Improve performance of updating entity radiation (especially when the…

…re is no radiation sources in the world)

src/main/java/mekanism/common/lib/radiation/RadiationManager.java

@@ -152,6 +152,9 @@ public ResourceKey<DamageType> getRadiationDamageTypeKey() {
 
     @Override
     public double getRadiationLevel(Entity entity) {
+        if (radiationTable.isEmpty()) {//Short circuit when the radiation table is empty
+            return BASELINE;
+        }
         return getRadiationLevel(GlobalPos.of(entity.level().dimension(), entity.blockPosition()));
     }
 
@@ -199,24 +202,49 @@ public void removeRadiationSource(GlobalPos pos) {
 
     @Override
     public double getRadiationLevel(GlobalPos pos) {
+        if (radiationTable.isEmpty()) {//Short circuit when the radiation table is empty
+            return BASELINE;
+        }
         return getRadiationLevelAndMaxMagnitude(pos).level();
     }
 
     public LevelAndMaxMagnitude getRadiationLevelAndMaxMagnitude(Entity entity) {
+        if (radiationTable.isEmpty()) {//Short circuit when the radiation table is empty
+            return LevelAndMaxMagnitude.BASELINE;
+        }
         return getRadiationLevelAndMaxMagnitude(GlobalPos.of(entity.level().dimension(), entity.blockPosition()));
     }
 
     public LevelAndMaxMagnitude getRadiationLevelAndMaxMagnitude(GlobalPos pos) {
+        if (radiationTable.isEmpty()) {//Short circuit when the radiation table is empty
+            return LevelAndMaxMagnitude.BASELINE;
+        }
         double level = BASELINE;
         double maxMagnitude = BASELINE;
+        Chunk3D center = new Chunk3D(pos);
+        int radius = MekanismConfig.general.radiationChunkCheckRadius.get();
         // we only compute exposure when within the MAX_RANGE bounds
-        double maxRange = Mth.square(MekanismConfig.general.radiationChunkCheckRadius.get() * 16);
-        for (Chunk3D chunk : new Chunk3D(pos).expand(MekanismConfig.general.radiationChunkCheckRadius.get())) {
-            for (Map.Entry<GlobalPos, RadiationSource> entry : radiationTable.row(chunk).entrySet()) {
-                if (entry.getKey().pos().distSqr(pos.pos()) <= maxRange) {
-                    RadiationSource source = entry.getValue();
-                    level += computeExposure(pos, source);
-                    maxMagnitude = Math.max(maxMagnitude, source.getMagnitude());
+        double maxRange = Mth.square(radius * 16);
+        int minX, maxX, minZ, maxZ;
+        if (radius == 1) {
+            maxX = minX = center.x;
+            maxZ = minZ = center.z;
+        } else {
+            minX = center.x - radius;
+            minZ = center.z - radius;
+            maxX = center.x + radius;
+            maxZ = center.z + radius;
+        }
+        //Note: We inline the logic from Chunk3D#expand to avoid allocating a new hash set each time
+        for (int i = minX; i <= maxX; i++) {
+            for (int j = minZ; j <= maxZ; j++) {
+                Chunk3D chunk = new Chunk3D(center.dimension, i, j);
+                for (Map.Entry<GlobalPos, RadiationSource> entry : radiationTable.row(chunk).entrySet()) {
+                    if (entry.getKey().pos().distSqr(pos.pos()) <= maxRange) {
+                        RadiationSource source = entry.getValue();
+                        level += computeExposure(pos, source);
+                        maxMagnitude = Math.max(maxMagnitude, source.getMagnitude());
+                    }
                 }
             }
         }
@@ -496,6 +524,8 @@ public void onLivingTick(LivingTickEvent event) {
     }
 
     public record LevelAndMaxMagnitude(double level, double maxMagnitude) {
+
+        private static final LevelAndMaxMagnitude BASELINE = new LevelAndMaxMagnitude(RadiationManager.BASELINE, RadiationManager.BASELINE);
     }
 
     public enum RadiationScale {

src/main/java/mekanism/common/lib/radiation/capability/RadiationEntity.java

@@ -41,10 +41,13 @@ public void update() {
         if (!entity.isAlive() || entity instanceof Player player && !MekanismUtils.isPlayingMode(player)) {
             return;
         }
-        entity.getData(MekanismAttachmentTypes.RADIATION);
+        double radiation = getRadiation();
+        if (radiation <= RadiationManager.BASELINE) {
+            //NO-OP, the entity isn't actually irradiated
+            return;
+        }
 
         RandomSource rand = entity.level().getRandom();
-        double radiation = getRadiation();
         double minSeverity = MekanismConfig.general.radiationNegativeEffectsMinSeverity.get();
         double severityScale = RadiationScale.getScaledDoseSeverity(radiation);
         double chance = minSeverity + rand.nextDouble() * (1 - minSeverity);