diff --git a/game/src/Taquin.gd b/game/src/Taquin.gd
index f11843d..0cb7f7d 100644
--- a/game/src/Taquin.gd
+++ b/game/src/Taquin.gd
@@ -10,6 +10,8 @@ export var width: int = 512
 export var height: int = 512
 export var difficulty: int = 10
 
+enum Direction { UP, DOWN, LEFT, RIGHT }
+
 var interpiece: int = 4
 var min_padding = 15
 var padding = Vector2(min_padding, min_padding)
@@ -21,6 +23,13 @@ var rng = RandomNumberGenerator.new()
 var current_animation_path: String = "AnimationPlayer/MockPiece:position"
 
 var swipe = Vector2(0, 0)
+var is_sliding = false
+var current_sliding_piece: Piece = null
+var current_origin = Vector2.ZERO
+var current_axis = Vector2.ZERO
+var current_slide = Vector2.ZERO
+var local_min_position = Vector2.ZERO
+var local_max_position = Vector2.ZERO
 
 func position_for_index(index: Vector2, size: int) -> Vector2:
 	return padding + Vector2(index.x * (size + interpiece), index.y * (size + interpiece))
@@ -88,6 +97,9 @@ func _input(event):
 			GameState.State.GAME_OVER:
 				return
 
+	#
+	# Handle keyboard input
+	#
 	if event.is_action_pressed("ui_up"):
 		move_piece(Direction.DOWN)
 	if event.is_action_pressed("ui_down"):
@@ -97,21 +109,102 @@ func _input(event):
 	if event.is_action_pressed("ui_right"):
 		move_piece(Direction.LEFT)
 
+	#
+	# Handle touch input
+	#
 	if event is InputEventScreenDrag:
+#		print("screen drag")
 		swipe = event.relative
-	if event is InputEventScreenTouch:
-		if not event.pressed: # Touch released
+		if not is_sliding:
+			is_sliding = true
+			current_slide = Vector2(0, 0)
 			var angle = swipe.angle()
-			if angle < PI / 4 and angle >= - PI / 4:
-				move_piece(Direction.LEFT)
-			if angle >= PI / 4 and angle < PI - PI / 4:
-				move_piece(Direction.UP)
-			if angle >= - PI + PI / 4 and angle < - PI / 4:
-				move_piece(Direction.DOWN)
-			if angle >= PI - PI / 4 or angle < -PI + PI / 4:
-				move_piece(Direction.RIGHT)
+			var direction = direction_for_angle(angle)
+			debug_print_direction(direction)
+			current_sliding_piece = sliding_piece_for_direction(direction)
+			if current_sliding_piece != null:
+				current_origin = current_sliding_piece.position
+				current_axis = axis_for_direction(direction)
+				var local_end_position = current_axis * (current_sliding_piece.size + interpiece)
+				local_min_position = Vector2(min(0, local_end_position.x), min(0, local_end_position.y))
+				local_max_position = Vector2(max(0, local_end_position.x), max(0, local_end_position.y))
+		current_slide += swipe
+		if current_sliding_piece != null:
+			var delta = current_slide.project(current_axis)
+			delta.x = clamp(delta.x, local_min_position.x, local_max_position.x)
+			delta.y = clamp(delta.y, local_min_position.y, local_max_position.y)
+			current_sliding_piece.position = current_origin + delta
 
-enum Direction { UP, DOWN, LEFT, RIGHT }
+	if event is InputEventScreenTouch:
+#		print("screen touch")
+		if not event.pressed: # Touch released
+			is_sliding = false
+#			var angle = swipe.angle()
+#			if angle < PI / 4 and angle >= - PI / 4:
+#				move_piece(Direction.LEFT)
+#			if angle >= PI / 4 and angle < PI - PI / 4:
+#				move_piece(Direction.UP)
+#			if angle >= - PI + PI / 4 and angle < - PI / 4:
+#				move_piece(Direction.DOWN)
+#			if angle >= PI - PI / 4 or angle < -PI + PI / 4:
+#				move_piece(Direction.RIGHT)
+
+func debug_print_direction(direction: int):
+	match direction:
+		Direction.UP:
+			print("Direction UP")
+		Direction.DOWN:
+			print("Direction DOWN")
+		Direction.LEFT:
+			print("Direction LEFT")
+		Direction.RIGHT:
+			print("Direction RIGHT")
+		_:
+			assert(false)
+
+func axis_for_direction(direction: int) -> Vector2:
+	match direction:
+		Direction.UP:
+			return Vector2.UP
+		Direction.DOWN:
+			return Vector2.DOWN
+		Direction.LEFT:
+			return Vector2.LEFT
+		Direction.RIGHT:
+			return Vector2.RIGHT
+		_:
+			assert(false)
+			return Vector2.ZERO
+
+func direction_for_angle(angle: float) -> int:
+	if angle < PI / 4 and angle >= - PI / 4:
+		return Direction.RIGHT
+	if angle >= PI / 4 and angle < PI - PI / 4:
+		return Direction.DOWN
+	if angle >= - PI + PI / 4 and angle < - PI / 4:
+		return Direction.UP
+	if angle >= PI - PI / 4 or angle < -PI + PI / 4:
+		return Direction.LEFT
+	assert(false)
+	return Direction.DOWN
+	
+func sliding_piece_for_direction(direction) -> Piece:
+	var destination: Vector2 = missing_piece
+	match direction:
+		Direction.UP:
+			destination.y += 1
+		Direction.DOWN:
+			destination.y -= 1
+		Direction.LEFT:
+			destination.x += 1
+		Direction.RIGHT:
+			destination.x -= 1
+	
+	if (destination.x < 0 || destination.x >= columns
+	|| destination.y < 0 || destination.y >= rows):
+		print("impossible move")
+		return null
+	return pieces[destination.x][destination.y]
 
 func move_piece(direction) -> bool:
 	var destination: Vector2 = missing_piece