[WIP] Add Multiplayer Example

Cargo.toml

@@ -13,7 +13,7 @@ members = [
     "itest/rust",
     "itest/repo-tweak",
     "examples/dodge-the-creeps/rust",
-    "examples/hot-reload/rust",
+    "examples/hot-reload/rust", "examples/multiplayer-lan/rust",
 ]
 
 # Note about Jetbrains IDEs: "IDE Sync" (Refresh Cargo projects) may cause static analysis errors such as

examples/multiplayer-lan/godot/.godot/extension_list.cfg

@@ -0,0 +1 @@
+res://rust.gdextension

examples/multiplayer-lan/godot/README.md

@@ -0,0 +1,15 @@
+# Multiplayer Bomber
+
+A multiplayer implementation of the classic bomberman game.
+One of the players should press **Host**, while other player(s)
+should type in the host's IP address and press **Join**.
+
+Language: GDScript
+
+Renderer: Compatibility
+
+Check out this demo on the asset library: https://godotengine.org/asset-library/asset/139
+
+## Screenshots
+
+![Screenshot](screenshots/bomber.png)

examples/multiplayer-lan/godot/bomb.gd

@@ -0,0 +1,34 @@
+extends Area2D
+
+var in_area: Array = []
+var from_player: int
+
+# Called from the animation.
+func explode():
+	if not is_multiplayer_authority():
+		# Explode only on authority.
+		return
+	for p in in_area:
+		if p.has_method("exploded"):
+			# Checks if there is wall in between bomb and the object
+			var world_state: PhysicsDirectSpaceState2D = get_world_2d().direct_space_state
+			var query := PhysicsRayQueryParameters2D.create(position, p.position)
+			query.hit_from_inside = true
+			var result: Dictionary  = world_state.intersect_ray(query)
+			if not result.collider is TileMap:
+				# Exploded can only be called by the authority, but will also be called locally.
+				p.exploded.rpc(from_player)
+
+
+func done():
+	if is_multiplayer_authority():
+		queue_free()
+
+
+func _on_bomb_body_enter(body):
+	if not body in in_area:
+		in_area.append(body)
+
+
+func _on_bomb_body_exit(body):
+	in_area.erase(body)

