[Bleeding] Optimized locToBlock. Addresses BUKKIT-815

By: Wesley Wolfe <weswolf@aol.com>

paper-api/src/main/java/org/bukkit/Location.java

@@ -1,6 +1,7 @@
 package org.bukkit;
 
 import org.bukkit.block.Block;
+import org.bukkit.util.NumberConversions;
 import org.bukkit.util.Vector;
 
 /**
@@ -485,6 +486,6 @@ public class Location implements Cloneable {
      * @return Block coordinate
      */
     public static int locToBlock(double loc) {
-        return (int) Math.floor(loc);
+        return NumberConversions.floor(loc);
     }
 }

paper-api/src/main/java/org/bukkit/util/BlockIterator.java

@@ -1,5 +1,7 @@
 package org.bukkit.util;
 
+import static org.bukkit.util.NumberConversions.*;
+
 import org.bukkit.World;
 import org.bukkit.Location;
 import org.bukkit.block.Block;
@@ -66,7 +68,7 @@ public class BlockIterator implements Iterator<Block> {
         double secondPosition = 0;
         double thirdPosition = 0;
 
-        Block startBlock = this.world.getBlockAt((int) Math.floor(startClone.getX()), (int) Math.floor(startClone.getY()), (int) Math.floor(startClone.getZ()));
+        Block startBlock = this.world.getBlockAt(floor(startClone.getX()), floor(startClone.getY()), floor(startClone.getZ()));
 
         if (getXLength(direction) > mainDirection) {
             mainFace = getXFace(direction);
@@ -117,10 +119,10 @@ public class BlockIterator implements Iterator<Block> {
         // Guarantee that the ray will pass though the start block.
         // It is possible that it would miss due to rounding
         // This should only move the ray by 1 grid position
-        secondError = (int) (Math.floor(secondd * gridSize));
-        secondStep = (int) (Math.round(secondDirection / mainDirection * gridSize));
-        thirdError = (int) (Math.floor(thirdd * gridSize));
-        thirdStep = (int) (Math.round(thirdDirection / mainDirection * gridSize));
+        secondError = floor(secondd * gridSize);
+        secondStep = round(secondDirection / mainDirection * gridSize);
+        thirdError = floor(thirdd * gridSize);
+        thirdStep = round(thirdDirection / mainDirection * gridSize);
 
         if (secondError + secondStep <= 0) {
             secondError = -secondStep + 1;
@@ -168,7 +170,7 @@ public class BlockIterator implements Iterator<Block> {
         }
 
         // Calculate the number of planes passed to give max distance
-        maxDistanceInt = (int) Math.round(maxDistance / (Math.sqrt(mainDirection * mainDirection + secondDirection * secondDirection + thirdDirection * thirdDirection) / mainDirection));
+        maxDistanceInt = round(maxDistance / (Math.sqrt(mainDirection * mainDirection + secondDirection * secondDirection + thirdDirection * thirdDirection) / mainDirection));
 
     }
 

paper-api/src/main/java/org/bukkit/util/NumberConversions.java

@@ -6,6 +6,15 @@ package org.bukkit.util;
 public final class NumberConversions {
     private NumberConversions() {}
 
+    public static int floor(double num) {
+        final int floor = (int) num;
+        return floor == num ? floor : floor - (int) (Double.doubleToRawLongBits(num) >>> 63);
+    }
+
+    public static int round(double num) {
+        return floor(num + 0.5d);
+    }
+
     public static int toInt(Object object) {
         if (object instanceof Number) {
             return ((Number) object).intValue();

paper-api/src/main/java/org/bukkit/util/Vector.java

@@ -365,7 +365,7 @@ public class Vector implements Cloneable, ConfigurationSerializable {
      * @return block X
      */
     public int getBlockX() {
-        return (int) Math.floor(x);
+        return NumberConversions.floor(x);
     }
 
     /**
@@ -384,7 +384,7 @@ public class Vector implements Cloneable, ConfigurationSerializable {
      * @return block y
      */
     public int getBlockY() {
-        return (int) Math.floor(y);
+        return NumberConversions.floor(y);
     }
 
     /**
@@ -403,7 +403,7 @@ public class Vector implements Cloneable, ConfigurationSerializable {
      * @return block z
      */
     public int getBlockZ() {
-        return (int) Math.floor(z);
+        return NumberConversions.floor(z);
     }
 
     /**