added explosion effect

src/main/java/de/ellpeck/naturesaura/ModConfig.java

@@ -38,6 +38,8 @@ public final class ModConfig {
         public boolean grassDieEffect = true;
         @Comment("If the Aura Imbalance effect of plant growth being boosted if the Aura levels are high enough should occur")
         public boolean plantBoostEffect = true;
+        @Comment("If the Aura Imbalance effect of explosions happening randomly if Aura levels are too low should occur")
+        public boolean explosionEffect = true;
     }
 
     public static class Client {

src/main/java/de/ellpeck/naturesaura/chunk/effect/DrainSpotEffects.java

@@ -9,5 +9,6 @@ public final class DrainSpotEffects {
         NaturesAuraAPI.DRAIN_SPOT_EFFECTS.put(PlantBoostEffect.NAME, PlantBoostEffect::new);
         NaturesAuraAPI.DRAIN_SPOT_EFFECTS.put(ReplenishingEffect.NAME, ReplenishingEffect::new);
         NaturesAuraAPI.DRAIN_SPOT_EFFECTS.put(BalanceEffect.NAME, BalanceEffect::new);
+        NaturesAuraAPI.DRAIN_SPOT_EFFECTS.put(ExplosionEffect.NAME, ExplosionEffect::new);
     }
 }

src/main/java/de/ellpeck/naturesaura/chunk/effect/ExplosionEffect.java

@@ -0,0 +1,53 @@
+package de.ellpeck.naturesaura.chunk.effect;
+
+import de.ellpeck.naturesaura.ModConfig;
+import de.ellpeck.naturesaura.NaturesAura;
+import de.ellpeck.naturesaura.api.aura.chunk.IAuraChunk;
+import de.ellpeck.naturesaura.api.aura.chunk.IDrainSpotEffect;
+import de.ellpeck.naturesaura.api.aura.type.IAuraType;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.MathHelper;
+import net.minecraft.world.World;
+import net.minecraft.world.chunk.Chunk;
+import org.apache.commons.lang3.mutable.MutableInt;
+
+public class ExplosionEffect implements IDrainSpotEffect {
+
+    public static final ResourceLocation NAME = new ResourceLocation(NaturesAura.MOD_ID, "explosions");
+
+    @Override
+    public void update(World world, Chunk chunk, IAuraChunk auraChunk, BlockPos pos, MutableInt spot) {
+        if (spot.intValue() >= 0 || world.getTotalWorldTime() % 40 != 0)
+            return;
+        int aura = IAuraChunk.getAuraInArea(world, pos, 85);
+        if (aura > -50000)
+            return;
+        int chance = 140 - Math.abs(aura) / 2000;
+        if (chance > 1 && world.rand.nextInt(chance) != 0)
+            return;
+        float strength = Math.min(Math.abs(aura) / 50000F, 5F);
+        if (strength <= 0)
+            return;
+        int dist = MathHelper.clamp(Math.abs(aura) / 2000, 25, 100);
+
+        int x = MathHelper.floor(pos.getX() + world.rand.nextGaussian() * dist);
+        int z = MathHelper.floor(pos.getZ() + world.rand.nextGaussian() * dist);
+        BlockPos chosenPos = new BlockPos(x, world.getHeight(x, z), z);
+        if (chosenPos.distanceSq(pos) <= dist * dist && world.isBlockLoaded(chosenPos)) {
+            world.newExplosion(null,
+                    chosenPos.getX() + 0.5, chosenPos.getY() + 0.5, chosenPos.getZ() + 0.5,
+                    strength, false, true);
+        }
+    }
+
+    @Override
+    public boolean appliesHere(Chunk chunk, IAuraChunk auraChunk, IAuraType type) {
+        return ModConfig.enabledFeatures.explosionEffect;
+    }
+
+    @Override
+    public ResourceLocation getName() {
+        return NAME;
+    }
+}

src/main/java/de/ellpeck/naturesaura/chunk/effect/GrassDieEffect.java

@@ -29,7 +29,6 @@ public class GrassDieEffect implements IDrainSpotEffect {
                 int amount = Math.min(300, Math.abs(aura) / 1000);
                 if (amount > 1) {
                     int dist = MathHelper.clamp(Math.abs(aura) / 750, 5, 45);
-                    if (dist > 0) {
                     for (int i = amount / 2 + world.rand.nextInt(amount / 2); i >= 0; i--) {
                         BlockPos grassPos = new BlockPos(
                                 pos.getX() + world.rand.nextGaussian() * dist,
@@ -56,7 +55,6 @@ public class GrassDieEffect implements IDrainSpotEffect {
             }
         }
     }
-    }
 
     @Override
     public boolean appliesHere(Chunk chunk, IAuraChunk auraChunk, IAuraType type) {

src/main/java/de/ellpeck/naturesaura/chunk/effect/PlantBoostEffect.java

@@ -34,8 +34,6 @@ public class PlantBoostEffect implements IDrainSpotEffect {
         if (amount <= 1)
             return;
         int dist = MathHelper.clamp(Math.abs(aura) / 1500, 5, 35);
-        if (dist <= 0)
-            return;
 
         for (int i = amount / 2 + world.rand.nextInt(amount / 2); i >= 0; i--) {
             int x = MathHelper.floor(pos.getX() + world.rand.nextGaussian() * dist);

src/main/resources/assets/naturesaura/patchouli_books/book/en_us/entries/effects/explosions.json

@@ -0,0 +1,12 @@
+{
+    "name": "Unstable Outbreak",
+    "icon": "minecraft:tnt",
+    "category": "effects",
+    "advancement": "naturesaura:furnace_heater",
+    "pages": [
+        {
+            "type": "text",
+            "text": "When the $(aura) levels in the area are extremely low, to the point that $(item)Natural Decay$() has already done all of the work it can, but the levels are still not increased, nature itself loses stability to the point of $(item)Unstable Outbreak$(): $(thing)Explosions$() will start sporadically occuring in a large area on the surface, their severity and interval varying based on the severity of the imbalance."
+        }
+    ]
+}