feat: Add option to avoid broadcasting inputs (#230)

Co-authored-by: Tamás Gálffy <[email protected]>

addons/netfox.extras/plugin.cfg

@@ -3,5 +3,5 @@
 name="netfox.extras"
 description="Game-specific utilities for Netfox"
 author="Tamas Galffy"
-version="1.7.0"
+version="1.8.0"
 script="netfox-extras.gd"

addons/netfox.internals/plugin.cfg

@@ -3,5 +3,5 @@
 name="netfox.internals"
 description="Shared internals for netfox addons"
 author="Tamas Galffy"
-version="1.7.0"
+version="1.8.0"
 script="plugin.gd"

addons/netfox.noray/plugin.cfg

@@ -3,5 +3,5 @@
 name="netfox.noray"
 description="Bulletproof your connectivity with noray integration for netfox"
 author="Tamas Galffy"
-version="1.7.0"
+version="1.8.0"
 script="netfox-noray.gd"

addons/netfox/plugin.cfg

@@ -3,5 +3,5 @@
 name="netfox"
 description="Shared internals for netfox addons"
 author="Tamas Galffy"
-version="1.7.0"
+version="1.8.0"
 script="netfox.gd"

addons/netfox/rollback/rollback-synchronizer.gd

@@ -6,8 +6,14 @@ class_name RollbackSynchronizer
 
 @export var root: Node = get_parent()
 @export var state_properties: Array[String]
+
+@export_subgroup("Inputs")
 @export var input_properties: Array[String]
 
+## This will broadcast input to all peers, turning this off will limit to sending it to the server only.
+## Turning this off is recommended to save bandwith and reduce cheating risks.
+@export var enable_input_broadcast: bool = true
+
 var _record_state_props: Array[PropertyEntry] = []
 var _record_input_props: Array[PropertyEntry] = []
 var _auth_state_props: Array[PropertyEntry] = []
@@ -186,7 +192,7 @@ func _after_tick(_delta, _tick):
 					inputs[property] = []
 				inputs[property].push_back(tick_input[property])
 
-		rpc("_submit_input", inputs, NetworkTime.tick)
+		_attempt_submit_input(inputs)
 
 	while _states.size() > NetworkRollback.history_limit:
 		_states.erase(_states.keys().min())
@@ -196,6 +202,13 @@ func _after_tick(_delta, _tick):
 
 	_freshness_store.trim()
 
+func _attempt_submit_input(input: Dictionary):
+	# TODO: Default to input broadcast in mesh network setups
+	if enable_input_broadcast:
+		rpc("_submit_input", input, NetworkTime.tick)
+	elif not multiplayer.is_server():
+		rpc_id(1, "_submit_input", input, NetworkTime.tick)
+
 func _get_history(buffer: Dictionary, tick: int) -> Dictionary:
 	if buffer.has(tick):
 		return buffer[tick]

docs/netfox/nodes/rollback-synchronizer.md

@@ -24,6 +24,11 @@ their respective players.
 
 See [Property paths] on how to specify properties.
 
+*enable_input_broadcast* toggles whether input properties are broadcast to all
+peers, or only to the server. The default is *true* to support legacy
+behaviour. It is recommended to turn this off to lower bandwidth and lessen the
+attack surface for cheating.
+
 > *Note* that it is not recommended to have both state and input properties on
 > the same node. Since nodes with state belong to the server, and nodes with
 > input belong to the player, it is difficult to separate ownership on the same

examples/forest-brawl/scenes/brawler.tscn

@@ -218,6 +218,7 @@ script = ExtResource("7_cmfmx")
 root = NodePath("..")
 state_properties = Array[String]([":transform", ":velocity", ":speed", "Displaceable:mass", "Displaceable:impulse"])
 input_properties = Array[String](["Input:movement", "Input:aim"])
+enable_input_broadcast = false
 
 [node name="MultiplayerSynchronizer" type="MultiplayerSynchronizer" parent="."]
 replication_config = SubResource("SceneReplicationConfig_4cjl8")

examples/forest-brawl/scripts/brawler-controller.gd

@@ -67,7 +67,7 @@ func _ready():
 func _process(delta):
 	# Update animation
 	# Running
-	var movement = Vector3(input.movement.x, 0, input.movement.z) * speed
+	var movement = Vector3(velocity.x, 0, velocity.z) * speed
 	var relative_velocity = quaternion.inverse() * movement
 	relative_velocity.y = 0
 	relative_velocity /= speed