Cargo/cargo_atmospherics.yml

@@ -111,3 +111,13 @@
 #  cost: 15500
 #  category: cargoproduct-category-name-atmospherics
 #  group: market
+
+- type: cargoProduct
+  id: AtmosphericsCandles
+  icon:
+    sprite: Objects/Misc/candles.rsi
+    state: candle-big
+  product: CrateCandlesAir
+  cost: 2500 # its ~ 32000 mols of Air mix potential. Cheap though because no cannister, and youve got to cool it and collect it to use it.
+  category: cargoproduct-category-name-atmospherics
+  group: market

Resources/Prototypes/Catalog/Fills/Boxes/engineering.yml

@@ -0,0 +1,11 @@
+- type: entity
+  name: air candle box
+  parent: BoxCandle
+  id: BoxCandleAir
+  components:
+  - type: StorageFill
+    contents:
+      - id: CandleGasNitrogen
+        amount: 9
+      - id: CandleGasOxygen
+        amount: 3

Resources/Prototypes/Catalog/Fills/Crates/engineering.yml

@@ -215,3 +215,15 @@
   - type: StorageFill
     contents:
       - id: SpaceHeaterFlatpack
+
+- type: entity
+  id: CrateCandlesAir
+  parent: CrateEngineeringSecure
+  name: air candle crate
+  description: A crate containing 2 boxes of air gas candles.
+  components:
+  - type: StorageFill
+    contents:
+    - id: BoxCandleAir
+      amount: 2
+    - id: BoxFlare

Resources/Prototypes/Entities/Objects/Misc/candles.yml

@@ -32,7 +32,7 @@
       canResistFire: false
       alwaysCombustible: true
       canExtinguish: true
-      firestacksOnIgnite: 3.0
+      firestacksOnIgnite: 3.3
       firestackFade: -0.01
       damage:
         types: