Implement swimming/gliding including AABB recalculation (#4446)

- The following events have been added:
  - PlayerToggleGlideEvent
  - PlayerToggleSwimEvent
- The following API methods have been added:
  - Entity->getSize()
  - Living->isSwimming()
  - Living->setSwimming()
  - Living->isGliding()
  - Living->setSwimming()
  - Player->toggleSwim()
  - Player->toggleGlide()

src/entity/Entity.php

@@ -304,12 +304,8 @@ abstract class Entity{
 		if($value <= 0){
 			throw new \InvalidArgumentException("Scale must be greater than 0");
 		}
-		$this->size = $this->getInitialSizeInfo()->scale($value);
-
 		$this->scale = $value;
-
-		$this->recalculateBoundingBox();
-		$this->networkPropertiesDirty = true;
+		$this->setSize($this->getInitialSizeInfo()->scale($value));
 	}
 
 	public function getBoundingBox() : AxisAlignedBB{
@@ -329,6 +325,16 @@ abstract class Entity{
 		);
 	}
 
+	public function getSize() : EntitySizeInfo{
+		return $this->size;
+	}
+
+	protected function setSize(EntitySizeInfo $size) : void{
+		$this->size = $size;
+		$this->recalculateBoundingBox();
+		$this->networkPropertiesDirty = true;
+	}
+
 	public function isImmobile() : bool{
 		return $this->immobile;
 	}

src/entity/Living.php

@@ -116,6 +116,10 @@ abstract class Living extends Entity{
 	protected $sprinting = false;
 	/** @var bool */
 	protected $sneaking = false;
+	/** @var bool */
+	protected $gliding = false;
+	/** @var bool */
+	protected $swimming = false;
 
 	abstract public function getName() : string;
 
@@ -227,6 +231,37 @@ abstract class Living extends Entity{
 		}
 	}
 
+	public function isGliding() : bool{
+		return $this->gliding;
+	}
+
+	public function setGliding(bool $value = true) : void{
+		$this->gliding = $value;
+		$this->networkPropertiesDirty = true;
+		$this->recalculateSize();
+	}
+
+	public function isSwimming() : bool{
+		return $this->swimming;
+	}
+
+	public function setSwimming(bool $value = true) : void{
+		$this->swimming = $value;
+		$this->networkPropertiesDirty = true;
+		$this->recalculateSize();
+	}
+
+	private function recalculateSize() : void{
+		$size = $this->getInitialSizeInfo();
+		if($this->isSwimming() || $this->isGliding()){
+			$width = $size->getWidth();
+			//we don't actually know an appropriate eye height for a swimming mob, but 2/3 should be good enough.
+			$this->setSize((new EntitySizeInfo($width, $width, $width * 2 / 3))->scale($this->getScale()));
+		}else{
+			$this->setSize($size->scale($this->getScale()));
+		}
+	}
+
 	public function getMovementSpeed() : float{
 		return $this->moveSpeedAttr->getValue();
 	}
@@ -800,6 +835,8 @@ abstract class Living extends Entity{
 		$properties->setGenericFlag(EntityMetadataFlags::BREATHING, $this->breathing);
 		$properties->setGenericFlag(EntityMetadataFlags::SNEAKING, $this->sneaking);
 		$properties->setGenericFlag(EntityMetadataFlags::SPRINTING, $this->sprinting);
+		$properties->setGenericFlag(EntityMetadataFlags::GLIDING, $this->gliding);
+		$properties->setGenericFlag(EntityMetadataFlags::SWIMMING, $this->swimming);
 	}
 
 	protected function onDispose() : void{

src/event/player/PlayerToggleGlideEvent.php

@@ -0,0 +1,40 @@
+<?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/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\event\player;
+
+use pocketmine\event\Cancellable;
+use pocketmine\event\CancellableTrait;
+use pocketmine\player\Player;
+
+class PlayerToggleGlideEvent extends PlayerEvent implements Cancellable{
+	use CancellableTrait;
+
+	public function __construct(Player $player, protected bool $isGliding){
+		$this->player = $player;
+	}
+
+	public function isGliding() : bool{
+		return $this->isGliding;
+	}
+}

src/event/player/PlayerToggleSwimEvent.php

@@ -0,0 +1,40 @@
+<?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/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\event\player;
+
+use pocketmine\event\Cancellable;
+use pocketmine\event\CancellableTrait;
+use pocketmine\player\Player;
+
+class PlayerToggleSwimEvent extends PlayerEvent implements Cancellable{
+	use CancellableTrait;
+
+	public function __construct(Player $player, protected bool $isSwimming){
+		$this->player = $player;
+	}
+
+	public function isSwimming() : bool{
+		return $this->isSwimming;
+	}
+}

src/network/mcpe/handler/InGamePacketHandler.php

@@ -590,16 +590,28 @@ class InGamePacketHandler extends PacketHandler{
 				}
 				return true;
 			case PlayerAction::START_GLIDE:
+				if(!$this->player->toggleGlide(true)){
+					$this->player->sendData([$this->player]);
+				}
+				return true;
 			case PlayerAction::STOP_GLIDE:
-				break; //TODO
+				if(!$this->player->toggleGlide(false)){
+					$this->player->sendData([$this->player]);
+				}
+				return true;
 			case PlayerAction::CRACK_BREAK:
 				$this->player->continueBreakBlock($pos, $face);
 				break;
 			case PlayerAction::START_SWIMMING:
-				break; //TODO
+				if(!$this->player->toggleSwim(true)){
+					$this->player->sendData([$this->player]);
+				}
+				return true;
 			case PlayerAction::STOP_SWIMMING:
-				//TODO: handle this when it doesn't spam every damn tick (yet another spam bug!!)
-				break;
+				if(!$this->player->toggleSwim(false)){
+					$this->player->sendData([$this->player]);
+				}
+				return true;
 			case PlayerAction::INTERACT_BLOCK: //TODO: ignored (for now)
 				break;
 			case PlayerAction::CREATIVE_PLAYER_DESTROY_BLOCK:

src/player/Player.php

@@ -68,8 +68,10 @@ use pocketmine\event\player\PlayerMoveEvent;
 use pocketmine\event\player\PlayerQuitEvent;
 use pocketmine\event\player\PlayerRespawnEvent;
 use pocketmine\event\player\PlayerToggleFlightEvent;
+use pocketmine\event\player\PlayerToggleGlideEvent;
 use pocketmine\event\player\PlayerToggleSneakEvent;
 use pocketmine\event\player\PlayerToggleSprintEvent;
+use pocketmine\event\player\PlayerToggleSwimEvent;
 use pocketmine\event\player\PlayerTransferEvent;
 use pocketmine\form\Form;
 use pocketmine\form\FormValidationException;
@@ -1768,6 +1770,26 @@ class Player extends Human implements CommandSender, ChunkListener, IPlayer{
 		return true;
 	}
 
+	public function toggleGlide(bool $glide) : bool{
+		$ev = new PlayerToggleGlideEvent($this, $glide);
+		$ev->call();
+		if($ev->isCancelled()){
+			return false;
+		}
+		$this->setGliding($glide);
+		return true;
+	}
+
+	public function toggleSwim(bool $swimming) : bool{
+		$ev = new PlayerToggleSwimEvent($this, $swimming);
+		$ev->call();
+		if($ev->isCancelled()){
+			return false;
+		}
+		$this->setSwimming($swimming);
+		return true;
+	}
+
 	public function emote(string $emoteId) : void{
 		$currentTick = $this->server->getTick();
 		if($currentTick - $this->lastEmoteTick > 5){