Audio: mood music, ambience, sound effects and creature voices (Kenney CC0 + synthesised); protocol 13

scripts/player/player.gd

@@ -103,3 +103,42 @@ func _physics_process(delta: float) -> void:
 		velocity.z = move_toward(velocity.z, 0, current_speed)
 
 	move_and_slide()
+	_footsteps(delta, swimming)
+
+# --- footsteps (sfx.gd) ------------------------------------------------------------
+
+const STRIDE := 1.9              ## metres between footsteps (walking; a little longer sprinting)
+var _stride := 0.0
+
+## A footstep every stride on the ground, by what's underfoot (a floor
+## piece's wood or stone, snow up high or while it's snowing, else grass);
+## a stroke now and then while swimming. Only you hear your own.
+func _footsteps(dt: float, swimming: bool) -> void:
+	var v := Vector2(velocity.x, velocity.z).length()
+	if v < 1.0 or not (is_on_floor() or swimming):
+		_stride = minf(_stride, STRIDE * 0.6)   # (the first step after stopping comes soon)
+		return
+	_stride += v * dt
+	var gap := STRIDE * (1.2 if v > speed + 0.5 else 1.0) * (1.6 if swimming else 1.0)
+	if _stride < gap:
+		return
+	_stride = 0.0
+	Sfx.me("swim" if swimming else step_sound())
+
+func step_sound() -> String:
+	var q := PhysicsRayQueryParameters3D.create(global_position + Vector3(0, 0.3, 0), global_position - Vector3(0, 0.5, 0))
+	q.exclude = [get_rid()]
+	var hit := get_world_3d().direct_space_state.intersect_ray(q)
+	var c: Object = hit.get("collider")
+	# (a piece's collider is its body or one of its children)
+	for _i in range(3):
+		if not (c is Node):
+			break
+		if (c as Node).is_in_group("piece"):
+			return "step_stone" if String((c as Node).get("item_id")).contains("stone") else "step_wood"
+		c = (c as Node).get_parent()
+	var w: Node = get_parent()
+	var wx: Node = w.get("weather") if w != null else null
+	if wx != null and (String(wx.get("state")) in ["snow", "blizzard"] or global_position.y > float(wx.get("snowline")) - 1.0):
+		return "step_snow"
+	return "step_grass"