From ffaebece849b6a89bad8051190e2a4dfe4a77239 Mon Sep 17 00:00:00 2001
From: Bixilon <bixilon@bixilon.de>
Date: Sun, 25 Jun 2023 01:40:02 +0200
Subject: [PATCH] falling block entity physics

---
 .../entities/item/FallingBlockEntity.kt       |  6 +++
 .../entities/item/FallingBlockPhysics.kt      | 44 +++++++++++++++++++
 .../physics/entities/item/PrimedTNTPhysics.kt |  1 +
 3 files changed, 51 insertions(+)
 create mode 100644 src/main/java/de/bixilon/minosoft/physics/entities/item/FallingBlockPhysics.kt

diff --git a/src/main/java/de/bixilon/minosoft/data/entities/entities/item/FallingBlockEntity.kt b/src/main/java/de/bixilon/minosoft/data/entities/entities/item/FallingBlockEntity.kt
index b8c6d977a..528b6eb8c 100644
--- a/src/main/java/de/bixilon/minosoft/data/entities/entities/item/FallingBlockEntity.kt
+++ b/src/main/java/de/bixilon/minosoft/data/entities/entities/item/FallingBlockEntity.kt
@@ -24,6 +24,7 @@ import de.bixilon.minosoft.data.registries.entities.EntityFactory
 import de.bixilon.minosoft.data.registries.entities.EntityType
 import de.bixilon.minosoft.data.registries.identified.Namespaces.minecraft
 import de.bixilon.minosoft.data.registries.identified.ResourceLocation
+import de.bixilon.minosoft.physics.entities.item.FallingBlockPhysics
 import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
 
 class FallingBlockEntity(connection: PlayConnection, entityType: EntityType, data: EntityData, position: Vec3d, rotation: EntityRotation) : Entity(connection, entityType, data, position, rotation) {
@@ -38,11 +39,16 @@ class FallingBlockEntity(connection: PlayConnection, entityType: EntityType, dat
 
 
     override fun onAttack(attacker: Entity): Boolean = false
+    override fun createPhysics() = FallingBlockPhysics(this)
 
     override fun setObjectData(data: Int) {
         blockState = connection.registries.blockState.getOrNull(data)
     }
 
+    override fun tick() {
+        if (blockState == null) return // TODO: discard
+    }
+
     companion object : EntityFactory<FallingBlockEntity> {
         override val identifier: ResourceLocation = minecraft("falling_block")
         private val SPAWN_POSITION_DATA = EntityDataField("FALLING_BLOCK_SPAWN_POSITION")
diff --git a/src/main/java/de/bixilon/minosoft/physics/entities/item/FallingBlockPhysics.kt b/src/main/java/de/bixilon/minosoft/physics/entities/item/FallingBlockPhysics.kt
new file mode 100644
index 000000000..cf45c474e
--- /dev/null
+++ b/src/main/java/de/bixilon/minosoft/physics/entities/item/FallingBlockPhysics.kt
@@ -0,0 +1,44 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 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.physics.entities.item
+
+import de.bixilon.kotlinglm.vec3.Vec3d
+import de.bixilon.minosoft.data.entities.entities.item.FallingBlockEntity
+import de.bixilon.minosoft.physics.PhysicsConstants
+import de.bixilon.minosoft.physics.entities.EntityPhysics
+
+class FallingBlockPhysics(entity: FallingBlockEntity) : EntityPhysics<FallingBlockEntity>(entity) {
+    // TODO: test
+
+
+    private fun move() {
+        if (entity.hasGravity) {
+            this.velocity = this.velocity + GRAVITY
+        }
+
+        this.move(this.velocity)
+
+        this.velocity = this.velocity * PhysicsConstants.AIR_RESISTANCE
+    }
+
+    override fun tick() {
+        move()
+
+        super.tick()
+    }
+
+    companion object {
+        val GRAVITY = Vec3d(0.0, -0.04, 0.0)
+    }
+}
diff --git a/src/main/java/de/bixilon/minosoft/physics/entities/item/PrimedTNTPhysics.kt b/src/main/java/de/bixilon/minosoft/physics/entities/item/PrimedTNTPhysics.kt
index b07ddaa36..72b09a28f 100644
--- a/src/main/java/de/bixilon/minosoft/physics/entities/item/PrimedTNTPhysics.kt
+++ b/src/main/java/de/bixilon/minosoft/physics/entities/item/PrimedTNTPhysics.kt
@@ -19,6 +19,7 @@ import de.bixilon.minosoft.physics.PhysicsConstants
 import de.bixilon.minosoft.physics.entities.EntityPhysics
 
 class PrimedTNTPhysics(entity: PrimedTNT) : EntityPhysics<PrimedTNT>(entity) {
+    // TODO: test
 
 
     private fun move() {