entities: rework velocity

src/main/java/de/bixilon/minosoft/data/VelocityHandler.java

@@ -1,33 +0,0 @@
-/*
- * Minosoft
- * Copyright (C) 2020 Moritz Zwerger
- *
- * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
- *
- * This software is not affiliated with Mojang AB, the original developer of Minecraft.
- */
-
-package de.bixilon.minosoft.data;
-
-import de.bixilon.minosoft.data.entities.Velocity;
-import de.bixilon.minosoft.data.entities.entities.Entity;
-import de.bixilon.minosoft.protocol.network.connection.PlayConnection;
-
-import java.util.HashMap;
-
-public class VelocityHandler {
-    private final PlayConnection connection;
-    private final HashMap<Entity, Velocity> entities = new HashMap<>();
-
-    public VelocityHandler(PlayConnection connection) {
-        this.connection = connection;
-    }
-
-    public void handleVelocity(Entity entity, Velocity velocity) {
-        // ToDo
-    }
-}

src/main/java/de/bixilon/minosoft/data/entities/Velocity.kt

@@ -1,20 +0,0 @@
-/*
- * Minosoft
- * Copyright (C) 2020 Moritz Zwerger
- *
- * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
- *
- * This software is not affiliated with Mojang AB, the original developer of Minecraft.
- */
-package de.bixilon.minosoft.data.entities
-
-data class Velocity(val x: Short, val y: Short, val z: Short) {
-
-    override fun toString(): String {
-        return "($x $y $z)"
-    }
-}

src/main/java/de/bixilon/minosoft/data/entities/entities/Entity.kt

@@ -26,7 +26,9 @@ import de.bixilon.minosoft.data.mappings.entities.EntityType
 import de.bixilon.minosoft.data.text.ChatComponent
 import de.bixilon.minosoft.gui.rendering.chunk.VoxelShape
 import de.bixilon.minosoft.gui.rendering.chunk.models.AABB
+import de.bixilon.minosoft.gui.rendering.util.VecUtil
 import de.bixilon.minosoft.protocol.network.connection.PlayConnection
+import de.bixilon.minosoft.protocol.protocol.ProtocolDefinition
 import glm_.vec3.Vec3
 import java.lang.reflect.InvocationTargetException
 import java.util.*
@@ -46,6 +48,8 @@ abstract class Entity(
 
     var entityMetaData: EntityMetaData = EntityMetaData(connection)
 
+    var velocity: Vec3? = null
+
     protected open val hasCollisions = true
 
     private val defaultAABB = AABB(
@@ -230,6 +234,22 @@ abstract class Entity(
         return delta
     }
 
+    fun computeTimeStep(deltaTime: Float) {
+        if (! hasNoGravity) {
+            if (velocity == null) {
+                velocity = Vec3(0, deltaTime * ProtocolDefinition.GRAVITY)
+            } else {
+                velocity!!.y += deltaTime * ProtocolDefinition.GRAVITY;
+            }
+        }
+        if (velocity == VecUtil.EMPTY_VEC3) {
+            velocity = null
+        }
+        velocity?.let {
+            move(velocity!! * deltaTime)
+        }
+    }
+
     private val aabb: AABB
         get() = defaultAABB + position
 

src/main/java/de/bixilon/minosoft/protocol/network/connection/PlayConnection.kt

@@ -15,7 +15,6 @@ package de.bixilon.minosoft.protocol.network.connection
 
 import de.bixilon.minosoft.Minosoft
 import de.bixilon.minosoft.config.StaticConfiguration
-import de.bixilon.minosoft.data.VelocityHandler
 import de.bixilon.minosoft.data.accounts.Account
 import de.bixilon.minosoft.data.assets.MultiAssetsManager
 import de.bixilon.minosoft.data.commands.CommandRootNode
@@ -59,7 +58,6 @@ class PlayConnection(
     val scoreboardManager = ScoreboardManager()
     val mapping = VersionMapping()
     val sender = PacketSender(this)
-    val velocityHandler = VelocityHandler(this)
     lateinit var assetsManager: MultiAssetsManager
         private set
 

src/main/java/de/bixilon/minosoft/protocol/packets/s2c/play/EntityVelocityS2CP.kt

