make ticked explosions less laggy

common/src/main/java/common/entity/item/EntityExplosion.java

@@ -3,6 +3,7 @@ package common.entity.item;
 import common.entity.Entity;
 import common.entity.EntityType;
 import common.tags.TagObject;
+import common.vars.Vars;
 import common.world.Explosion;
 import common.world.World;
 
@@ -10,13 +11,13 @@ public class EntityExplosion extends Entity
 {
     private int progress;
     private int radius;
+    private int iteration;
 
     public EntityExplosion(World worldIn)
     {
         super(worldIn);
         this.preventSpawning = true;
         this.setSize(0.1F, 0.1F);
-//		this.setInvisible(true);
     }
     
     public EntityExplosion(World worldIn, double x, double y, double z)
@@ -49,29 +50,34 @@ public class EntityExplosion extends Entity
         this.prevY = this.posY;
         this.prevZ = this.posZ;
         this.motionX = this.motionY = this.motionZ = 0.0D;
-    	if(this.progress++ >= this.radius) {
+        if(this.worldObj.client)
+        	return;
+    	if(this.progress >= this.radius) {
     		this.setDead();
+    		return;
     	}
-    	else if(!this.worldObj.client) {
-            this.explode(this.progress - 1);
-        }
+        if(this.explode(this.progress - 1))
+        	++this.progress;
     }
 
-    private void explode(double min)
+    private boolean explode(double min)
     {
-		Explosion.doExplosionAlgo3(this.worldObj, this.posX, this.posY + (double)(this.height / 2.0F), this.posZ, this.rand, min + 6.0d, min);
+		this.iteration = Explosion.doExplosionAlgo3(this.worldObj, this.posX, this.posY, this.posZ, this.rand, min + 6.0d, min, this.iteration, Vars.maxExplosionIters);
+		return this.iteration == 0;
     }
     
     protected void writeEntity(TagObject tagCompound)
     {
         tagCompound.setInt("Progress", this.progress);
         tagCompound.setInt("Radius", this.radius);
+        tagCompound.setInt("Iteration", this.iteration);
     }
     
     protected void readEntity(TagObject tagCompund)
     {
         this.progress = tagCompund.getInt("Progress");
         this.radius = tagCompund.getInt("Radius");
+        this.iteration = tagCompund.getInt("Iteration");
     }
 
     public float getEyeHeight()

common/src/main/java/common/vars/Vars.java

@@ -253,6 +253,8 @@ public abstract class Vars {
 	public static int eggTimer = 6000;
 	@Var(name = "spawnMoreZombies")
 	public static int spawnMoreZombie = 25;
+	@Var(name = "explosionBlocksPerTick", min = 100, max = 100000)
+	public static int maxExplosionIters = 1024;
 
 	@Var(name = "knockback")
 	public static float knockback = 1.0f;

common/src/main/java/common/world/Explosion.java

@@ -26,6 +26,32 @@ import common.vars.Vars;
 
 public class Explosion
 {
+	private static final int[][] TABLES = new int[1024][];
+	
+	private static int[] shuffle(int size) {
+		int[] table = new int[size];
+		Random rand = new Random(8236737136521L);
+		for(int z = 0; z < size; z++) {
+			table[z] = z;
+		}
+		for(int z = 0; z < size; z++) {
+			int r = rand.zrange(size);
+			int n = table[z];
+			table[z] = table[r];
+			table[r] = n;
+		}
+		return table;
+	}
+	
+	private static int[] getTable(int size) {
+		if(size < 0 || size >= TABLES.length)
+			return null;
+		int[] table = TABLES[size];
+		if(table == null)
+			TABLES[size] = table = shuffle(size);
+		return table;
+	}
+	
     /** whether or not the explosion sets fire to blocks around it */
     private final boolean isFlaming;
 
@@ -151,17 +177,22 @@ public class Explosion
         }
     }
     
-    public static void doExplosionAlgo3(World worldObj, double explosionX, double explosionY, double explosionZ, Random rand, double explosionSize, double minDist)
+    public static int doExplosionAlgo3(World worldObj, double explosionX, double explosionY, double explosionZ, Random rand, double explosionSize, double minDist, int iter, int max)
     {
     	int d = ((int)explosionSize) + 1;
+    	int div = d * 2 + 1;
+    	int[] table = getTable(div);
+    	if(table == null)
+    		return 0;
     	double falloff = explosionSize * 0.125d;
     	falloff = falloff > 4.0d ? 4.0d : falloff;
-        for (int x = -d; x <= d; ++x)
-        {
-            for (int y = -d; y <= d; ++y)
-            {
-                for (int z = -d; z <= d; ++z)
+    	int lmt = div * div * div;
+    	int cnt = 0;
+        for(; iter < lmt && cnt < max; iter++)
         {
+        	int x = table[(iter / div) % div] - d;
+        	int y = table[iter % div] - d;
+        	int z = table[(iter / div) / div] - d;
         	double dist = (double)ExtMath.sqrtd(((double)x) * ((double)x) + ((double)y) * ((double)y) + ((double)z) * ((double)z));
         	if(dist > minDist && (dist < explosionSize - falloff || 
         			(dist < explosionSize && rand.doublev() + ((dist - (explosionSize - falloff)) / falloff) < 1.0d))) {
@@ -174,8 +205,7 @@ public class Explosion
                 		((AWorldServer)worldObj).spawnParticle(ParticleType.EXPLOSION_HUGE, explosionX + x, explosionY + y, explosionZ + z, 0, rand.gaussian() * 0.02D, rand.gaussian() * 0.02D, rand.gaussian() * 0.02D, 1.0, 0);
                 	}
                 }
-                	}
-                }
+                cnt++;
         	}
         }
         
@@ -195,6 +225,8 @@ public class Explosion
 	            }
 	        }
         }
+        
+        return iter >= lmt ? 0 : iter;
     }
 
     /**