feat: support input gestures in Trolls

Not too bad! just need to pass the event in a few places. Sometimes 2
moves fire quickly (e.g. down is interpreted as left then down) - i
think this can happen with the joystick as well - maybe a stronger delay
while moving would solve it?

addons/core/Trolls.gd

@@ -20,28 +20,45 @@ static func is_released(event, event_name):
 		return event.is_action_released(event_name)
 	return false
 
+static func is_screen_drag_event(event):
+	if event is InputEventScreenDrag:
+		return (
+			(abs(event.relative.x) > 4 or abs(event.relative.y) > 4)
+			and
+			(abs(event.velocity.x) > 100 or abs(event.velocity.y) > 100))
 
 # returns a normalized Vector2 based checked the controller's movement
-static func move_vector():
+static func move_vector(event=null):
+	if event:
+		if Trolls.is_screen_drag_event(event):
+			var dir = to_cardinal_direction(event.velocity, 100)
+			Log.pr("drag gesture dir", dir)
+			return dir
 	if Dino.focused:
 		return Input.get_vector("ui_left", "ui_right", "ui_up", "ui_down")
 	return Vector2.ZERO
 
-static func grid_move_vector(thresh=0.6):
-	var move = move_vector()
-	if move.x > thresh:
+static func to_cardinal_direction(vec, thresh=0.6):
+	if vec.x > thresh:
 		return Vector2.RIGHT
-	elif move.x < -1*thresh:
+	elif vec.x < -1*thresh:
 		return Vector2.LEFT
-	elif move.y < -1*thresh:
+	elif vec.y < -1*thresh:
 		return Vector2.UP
-	elif move.y > thresh:
+	elif vec.y > thresh:
 		return Vector2.DOWN
 	return Vector2.ZERO
 
+static func grid_move_vector(event=null, thresh=0.6):
+	var move = move_vector(event)
+	return Trolls.to_cardinal_direction(move, thresh)
+
 static func is_move(event):
-	return is_event(event, "ui_left") or is_event(event, "ui_right") or \
-		is_event(event, "ui_up") or is_event(event, "ui_down")
+	return (is_event(event, "ui_left") or
+		is_event(event, "ui_right") or
+		is_event(event, "ui_up") or
+		is_event(event, "ui_down") or
+		is_screen_drag_event(event))
 
 static func is_move_released(event):
 	return is_released(event, "ui_left") or is_released(event, "ui_right") or \

src/puzzle/PuzzleScene.gd

@@ -202,7 +202,7 @@ func _unhandled_input(event):
 		if state == null:
 			Log.warn("No state, ignoring move input")
 			return
-		check_move_input()
+		check_move_input(event)
 	elif Trolls.is_undo(event) and not block_move:
 		if state == null:
 			Log.warn("No state, ignoring undo input")
@@ -236,8 +236,8 @@ func cancel_reset_puzzle():
 var block_move
 var last_move
 
-func check_move_input():
-	var move_vec = Trolls.grid_move_vector()
+func check_move_input(event=null):
+	var move_vec = Trolls.grid_move_vector(event)
 
 	if move_vec != last_move:
 		# allow moving in a new direction