@@ -12,20 +12,20 @@
  */
 package de.bixilon.minosoft.protocol.packets.s2c.play
 
-import de.bixilon.minosoft.data.entities.Velocity
 import de.bixilon.minosoft.protocol.network.connection.PlayConnection
 import de.bixilon.minosoft.protocol.packets.s2c.PlayS2CPacket
 import de.bixilon.minosoft.protocol.protocol.PlayInByteBuffer
+import de.bixilon.minosoft.protocol.protocol.ProtocolDefinition
 import de.bixilon.minosoft.util.logging.Log
+import glm_.vec3.Vec3
 
 class EntityVelocityS2CP(buffer: PlayInByteBuffer) : PlayS2CPacket() {
     val entityId: Int = buffer.readEntityId()
-    val velocity: Velocity = Velocity(buffer.readShort(), buffer.readShort(), buffer.readShort())
+    val velocity: Vec3 = Vec3(buffer.readShort(), buffer.readShort(), buffer.readShort()) * ProtocolDefinition.VELOCITY_CONSTANT
 
     override fun handle(connection: PlayConnection) {
         val entity = connection.world.getEntity(entityId) ?: return
-
+        entity.velocity = velocity
-        connection.velocityHandler.handleVelocity(entity, velocity)
     }
 
     override fun log() {

src/main/java/de/bixilon/minosoft/protocol/packets/s2c/play/PacketSpawnMob.java

@@ -15,7 +15,6 @@ package de.bixilon.minosoft.protocol.packets.s2c.play;
 
 import de.bixilon.minosoft.config.StaticConfiguration;
 import de.bixilon.minosoft.data.entities.EntityRotation;
-import de.bixilon.minosoft.data.entities.Velocity;
 import de.bixilon.minosoft.data.entities.entities.Entity;
 import de.bixilon.minosoft.data.entities.entities.UnknownEntityException;
 import de.bixilon.minosoft.data.entities.meta.EntityMetaData;
@@ -23,6 +22,7 @@ import de.bixilon.minosoft.modding.event.events.EntitySpawnEvent;
 import de.bixilon.minosoft.protocol.network.connection.PlayConnection;
 import de.bixilon.minosoft.protocol.packets.s2c.PlayS2CPacket;
 import de.bixilon.minosoft.protocol.protocol.PlayInByteBuffer;
+import de.bixilon.minosoft.protocol.protocol.ProtocolDefinition;
 import de.bixilon.minosoft.util.logging.Log;
 import glm_.vec3.Vec3;
 
@@ -32,7 +32,7 @@ import static de.bixilon.minosoft.protocol.protocol.ProtocolVersions.*;
 
 public class PacketSpawnMob extends PlayS2CPacket {
     private final int entityId;
-    private final Velocity velocity;
+    private final Vec3 velocity;
     private final Entity entity;
     private UUID entityUUID;
 
@@ -55,7 +55,7 @@ public class PacketSpawnMob extends PlayS2CPacket {
             position = buffer.readEntityPosition();
         }
         EntityRotation rotation = new EntityRotation(buffer.readAngle(), buffer.readAngle(), buffer.readAngle());
-        this.velocity = new Velocity(buffer.readShort(), buffer.readShort(), buffer.readShort());
+        this.velocity = new Vec3(buffer.readShort(), buffer.readShort(), buffer.readShort()).times(ProtocolDefinition.VELOCITY_CONSTANT);
 
         EntityMetaData metaData = null;
         if (buffer.getVersionId() < V_19W34A) {
@@ -82,9 +82,8 @@ public class PacketSpawnMob extends PlayS2CPacket {
     @Override
     public void handle(PlayConnection connection) {
         connection.fireEvent(new EntitySpawnEvent(connection, this));
-
         connection.getWorld().addEntity(this.entityId, this.entityUUID, getEntity());
-        connection.getVelocityHandler().handleVelocity(getEntity(), getVelocity());
+        entity.setVelocity(velocity);
     }
 