examples/multiplayer-lan/godot/bomb.tscn

@@ -0,0 +1,134 @@
+[gd_scene load_steps=9 format=3 uid="uid://enwoaqi0rnei"]
+
+[ext_resource type="Script" path="res://bomb.gd" id="1"]
+[ext_resource type="Texture2D" uid="uid://bdomqql6y50po" path="res://brickfloor.png" id="2"]
+[ext_resource type="Texture2D" uid="uid://drfbkdqmj0gu2" path="res://explosion.png" id="3"]
+
+[sub_resource type="RectangleShape2D" id="RectangleShape2D_1ih13"]
+size = Vector2(16, 192)
+
+[sub_resource type="RectangleShape2D" id="RectangleShape2D_whso6"]
+size = Vector2(192, 16)
+
+[sub_resource type="Curve" id="Curve_4yges"]
+max_value = 2.0
+_data = [Vector2(0.00150494, 0.398437), 0.0, 0.0, 0, 0, Vector2(0.0152287, 1.42969), 0.0, 0.0, 0, 0, Vector2(0.478607, 1.30078), 0.0, 0.0, 0, 0, Vector2(1, 0.291016), 0.0, 0.0, 0, 0]
+point_count = 4
+
+[sub_resource type="Animation" id="Animation_21j5c"]
+length = 4.0
+tracks/0/type = "value"
+tracks/0/imported = false
+tracks/0/enabled = true
+tracks/0/path = NodePath("Sprite:self_modulate")
+tracks/0/interp = 1
+tracks/0/loop_wrap = true
+tracks/0/keys = {
+"times": PackedFloat32Array(0, 0.4, 0.6, 0.8, 1.1, 1.3, 1.5, 1.8, 1.9, 2, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 3),
+"transitions": PackedFloat32Array(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+"update": 0,
+"values": [Color(1, 1, 1, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(8, 8, 8, 1), Color(1, 1, 1, 1), Color(1, 1, 1, 0)]
+}
+tracks/1/type = "method"
+tracks/1/imported = false
+tracks/1/enabled = true
+tracks/1/path = NodePath(".")
+tracks/1/interp = 1
+tracks/1/loop_wrap = true
+tracks/1/keys = {
+"times": PackedFloat32Array(2.8, 3.4),
+"transitions": PackedFloat32Array(1, 1),
+"values": [{
+"args": [],
+"method": &"explode"
+}, {
+"args": [],
+"method": &"done"
+}]
+}
+tracks/2/type = "value"
+tracks/2/imported = false
+tracks/2/enabled = true
+tracks/2/path = NodePath("Explosion1:emitting")
+tracks/2/interp = 1
+tracks/2/loop_wrap = true
+tracks/2/keys = {
+"times": PackedFloat32Array(0, 2.8),
+"transitions": PackedFloat32Array(1, 1),
+"update": 1,
+"values": [false, true]
+}
+tracks/3/type = "value"
+tracks/3/imported = false
+tracks/3/enabled = true
+tracks/3/path = NodePath("Explosion2:emitting")
+tracks/3/interp = 1
+tracks/3/loop_wrap = true
+tracks/3/keys = {
+"times": PackedFloat32Array(0, 2.8),
+"transitions": PackedFloat32Array(1, 1),
+"update": 1,
+"values": [false, true]
+}
+
+[sub_resource type="AnimationLibrary" id="AnimationLibrary_h2w7m"]
+_data = {
+"anim": SubResource("Animation_21j5c")
+}
+
+[node name="Bomb" type="Area2D"]
+monitorable = false
+script = ExtResource("1")
+
+[node name="Sprite" type="Sprite2D" parent="."]
+self_modulate = Color(1, 1, 1, 0)
+position = Vector2(-2.92606, -2.92606)
+texture = ExtResource("2")
+region_enabled = true
+region_rect = Rect2(144, 0, 48, 48)
+
+[node name="Shape1" type="CollisionShape2D" parent="."]
+shape = SubResource("RectangleShape2D_1ih13")
+
+[node name="Shape2" type="CollisionShape2D" parent="."]
+shape = SubResource("RectangleShape2D_whso6")
+
+[node name="Explosion1" type="CPUParticles2D" parent="."]
+emitting = false
+lifetime = 0.5
+one_shot = true
+explosiveness = 0.95
+texture = ExtResource("3")
+emission_shape = 3
+emission_rect_extents = Vector2(80, 1)
+gravity = Vector2(0, 0)
+initial_velocity_min = 1.0
+initial_velocity_max = 1.0
+angular_velocity_min = 187.35
+angular_velocity_max = 188.35
+scale_amount_curve = SubResource("Curve_4yges")
+
+[node name="Explosion2" type="CPUParticles2D" parent="."]
+rotation = 1.57162
+emitting = false
+lifetime = 0.5
+one_shot = true
+explosiveness = 0.95
+texture = ExtResource("3")
+emission_shape = 3
+emission_rect_extents = Vector2(80, 1)
+gravity = Vector2(0, 0)
+initial_velocity_min = 1.0
+initial_velocity_max = 1.0
+angular_velocity_min = 187.35
+angular_velocity_max = 188.35
+scale_amount_curve = SubResource("Curve_4yges")
+
+[node name="AnimationPlayer" type="AnimationPlayer" parent="."]
+autoplay = "anim"
+libraries = {
+"": SubResource("AnimationLibrary_h2w7m")
+}
+
+[connection signal="body_entered" from="." to="." method="_on_bomb_body_enter"]
+[connection signal="body_exited" from="." to="." method="_on_bomb_body_exit"]

examples/multiplayer-lan/godot/bomb_spawner.gd

@@ -0,0 +1,14 @@
+extends MultiplayerSpawner
+
+func _init():
+	spawn_function = _spawn_bomb
+
+
+func _spawn_bomb(data):
+	print(data)
+	if data.size() != 2 or typeof(data[0]) != TYPE_VECTOR2 or typeof(data[1]) != TYPE_INT:
+		return null
+	var bomb = preload("res://bomb.tscn").instantiate()
+	bomb.position = data[0]
+	bomb.from_player = data[1]
+	return bomb

