Velocity cleanup

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

@@ -3,11 +3,13 @@ package net.minestom.server.collision;
 import net.minestom.server.entity.Entity;
 import net.minestom.server.instance.Chunk;
 import net.minestom.server.instance.Instance;
+import net.minestom.server.instance.WorldBorder;
 import net.minestom.server.instance.block.Block;
 import net.minestom.server.utils.BlockPosition;
 import net.minestom.server.utils.Position;
 import net.minestom.server.utils.Vector;
 import net.minestom.server.utils.chunk.ChunkUtils;
+import org.jetbrains.annotations.NotNull;
 
 public class CollisionUtils {
 
@@ -172,4 +174,33 @@ public class CollisionUtils {
         return true;
     }
 
+    /**
+     * Applies world border collision.
+     *
+     * @param instance        the instance where the world border is
+     * @param currentPosition the current position
+     * @param newPosition     the future target position
+     * @return the position with the world border collision applied (can be {@code newPosition} if not changed)
+     */
+    public static Position applyWorldBorder(@NotNull Instance instance,
+                                            @NotNull Position currentPosition, @NotNull Position newPosition) {
+        final WorldBorder worldBorder = instance.getWorldBorder();
+        final WorldBorder.CollisionAxis collisionAxis = worldBorder.getCollisionAxis(newPosition);
+        switch (collisionAxis) {
+            case NONE:
+                // Apply velocity + gravity
+                return newPosition;
+            case BOTH:
+                // Apply Y velocity/gravity
+                return new Position(currentPosition.getX(), newPosition.getY(), currentPosition.getZ());
+            case X:
+                // Apply Y/Z velocity/gravity
+                return new Position(currentPosition.getX(), newPosition.getY(), newPosition.getZ());
+            case Z:
+                // Apply X/Y velocity/gravity
+                return new Position(newPosition.getX(), newPosition.getY(), currentPosition.getZ());
+        }
+        throw new IllegalStateException("Something weird happened...");
+    }
+
 }

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

@@ -17,7 +17,6 @@ import net.minestom.server.event.handler.EventHandler;
 import net.minestom.server.instance.Chunk;
 import net.minestom.server.instance.Instance;
 import net.minestom.server.instance.InstanceManager;
-import net.minestom.server.instance.WorldBorder;
 import net.minestom.server.instance.block.CustomBlock;
 import net.minestom.server.network.packet.server.play.*;
 import net.minestom.server.permission.Permission;
@@ -469,10 +468,9 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer, P
 
             if (applyVelocity) {
                 final float tps = MinecraftServer.TICK_PER_SECOND;
-                float newX = position.getX() + velocity.getX() / tps;
+                final float newX = position.getX() + velocity.getX() / tps;
-                float newY = position.getY() + velocity.getY() / tps;
+                final float newY = position.getY() + velocity.getY() / tps;
-                float newZ = position.getZ() + velocity.getZ() / tps;
+                final float newZ = position.getZ() + velocity.getZ() / tps;
-
                 Position newPosition = new Position(newX, newY, newZ);
 
                 if (!noGravity) {
@@ -487,63 +485,52 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer, P
                 );
                 this.onGround = CollisionUtils.handlePhysics(this, deltaPos, newPosition, newVelocityOut);
 
+                // Stop here if the position is the same
+                final boolean updatePosition = !newPosition.isSimilar(position);
+
                 // Check chunk
                 if (!ChunkUtils.isLoaded(instance, newPosition.getX(), newPosition.getZ())) {
                     return;
                 }
 
-                // World border collision
+                // World border and apply the position
+                final Position finalVelocityPosition = CollisionUtils.applyWorldBorder(instance, position, newPosition);
+                if (finalVelocityPosition != null && updatePosition) {
+                    refreshPosition(finalVelocityPosition);
+                }
+
+
+                // Update velocity
                 {
-                    final WorldBorder worldBorder = instance.getWorldBorder();
+                    this.velocity.copy(newVelocityOut);
-                    final WorldBorder.CollisionAxis collisionAxis = worldBorder.getCollisionAxis(newPosition);
+                    this.velocity.multiply(tps);
-                    switch (collisionAxis) {
-                        case NONE:
-                            // Apply velocity + gravity
-                            refreshPosition(newPosition);
-                            break;
-                        case BOTH:
-                            // Apply Y velocity/gravity
-                            refreshPosition(position.getX(), newPosition.getY(), position.getZ());
-                            break;
-                        case X:
-                            // Apply Y/Z velocity/gravity
-                            refreshPosition(position.getX(), newPosition.getY(), newPosition.getZ());
-                            break;
-                        case Z:
-                            // Apply X/Y velocity/gravity
-                            refreshPosition(newPosition.getX(), newPosition.getY(), position.getZ());
-                            break;
-                    }
-                }
 
-                this.velocity.copy(newVelocityOut);
+                    float drag;
-                this.velocity.multiply(tps);
+                    if (onGround) {
+                        final BlockPosition blockPosition = position.toBlockPosition();
+                        final CustomBlock customBlock = instance.getCustomBlock(blockPosition);
+                        if (customBlock != null) {
+                            // Custom drag
+                            drag = customBlock.getDrag(instance, blockPosition);
+                        } else {
+                            // Default ground drag
+                            drag = 0.5f;
+                        }
 
-                float drag;
+                        // Stop player velocity
-                if (onGround) {
+                        if (PlayerUtils.isNettyClient(this)) {
-                    final BlockPosition blockPosition = position.toBlockPosition();
+                            velocity.zero();
-                    final CustomBlock customBlock = instance.getCustomBlock(blockPosition);
+                        }
-                    if (customBlock != null) {
-                        // Custom drag
-                        drag = customBlock.getDrag(instance, blockPosition);
                     } else {
-                        // Default ground drag
+                        drag = 0.98f; // air drag
-                        drag = 0.5f;
                     }
 
-                    // Stop player velocity
+                    this.velocity.setX(velocity.getX() * drag);
-                    if (PlayerUtils.isNettyClient(this)) {
+                    this.velocity.setZ(velocity.getZ() * drag);
-                        velocity.zero();
-                    }
-                } else {
-                    drag = 0.98f; // air drag
                 }
 
-                this.velocity.setX(velocity.getX() * drag);
+                // Synchronization and packets...
-                this.velocity.setZ(velocity.getZ() * drag);
-
                 sendSynchronization();
-
                 if (shouldSendVelocityUpdate(time)) {
                     sendVelocityPacket();
                     lastVelocityUpdateTime = time;