diff --git a/src/Entity.php b/src/Entity.php
index 2f0322135..baeae4966 100644
--- a/src/Entity.php
+++ b/src/Entity.php
@@ -20,7 +20,9 @@
 */
 
 abstract class Entity extends Position{
-	private static $entityCount = 1;
+	public static $entityCount = 1;
+	public static $list = array();
+	public static $needUpdate = array();
 	private $id;
 	
 	//public $passenger = null;
@@ -34,7 +36,7 @@ abstract class Entity extends Position{
 	public $pitch;
 	public $lastYaw;
 	public $lastPitch;
-	//public $boundingBox;
+	public $boundingBox;
 	public $onGround;
 	public $positionChanged;
 	public $velocityChanged;
@@ -52,17 +54,29 @@ abstract class Entity extends Position{
 	protected $fireProof;
 	private $invulnerable;
 	
+	public static function getEntity($entityID){
+		return isset(Entity::$list[$entityID]) ? Entity::$list[$entityID]:false;
+	}
+	
 	
 	public function __construct(Level $level){
 		$this->id = Entity::$entityCount++;
 		$this->justCreated = true;
 		$this->level = $level;
+		$this->setPosition(new Vector3(0, 0, 0));
+		Entity::$list[$this->id] = $this;
 	}
 	
 	public function getPosition(){
 		return new Position($this->x, $this->y, $this->z, $this->level);
 	}
 	