examples/multiplayer-lan/godot/gamestate.gd

@@ -0,0 +1,149 @@
+extends Node
+
+# Default game server port. Can be any number between 1024 and 49151.
+# Not on the list of registered or common ports as of November 2020:
+# https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
+const DEFAULT_PORT = 10567
+
+# Max number of players.
+const MAX_PEERS = 12
+
+var peer = null
+
+# Name for my player.
+var player_name = "The Warrior"
+
+# Names for remote players in id:name format.
+var players = {}
+var players_ready = []
+
+# Signals to let lobby GUI know what's going on.
+signal player_list_changed()
+signal connection_failed()
+signal connection_succeeded()
+signal game_ended()
+signal game_error(what)
+
+# Callback from SceneTree.
+func _player_connected(id):
+	# Registration of a client beings here, tell the connected player that we are here.
+	register_player.rpc_id(id, player_name)
+
+
+# Callback from SceneTree.
+func _player_disconnected(id):
+	if has_node("/root/World"): # Game is in progress.
+		if multiplayer.is_server():
+			game_error.emit("Player " + players[id] + " disconnected")
+			end_game()
+	else: # Game is not in progress.
+		# Unregister this player.
+		unregister_player(id)
+
+
+# Callback from SceneTree, only for clients (not server).
+func _connected_ok():
+	# We just connected to a server
+	connection_succeeded.emit()
+
+
+# Callback from SceneTree, only for clients (not server).
+func _server_disconnected():
+	game_error.emit("Server disconnected")
+	end_game()
+
+
+# Callback from SceneTree, only for clients (not server).
+func _connected_fail():
+	multiplayer.set_network_peer(null) # Remove peer
+	connection_failed.emit()
+
+
+# Lobby management functions.
+@rpc("any_peer")
+func register_player(new_player_name):
+	var id = multiplayer.get_remote_sender_id()
+	players[id] = new_player_name
+	player_list_changed.emit()
+
+
+func unregister_player(id):
+	players.erase(id)
+	player_list_changed.emit()
+
+
+@rpc("call_local")
+func load_world():
+	# Change scene.
+	var world = load("res://world.tscn").instantiate()
+	get_tree().get_root().add_child(world)
+	get_tree().get_root().get_node("Lobby").hide()
+
+	# Set up score.
+	world.get_node("Score").add_player(multiplayer.get_unique_id(), player_name)
+	for pn in players:
+		world.get_node("Score").add_player(pn, players[pn])
+	get_tree().set_pause(false) # Unpause and unleash the game!
+
+
+func host_game(new_player_name):
+	player_name = new_player_name
+	peer = ENetMultiplayerPeer.new()
+	peer.create_server(DEFAULT_PORT, MAX_PEERS)
+	multiplayer.set_multiplayer_peer(peer)
+
+
+func join_game(ip, new_player_name):
+	player_name = new_player_name
+	peer = ENetMultiplayerPeer.new()
+	peer.create_client(ip, DEFAULT_PORT)
+	multiplayer.set_multiplayer_peer(peer)
+
+
+func get_player_list():
+	return players.values()
+
+
+func get_player_name():
+	return player_name
+
+
+func begin_game():
+	assert(multiplayer.is_server())
+	load_world.rpc()
+
+	var world = get_tree().get_root().get_node("World")
+	var player_scene = load("res://player.tscn")
+
+	# Create a dictionary with peer id and respective spawn points, could be improved by randomizing.
+	var spawn_points = {}
+	spawn_points[1] = 0 # Server in spawn point 0.
+	var spawn_point_idx = 1
+	for p in players:
+		spawn_points[p] = spawn_point_idx
+		spawn_point_idx += 1
+
+	for p_id in spawn_points:
+		var spawn_pos = world.get_node("SpawnPoints/" + str(spawn_points[p_id])).position
+		var player = player_scene.instantiate()
+		player.synced_position = spawn_pos
+		player.name = str(p_id)
+		player.set_player_name(player_name if p_id == multiplayer.get_unique_id() else players[p_id])
+		world.get_node("Players").add_child(player)
+
+
+func end_game():
+	if has_node("/root/World"): # Game is in progress.
+		# End it
+		get_node("/root/World").queue_free()
+
+	game_ended.emit()
+	players.clear()
+
+
+func _ready():
+	multiplayer.peer_connected.connect(_player_connected)
+	multiplayer.peer_disconnected.connect(_player_disconnected)
+	multiplayer.connected_to_server.connect(_connected_ok)
+	multiplayer.connection_failed.connect(_connected_fail)
+	multiplayer.server_disconnected.connect(_server_disconnected)