Small Space Wind Optimization Hotfix (#1550)

# Description

I realized only afterwards that there was another place I could have
optimized this, by normalizing the throw vector before we iterate over
every entity on the tile. Which significantly cuts down on what might
otherwise be an internally very complicated step.

# Changelog

No changelog, this isn't player facing, just an optimizing hotfix.

Author: VMSolidus

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

@@ -105,13 +105,18 @@ private void HighPressureMovements(Entity<GridAtmosphereComponent> gridAtmospher
         // Used by ExperiencePressureDifference to correct push/throw directions from tile-relative to physics world.
         var gridWorldRotation = _transformSystem.GetWorldRotation(gridAtmosphere);
 
+        // Atmos Directions only include NSEW cardinals, which means only 4 possible angles to throw at. If Monstermos is enabled, we'll instead do some
+        // Vector shennanigans to smooth it out so that we can throw in increments of up to pi/32.
         var throwDirection = tile.PressureDirection.ToAngle().ToVec();
-        // If we're using monstermos, smooth out the yeet direction to follow the flow
         if (MonstermosEqualization)
             foreach (var nextTile in tile.AdjacentTiles)
                 if (nextTile is not null && nextTile.PressureDirection is not AtmosDirection.Invalid)
                     throwDirection += nextTile.PressureDirection.ToAngle().ToVec();
 
+        // Before you ask, yes I did actually have to convert the angles to vectors, then add them together, then convert the end result back to a normalized vector.
+        // We're normalizing this here and now so that we don't have to normalize it potentially hundreds of times during the next Foreach.
+        var throwVector = (throwDirection.ToAngle() + gridWorldRotation).ToWorldVec().Normalized();
+
         _entSet.Clear();
         _lookup.GetLocalEntitiesIntersecting(tile.GridIndex, tile.GridIndices, _entSet, 0f);
 
@@ -131,8 +136,7 @@ private void HighPressureMovements(Entity<GridAtmosphereComponent> gridAtmospher
                 (entity, EnsureComp<MovedByPressureComponent>(entity)),
                 gridAtmosphere.Comp.UpdateCounter,
                 differentiatedPressure,
-                throwDirection,
-                gridWorldRotation,
+                throwVector,
                 xforms.GetComponent(entity),
                 body);
         }
@@ -154,8 +158,7 @@ public void ExperiencePressureDifference(
         Entity<MovedByPressureComponent> ent,
         int cycle,
         float pressureDifference,
-        Vector2 direction,
-        Angle gridWorldRotation,
+        Vector2 throwVector,
         TransformComponent? xform = null,
         PhysicsComponent? physics = null)
     {
@@ -171,11 +174,9 @@ public void ExperiencePressureDifference(
         if (pressureDifference < physics.Mass)
             return;
 
-        // Grid-rotation adjusted direction
-        var dirVec = (direction.ToAngle() + gridWorldRotation).ToWorldVec();
         pressureDifference *= MathF.Max(physics.InvMass, SpaceWindMaximumCalculatedInverseMass);
 
-        _throwing.TryThrow(uid, dirVec.Normalized() * MathF.Min(pressureDifference, SpaceWindMaxVelocity), pressureDifference);
+        _throwing.TryThrow(uid, throwVector * MathF.Min(pressureDifference, SpaceWindMaxVelocity), pressureDifference);
         component.LastHighPressureMovementAirCycle = cycle;
     }
 }