+	public function setPosition(Vector3 $pos){
+		$this->x = $pos->x;
+		$this->y = $pos->y;
+		$this->z = $pos->z;
+	}
+	
 	public function setVelocity(Vector3 $velocity){
 		$this->velocity = clone $velocity;
 	}
diff --git a/src/math/AxisAlignedBB.php b/src/math/AxisAlignedBB.php
new file mode 100644
index 000000000..2db5a362f
--- /dev/null
+++ b/src/math/AxisAlignedBB.php
@@ -0,0 +1,206 @@
+<?php
+
+/**
+ *
+ *  ____            _        _   __  __ _                  __  __ ____  
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \ 
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/ 
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_| 
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ * 
+ *
+*/
+
+class AxisAlignedBB{
+	public $minX;
+	public $minY;
+	public $minZ;
+	public $maxX;
+	public $maxY;
+	public $maxZ;
+
+	public function __construct($minX, $minY, $minZ, $maxX, $maxY, $maxZ){
+		$this->minX = $minX;
+		$this->minY = $minY;
+		$this->minZ = $minZ;
+		$this->maxX = $maxX;
+		$this->maxY = $maxY;
+		$this->maxZ = $maxZ;
+	}
+
+	public function setBounds($minX, $minY, $minZ, $maxX, $maxY, $maxZ){
+		$this->minX = $minX;
+		$this->minY = $minY;
+		$this->minZ = $minZ;
+		$this->maxX = $maxX;
+		$this->maxY = $maxY;
+		$this->maxZ = $maxZ;
+	}
+	
+	public function addCoord($x, $y, $z){
+		if($x < 0){
+			$this->minX += $x;
+		}elseif($x > 0){
+			$this->maxX += $x;
+		}
+
+		if($y < 0){
+			$this->minY += $y;
+		}elseif($y > 0){
+			$this->maxY += $y;
+		}
+
+		if($z < 0){
+			$this->minZ += $z;
+		}elseif($z > 0){
+			$this->maxZ += $z;
+		}
+	}
+	
+	public function expand($x, $y, $z){
+		$this->minX -= $x;
+		$this->minY -= $y;
+		$this->minZ -= $z;
+		$this->maxX += $x;
+		$this->maxY += $y;
+		$this->maxZ += $z;
+	}
+
+	public function offset($x, $y, $z){
+		$this->minX += $x;
+		$this->minY += $y;
+		$this->minZ += $z;
+		$this->maxX += $x;
+		$this->maxY += $y;
+		$this->maxZ += $z;
+	}
+	
+	public function contract($x, $y, $z){
+		$this->minX += $x;
+		$this->minY += $y;
+		$this->minZ += $z;
+		$this->maxX -= $x;
+		$this->maxY -= $y;
+		$this->maxZ -= $z;
+	}
+	
+	public function getOffsetBoundingBox($x, $y, $z){
+		return new AxisAlignedBB($this->minX + $x, $this->minY + $y, $this->minZ + $z, $this->maxX + $x, $this->maxY + $y, $this->maxZ + $z);
+	}
+	
+	public function calculateXOffset(AxisAlignedBB $bb, $x){
+		if($bb->maxY <= $this->minY or $bb->minY >= $this->maxY){
+			return $x;
+		}
+		if($bb->maxZ <= $this->minZ or $bb->minZ >= $this->maxZ){
+			return $x;
+		}
+		if($x > 0 and $bb->maxX <= $this->minX){
+			$x1 = $this->minX - $bb->maxX;
+			if($x1 < $x){
+				$x = $x1;
+			}
+		}
+		if($x < 0 and $bb->minX >= $this->maxX){
+			$x2 = $this->maxX - $bb->minX;
+			if($x2 > $x){
+				$x = $x2;
+			}
+		}
+		return $x;
+	}
+	
+	public function calculateYOffset(AxisAlignedBB $bb, $y){
+		if($bb->maxX <= $this->minX or $bb->minX >= $this->maxX){
+			return $y;
+		}
+		if($bb->maxZ <= $this->minZ or $bb->minZ >= $this->maxZ){
+			return $y;
+		}
+		if($y > 0 and $bb->maxY <= $this->minY){
+			$y1 = $this->minY - $bb->maxY;
+			if($y1 < $y){
+				$y = $y1;
+			}
+		}
+		if($y < 0 and $bb->minY >= $this->maxY){
+			$y2 = $this->maxY - $bb->minY;
+			if($y2 > $y){
+				$y = $y2;
+			}
+		}
+		return $y;
+	}
+	
+	public function calculateZOffset(AxisAlignedBB $bb, $z){
+		if($bb->maxX <= $this->minX or $bb->minX >= $this->maxX){
+			return $z;
+		}
+		if($bb->maxY <= $this->minY or $bb->minY >= $this->maxY){
+			return $z;
+		}
+		if($z > 0 and $bb->maxZ <= $this->minZ){
+			$z1 = $this->minZ - $bb->maxZ;
+			if($z1 < $z){
+				$z = $z1;
+			}
+		}
+		if($z < 0 and $bb->minZ >= $this->maxZ){
+			$z2 = $this->maxZ - $bb->minZ;
+			if($z2 > $z){
+				$z = $z2;
+			}
+		}
+		return $z;
+	}
+	
+	public function intersectsWith(AxisAlignedBB $bb){
+		if($bb->maxX <= $this->minX or $bb->minX >= $this->maxX){
+			return false;
+		}
+		if($bb->maxY <= $this->minY or $bb->minY >= $this->maxY){
+			return false;
+		}
+		return $bb->maxZ > $this->minZ and $bb->minZ < $this->maxZ;
+	}
+	
+	public function isVectorInside(Vector3 $vector){
+		if($vector->x <= $this->minX or $vector->x >= $this->maxX){
+			return false;
+		}
+		if($vector->y <= $this->minY or $vector->y >= $this->maxY){
+			return false;
+		}
+		return $vector->z > $this->minZ and $vector->z < $this->maxZ;
+	}
+	
+	public function getAverageEdgeLength(){
+		return ($this->maxX - $this->minX + $this->maxY - $this->minY + $this->maxZ - $this->minZ) / 3; 
+	}
+	
+	public function isVectorInYZ(Vector3 $vector){
+		return $vector->y >= $this->minY and $vector->y <= $this->maxY and $vector->z >= $this->minZ and $vector->z <= $this->maxZ;
+	}
+	
+	public function isVectorInXZ(Vector3 $vector){
+		return $vector->x >= $this->minX and $vector->x <= $this->maxX and $vector->z >= $this->minZ and $vector->z <= $this->maxZ;
+	}
+	
+	public function isVectorInXY(Vector3 $vector){
+		return $vector->x >= $this->minX and $vector->x <= $this->maxX and $vector->y >= $this->minY and $vector->y <= $this->maxY;
+	}
+	
+	/*
+	public function calculateIntercept(...){
+	
+	}
+	*/
+}
\ No newline at end of file