convert units as rigid body

core/tools.gd

@@ -17,3 +17,8 @@ static func get_nearest(from: Node2D, nodes: Array[Node], predicate: Callable) -
 static func jitter(pos: Vector2, min_dist = 0.0, max_dist = 100.0) -> Vector2:
 	# TODO uniform distribution
 	return pos + Vector2.from_angle(randf_range(0.0, PI * 2.0)) * randf_range(min_dist, max_dist)
+
+# Acceleration toward a value
+static func accel(current: Variant, target: Variant, accel: float, delta: float) -> Variant:
+	var diff = target - current
+	return current + min(diff * accel * delta, diff * accel * 0.1)

core/unit.gd

@@ -18,12 +18,13 @@ signal promoted
 		_check_compose()
 			
 @export var hitpoints := 1
-@export var rotation_offset := 0.0
 
 var chief_ref := WeakRef.new()
 
-var target_reached = true
 var target_position := Vector2.ZERO
+var target_linear_velocity := Vector2.ZERO
+var target_angular_velocity := 0.0
+var target_reached := false
 var is_chief := false
 var subordinates := 0
 
@@ -39,16 +40,21 @@ func _compose():
 		if player.code and not Engine.is_editor_hint():
 			add_to_group("player:" + player.code)
 			
-func _physics_process(delta):
-	if not target_reached:
-		# TODO use position instead of global_position, once parented to battlefield
-		var previous = global_position
-		global_position += (target_position - global_position).normalized() * 100.0 * delta
-		var diff = global_position - previous
-		if diff.length() > 0.01:
-			$sprite.rotation = rotation_offset + diff.angle()
-		if global_position.distance_to(target_position) < 5.0:
+func _process(delta):
+	if Engine.is_editor_hint():
+		return
+		
+	if target_reached:
+		target_linear_velocity = Vector2.ZERO
+	else:
+		var current_position = self.global_position
+		var diff = target_position - current_position
+		if diff.length() > 5.0:
+			target_linear_velocity = diff.normalized() * clamp(diff.length() * 0.1, 1.0, 10.0) * 10.0
+		else:
 			target_reached = true
+
+	self.linear_velocity = Tools.accel(self.linear_velocity, target_linear_velocity, 0.4, delta)
 	
 func move_to(pos: Vector2):
 	if pos != target_position:

core/unit.tscn

@@ -1,8 +1,14 @@
-[gd_scene load_steps=2 format=3 uid="uid://bft45rcp7v3a6"]
+[gd_scene load_steps=3 format=3 uid="uid://bft45rcp7v3a6"]
 
 [ext_resource type="Script" path="res://core/unit.gd" id="1_1i367"]
 
-[node name="unit" type="Node2D" groups=["unit"]]
+[sub_resource type="CircleShape2D" id="CircleShape2D_n7nby"]
+
+[node name="unit" type="RigidBody2D" groups=["unit"]]
 script = ExtResource("1_1i367")
 
+[node name="shape" type="CollisionShape2D" parent="."]
+shape = SubResource("CircleShape2D_n7nby")
+disabled = true
+
 [node name="sprite" type="Sprite2D" parent="."]

project.godot

@@ -74,6 +74,11 @@ config/icon="res://tac/assets/icon.png"
 window/size/viewport_width=1280
 window/size/viewport_height=720
 
+[physics]
+
+2d/default_gravity=0.0
+2d/default_gravity_vector=Vector2(0, 0)
+
 [rendering]
 
 renderer/rendering_method="mobile"