     @Override
@@ -95,9 +94,4 @@ public class PacketSpawnMob extends PlayS2CPacket {
     public Entity getEntity() {
         return this.entity;
     }
-
-    public Velocity getVelocity() {
-        return this.velocity;
-    }
-
 }

src/main/java/de/bixilon/minosoft/protocol/packets/s2c/play/PacketSpawnObject.java

@@ -14,13 +14,13 @@
 package de.bixilon.minosoft.protocol.packets.s2c.play;
 
 import de.bixilon.minosoft.data.entities.EntityRotation;
-import de.bixilon.minosoft.data.entities.Velocity;
 import de.bixilon.minosoft.data.entities.entities.Entity;
 import de.bixilon.minosoft.data.mappings.DefaultRegistries;
 import de.bixilon.minosoft.modding.event.events.EntitySpawnEvent;
 import de.bixilon.minosoft.protocol.network.connection.PlayConnection;
 import de.bixilon.minosoft.protocol.packets.s2c.PlayS2CPacket;
 import de.bixilon.minosoft.protocol.protocol.PlayInByteBuffer;
+import de.bixilon.minosoft.protocol.protocol.ProtocolDefinition;
 import de.bixilon.minosoft.util.logging.Log;
 import glm_.vec3.Vec3;
 
@@ -32,7 +32,7 @@ public class PacketSpawnObject extends PlayS2CPacket {
     private final int entityId;
     private UUID entityUUID;
     private final Entity entity;
-    private Velocity velocity;
+    private Vec3 velocity;
 
     public PacketSpawnObject(PlayInByteBuffer buffer) throws Exception {
         this.entityId = buffer.readEntityId();
@@ -58,10 +58,10 @@ public class PacketSpawnObject extends PlayS2CPacket {
 
         if (buffer.getVersionId() < V_15W31A) {
             if (data != 0) {
-                this.velocity = new Velocity(buffer.readShort(), buffer.readShort(), buffer.readShort());
+                this.velocity = new Vec3(buffer.readShort(), buffer.readShort(), buffer.readShort()).times(ProtocolDefinition.VELOCITY_CONSTANT);
             }
         } else {
-            this.velocity = new Velocity(buffer.readShort(), buffer.readShort(), buffer.readShort());
+            this.velocity = new Vec3(buffer.readShort(), buffer.readShort(), buffer.readShort()).times(ProtocolDefinition.VELOCITY_CONSTANT);
         }
 
         if (buffer.getVersionId() < V_19W05A) {
@@ -77,7 +77,7 @@ public class PacketSpawnObject extends PlayS2CPacket {
         connection.fireEvent(new EntitySpawnEvent(connection, this));
 
         connection.getWorld().addEntity(this.entityId, this.entityUUID, getEntity());
-        connection.getVelocityHandler().handleVelocity(getEntity(), getVelocity());
+        entity.setVelocity(velocity);
     }
 
     @Override
@@ -88,9 +88,4 @@ public class PacketSpawnObject extends PlayS2CPacket {
     public Entity getEntity() {
         return this.entity;
     }
-
-    public Velocity getVelocity() {
-        return this.velocity;
-    }
-
 }

src/main/java/de/bixilon/minosoft/protocol/protocol/ProtocolDefinition.java

@@ -93,6 +93,10 @@ public final class ProtocolDefinition {
     public static final int TICKS_PER_SECOND = 20;
     public static final int TICK_TIME = 1000 / TICKS_PER_SECOND;
 
+    public static final float VELOCITY_CONSTANT = 1 / 8000f * TICKS_PER_SECOND;
+
+    public static final float GRAVITY = -10; //  TODO: find the correct value
+
     public static final int SEA_LEVEL_HEIGHT = 62;
 
     public static final float HEIGHT_SEA_LEVEL_MODIFIER = 0.00166667f;