Added WorldBorder#isInside + physics now support world border

src/main/java/net/minestom/server/collision/CollisionUtils.java

@@ -15,6 +15,7 @@ public class CollisionUtils {
 
     /**
      * Moves an entity with physics applied (ie checking against blocks)
+     *
      * @param entity      the entity to move
      * @param positionOut the Position object in which the new position will be saved
      * @param velocityOut the Vector object in which the new velocity will be saved
@@ -61,6 +62,7 @@ public class CollisionUtils {
     /**
      * Steps on a single axis. Checks against collisions for each point of 'corners'. This method assumes that startPosition is valid.
      * Immediately return false if corners is of length 0.
+     *
      * @param instance      instance to check blocks from
      * @param startPosition starting position for stepping, can be intermediary position from last step
      * @param axis          step direction. Works best if unit vector and aligned to an axis
@@ -119,6 +121,7 @@ public class CollisionUtils {
 
     /**
      * Steps once (by a length of 1 block) on the given axis. Returns false if this method encountered a collision
+     *
      * @param instance        instance to get blocks from
      * @param axis            the axis to move along
      * @param cornersCopy     the corners of the bounding box to consider (mutable)

src/main/java/net/minestom/server/entity/Entity.java

@@ -16,6 +16,7 @@ import net.minestom.server.event.entity.EntityVelocityEvent;
 import net.minestom.server.event.handler.EventHandler;
 import net.minestom.server.instance.Chunk;
 import net.minestom.server.instance.Instance;
+import net.minestom.server.instance.WorldBorder;
 import net.minestom.server.instance.block.CustomBlock;
 import net.minestom.server.network.packet.PacketWriter;
 import net.minestom.server.network.packet.server.play.*;
@@ -289,8 +290,8 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer {
             this.lastUpdate = time;
 
             // Velocity
-            boolean applyVelocity = (PlayerUtils.isNettyClient(this) && hasVelocity())
-                    || !PlayerUtils.isNettyClient(this);
+            final boolean applyVelocity = !PlayerUtils.isNettyClient(this) ||
+                    (PlayerUtils.isNettyClient(this) && hasVelocity());
             if (applyVelocity) {
                 final float tps = MinecraftServer.TICK_PER_SECOND;
                 float newX = position.getX() + velocity.getX() / tps;
@@ -299,11 +300,9 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer {
 
                 Position newPosition = new Position(newX, newY, newZ);
 
-                //if (!PlayerUtils.isNettyClient(this) && !noGravity) { // players handle gravity by themselves
                 if (!noGravity) {
                     velocity.setY(velocity.getY() - gravityDragPerTick * tps);
                 }
-                // }
 
                 Vector newVelocityOut = new Vector();
                 Vector deltaPos = new Vector(
@@ -313,7 +312,15 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer {
                 );
                 onGround = CollisionUtils.handlePhysics(this, deltaPos, newPosition, newVelocityOut);
 
+                WorldBorder worldBorder = instance.getWorldBorder();
+                if (worldBorder.isInside(newPosition)) {
+                    // Apply velocity + gravity
                     refreshPosition(newPosition);
+                } else {
+                    // Only apply Y velocity/gravity
+                    refreshPosition(position.getX(), newPosition.getY(), position.getZ());
+                }
+
                 velocity.copy(newVelocityOut);
                 velocity.multiply(tps);
 

src/main/java/net/minestom/server/entity/LivingEntity.java

@@ -230,7 +230,7 @@ public abstract class LivingEntity extends Entity implements EquipmentHandler {
             // Additional hearts support
             if (this instanceof Player) {
                 Player player = (Player) this;
-                float additionalHearts = player.getAdditionalHearts();
+                final float additionalHearts = player.getAdditionalHearts();
                 if (additionalHearts > 0) {
                     if (damage > additionalHearts) {
                         damage -= additionalHearts;

src/main/java/net/minestom/server/entity/Player.java

@@ -127,7 +127,7 @@ public class Player extends LivingEntity {
     private PlayerVehicleInformation vehicleInformation = new PlayerVehicleInformation();
 
     // Tick related
-    private final PlayerTickEvent playerTickEvent = new PlayerTickEvent();
+    private final PlayerTickEvent playerTickEvent = new PlayerTickEvent(this);
 
     public Player(UUID uuid, String username, PlayerConnection playerConnection) {
         super(EntityType.PLAYER);

src/main/java/net/minestom/server/event/player/PlayerTickEvent.java

@@ -1,6 +1,17 @@
 package net.minestom.server.event.player;
 
+import net.minestom.server.entity.Player;
 import net.minestom.server.event.Event;
 
 public class PlayerTickEvent extends Event {
+
+    private Player player;
+
+    public PlayerTickEvent(Player player) {
+        this.player = player;
+    }
+
+    public Player getPlayer() {
+        return player;
+    }
 }

src/main/java/net/minestom/server/instance/WorldBorder.java

@@ -1,13 +1,15 @@
 package net.minestom.server.instance;
 
+import net.minestom.server.entity.Entity;
 import net.minestom.server.entity.Player;
 import net.minestom.server.network.packet.server.play.WorldBorderPacket;
+import net.minestom.server.utils.Position;
 
 public class WorldBorder {
 
     private Instance instance;
 
-    private double centerX, centerZ;
+    private float centerX, centerZ;
 
     private volatile double currentDiameter;
 
@@ -33,7 +35,7 @@ public class WorldBorder {
 
     }
 
-    public void setCenter(double centerX, double centerZ) {
+    public void setCenter(float centerX, float centerZ) {
         this.centerX = centerX;
         this.centerZ = centerZ;
         refreshCenter();
@@ -43,7 +45,7 @@ public class WorldBorder {
         return centerX;
     }
 
-    public void setCenterX(double centerX) {
+    public void setCenterX(float centerX) {
         this.centerX = centerX;
         refreshCenter();
     }
@@ -52,7 +54,7 @@ public class WorldBorder {
         return centerZ;
     }
 
-    public void setCenterZ(double centerZ) {
+    public void setCenterZ(float centerZ) {
         this.centerZ = centerZ;
         refreshCenter();
     }
@@ -134,6 +136,31 @@ public class WorldBorder {
         sendPacket(worldBorderPacket);
     }
 
+    /**
+     * Used to know if a position is located inside the world border or not
+     *
+     * @param position the position to check
+     * @return true if {@code position} is inside the world border, false otherwise
+     */
+    public boolean isInside(Position position) {
+        final double radius = getDiameter() / 2d;
+        final boolean checkX = position.getX() < getCenterX() + radius && position.getX() > getCenterX() - radius;
+        if (!checkX)
+            return false;
+        final boolean checkZ = position.getZ() < getCenterZ() + radius && position.getZ() > getCenterZ() - radius;
+        return checkZ;
+    }
+
+    /**
+     * Used to know if an entity is located inside the world border or not
+     *
+     * @param entity the entity to check
+     * @return true if {@code entity} is inside the world border, false otherwise
+     */
+    public boolean isInside(Entity entity) {
+        return isInside(entity.getPosition());
+    }
+
     /**
      * Used to update in real-time the current diameter time
      */