From 3be560512627b1c7f5a11d4d754d1bb3c673e45c Mon Sep 17 00:00:00 2001
From: Geolykt <admin@geolykt.de>
Date: Wed, 4 Nov 2020 20:31:29 +0100
Subject: [PATCH] Added distanceSquared where applicable

Warning: Also breaks current API-Implementation (API-specification remains the same) in a way that BlockPosition#getDistance(BlockPosition) no longer returns the manhattan distance, but the distance according to pythagoras.
---
 .../minestom/server/utils/BlockPosition.java  | 28 +++++++++++++++++--
 .../net/minestom/server/utils/Position.java   | 14 ++++++++++
 .../net/minestom/server/utils/Vector.java     | 10 +++++++
 3 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/src/main/java/net/minestom/server/utils/BlockPosition.java b/src/main/java/net/minestom/server/utils/BlockPosition.java
index b597012d8..3e819dadb 100644
--- a/src/main/java/net/minestom/server/utils/BlockPosition.java
+++ b/src/main/java/net/minestom/server/utils/BlockPosition.java
@@ -174,17 +174,41 @@ public class BlockPosition {
     }
 
     /**
-     * Gets the distance to another block position.
+     * Gets the manhattan distance to another block position.
      *
      * @param blockPosition the block position to check the distance
      * @return the distance between 'this' and {@code blockPosition}
      */
-    public int getDistance(@NotNull BlockPosition blockPosition) {
+    public int getManhattanDistance(@NotNull BlockPosition blockPosition) {
         return Math.abs(getX() - blockPosition.getX()) +
                 Math.abs(getY() - blockPosition.getY()) +
                 Math.abs(getZ() - blockPosition.getZ());
     }
 
+    /**
+     * Gets the distance to another block position.
+     * In cases where performance matters, {@link #getDistanceSquared(BlockPosition)} should be used
+     * as it does not perform the expensive Math.sqrt method.
+     *
+     * @param blockPosition the block position to check the distance
+     * @return the distance between 'this' and {@code blockPosition}
+     */
+    public double getDistance(@NotNull BlockPosition blockPosition) {
+        return Math.sqrt(getDistanceSquared(blockPosition));
+    }
+
+    /**
+     * Gets the square distance to another block position.
+    *
+    * @param blockPosition the block position to check the distance
+    * @return the distance between 'this' and {@code blockPosition}
+    */
+   public int getDistanceSquared(@NotNull BlockPosition blockPosition) {
+       return MathUtils.square(getX() - blockPosition.getX()) +
+               MathUtils.square(getY() - blockPosition.getY()) +
+               MathUtils.square(getZ() - blockPosition.getZ());
+   }
+
     /**
      * Copies this block position.
      *
diff --git a/src/main/java/net/minestom/server/utils/Position.java b/src/main/java/net/minestom/server/utils/Position.java
index c587384a3..66b1d9978 100644
--- a/src/main/java/net/minestom/server/utils/Position.java
+++ b/src/main/java/net/minestom/server/utils/Position.java
@@ -72,6 +72,8 @@ public class Position {
 
     /**
      * Gets the distance between 2 positions.
+     *   In cases where performance matters, {@link #getDistanceSquared(Position)} should be used
+     *   as it does not perform the expensive Math.sqrt method.
      *
      * @param position the second position
      * @return the distance between {@code this} and {@code position}
@@ -82,6 +84,18 @@ public class Position {
                 MathUtils.square(position.getZ() - getZ()));
     }
 
+    /**
+     * Gets the square distance to another position.
+    *
+    * @param position the second position
+    * @return the squared distance between {@code this} and {@code position}
+    */
+   public float getDistanceSquared(Position position) {
+       return MathUtils.square(getX() - position.getX()) +
+               MathUtils.square(getY() - position.getY()) +
+               MathUtils.square(getZ() - position.getZ());
+   }
+
     /**
      * Gets a unit-vector pointing in the direction that this Location is
      * facing.
diff --git a/src/main/java/net/minestom/server/utils/Vector.java b/src/main/java/net/minestom/server/utils/Vector.java
index e4542a379..f88382a8f 100644
--- a/src/main/java/net/minestom/server/utils/Vector.java
+++ b/src/main/java/net/minestom/server/utils/Vector.java
@@ -118,6 +118,16 @@ public class Vector {
         return Math.sqrt(MathUtils.square(x - o.x) + MathUtils.square(y - o.y) + MathUtils.square(z - o.z));
     }
 
+    /**
+     * Gets the squared distance between this vector and another.
+     *
+     * @param o The other vector
+     * @return the squared distance
+     */
+    public double distanceSquared(Vector o) {
+        return MathUtils.square(x - o.x) + MathUtils.square(y - o.y) + MathUtils.square(z - o.z);
+    }
+
     /**
      * Performs scalar multiplication, multiplying all components with a
      * scalar.