NS-23: Autostep down+forward to walk off bump edges

client/scripts/player.gd

@@ -1,8 +1,8 @@
 extends CharacterBody3D
 
 ## NS-23: Nav agent suggests waypoints; arrival uses stored server goal only (not agent “finished”).
-## NS-19 bumps: thin box colliders need **auto-step** (`test_move` up+forward); Y steering alone
-## is not enough for vertical faces.
+## NS-19 bumps: **autostep** via `test_move` — up+forward to mount, down+forward to leave (pure down
+## hits the bump volume you’re standing on).
 
 const MOVE_SPEED: float = 5.0
 const ARRIVE_EPS: float = 0.35
@@ -10,10 +10,11 @@ const VERT_ARRIVE_EPS: float = 0.16
 const MAX_CLIMB_SPEED: float = 2.6
 const MAX_DESCENT_SPEED: float = 2.2
 const DIRECT_APPROACH_RADIUS: float = 0.85
-## NS-19 bumps ≤ ~0.15 m; probe slightly above for capsule + nav tolerance.
 const STEP_MAX_HEIGHT: float = 0.32
 const STEP_PROBE_FWD: float = 0.38
 const STUCK_HORIZ_SPEED: float = 0.28
+## Drop tries when leaving a bump (combined with forward over the lip).
+const LEDGE_DROP_STEPS: PackedFloat32Array = PackedFloat32Array([0.08, 0.12, 0.18, 0.24, 0.32])
 
 var _has_walk_goal: bool = false
 var _auth_walk_goal: Vector3 = Vector3.ZERO
@@ -55,19 +56,27 @@ func _steer_toward_world_point(point: Vector3) -> void:
 
 
 ## Godot `test_move`: returns **true** if the motion would hit something (blocked).
-func _try_autostep(delta: float) -> bool:
+func _try_autostep(delta: float, full_to_goal: Vector3) -> bool:
 	var to_goal_h: Vector3 = Vector3(
-		_auth_walk_goal.x - global_position.x, 0.0, _auth_walk_goal.z - global_position.z
+		full_to_goal.x, 0.0, full_to_goal.z
 	)
 	if to_goal_h.length_squared() < 0.0225:
 		return false
 	var dir_h: Vector3 = to_goal_h.normalized()
 	var fwd_len: float = maxf(MOVE_SPEED * delta, 0.1)
 	var motion_fwd: Vector3 = dir_h * minf(fwd_len, STEP_PROBE_FWD)
-	var motion_up: Vector3 = Vector3(0.0, STEP_MAX_HEIGHT, 0.0)
 	var xf: Transform3D = global_transform
 	if not test_move(xf, motion_fwd):
 		return false
+	if full_to_goal.y > 0.02:
+		return _autostep_up(xf, motion_fwd, dir_h)
+	if full_to_goal.y < -0.02:
+		return _autostep_down(xf, motion_fwd, dir_h)
+	return false
+
+
+func _autostep_up(xf: Transform3D, motion_fwd: Vector3, dir_h: Vector3) -> bool:
+	var motion_up: Vector3 = Vector3(0.0, STEP_MAX_HEIGHT, 0.0)
 	if test_move(xf, motion_up):
 		return false
 	var xf_up := Transform3D(xf.basis, xf.origin + motion_up)
@@ -80,6 +89,20 @@ func _try_autostep(delta: float) -> bool:
 	return true
 
 
+func _autostep_down(xf: Transform3D, motion_fwd: Vector3, dir_h: Vector3) -> bool:
+	for i: int in range(LEDGE_DROP_STEPS.size()):
+		var drop: float = LEDGE_DROP_STEPS[i]
+		var motion_off: Vector3 = motion_fwd + Vector3(0.0, -drop, 0.0)
+		if test_move(xf, motion_off):
+			continue
+		global_position += motion_off
+		velocity.x = dir_h.x * MOVE_SPEED
+		velocity.z = dir_h.z * MOVE_SPEED
+		velocity.y = -minf(MAX_DESCENT_SPEED, 1.2)
+		return true
+	return false
+
+
 func _physics_process(delta: float) -> void:
 	if not _has_walk_goal:
 		velocity = Vector3.ZERO
@@ -129,6 +152,8 @@ func _maybe_autostep_after_slide(
 	var hspd: float = Vector2(velocity.x, velocity.z).length()
 	var want_step: bool = hspd < STUCK_HORIZ_SPEED
 	if not want_step and is_on_wall():
-		want_step = full_to_goal.y > 0.03 and horiz_dist > 0.12
-	if want_step and _try_autostep(delta):
+		want_step = horiz_dist > 0.12 and (
+			full_to_goal.y > 0.03 or full_to_goal.y < -0.03
+		)
+	if want_step and _try_autostep(delta, full_to_goal):
 		move_and_slide()