snap pieces to grid

game/src/Main.tscn

@@ -122,5 +122,5 @@ __meta__ = {
 
 [node name="GameState" type="Node" parent="."]
 script = ExtResource( 3 )
-[connection signal="state_changed" from="GameState" to="HSplitContainer/Taquin" method="_on_GameState_state_changed"]
 [connection signal="state_changed" from="GameState" to="." method="_on_GameState_state_changed"]
+[connection signal="state_changed" from="GameState" to="HSplitContainer/Taquin" method="_on_GameState_state_changed"]

game/src/Piece.gd

@@ -5,7 +5,8 @@ class_name Piece
 export var size: int = 160
 
 var number: int = 0
-var taquin_position = Vector2(0, 0)
+var taquin_position = Vector2.ZERO
+var taquin_index = Vector2.ZERO
 var piece_scale = Vector2(0.25, 0.25)
 
 func _ready() -> void:

game/src/Taquin.gd

@@ -26,6 +26,7 @@ var swipe = Vector2(0, 0)
 var is_sliding = false
 var current_sliding_piece: Piece = null
 var current_origin = Vector2.ZERO
+var current_goal = Vector2.ZERO
 var current_axis = Vector2.ZERO
 var current_slide = Vector2.ZERO
 var local_min_position = Vector2.ZERO
@@ -40,11 +41,11 @@ func compute_piece_size() -> int:
 	return int(min(w_size, h_size))
 
 func compute_padding(piece_size: int) -> Vector2:
-	var padding = Vector2(0, 0)
-	padding.x = width - columns * piece_size - (columns - 1) * interpiece
-	padding.y = height - rows * piece_size - (rows - 1) * interpiece
-	padding = padding / Vector2(2, 2)
-	return padding
+	var p = Vector2(0, 0)
+	p.x = width - columns * piece_size - (columns - 1) * interpiece
+	p.y = height - rows * piece_size - (rows - 1) * interpiece
+	p = p / Vector2(2, 2)
+	return p
 
 func _ready() -> void:
 	$AnimationPlayer/MockPiece.visible = false
@@ -67,6 +68,7 @@ func _ready() -> void:
 			piece.size = piece_size
 			piece.position = position_for_index(Vector2(c, r), piece.size)
 			piece.number = 1 + c + r * columns
+			piece.taquin_index = Vector2(c, r)
 			piece.piece_scale = Vector2((float(piece_size) / width), (float(piece_size) / height))
 			piece.taquin_position = Vector2(float(piece.position.x) / width, float(piece.position.y) / height)
 
@@ -128,6 +130,7 @@ func _input(event):
 				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_goal = current_sliding_piece.position + local_end_position
 		current_slide += swipe
 		if current_sliding_piece != null:
 			var delta = current_slide.project(current_axis)
@@ -139,26 +142,26 @@ func _input(event):
 #		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)
+			if current_sliding_piece != null:
+				var current_position = current_sliding_piece.position
+				if current_position.distance_to(current_origin) > current_position.distance_to(current_goal):
+					current_sliding_piece.position = current_goal
+					var origin_taquin_position = current_sliding_piece.taquin_index
+					swap(missing_piece, origin_taquin_position)
+					missing_piece = origin_taquin_position
+				else:
+					current_sliding_piece.position = current_origin
 
 func debug_print_direction(direction: int):
 	match direction:
 		Direction.UP:
-			print("Direction UP")
+			print("Direction ⬆️ UP")
 		Direction.DOWN:
-			print("Direction DOWN")
+			print("Direction ⬇️ DOWN")
 		Direction.LEFT:
-			print("Direction LEFT")
+			print("Direction ⬅️ LEFT")
 		Direction.RIGHT:
-			print("Direction RIGHT")
+			print("Direction ➡️ RIGHT")
 		_:
 			assert(false)
 
@@ -202,7 +205,7 @@ func sliding_piece_for_direction(direction) -> Piece:
 	
 	if (destination.x < 0 || destination.x >= columns
 	|| destination.y < 0 || destination.y >= rows):
-		print("impossible move")
+		print("\/!\\ Impossible move")
 		return null
 	return pieces[destination.x][destination.y]
 
@@ -255,7 +258,9 @@ func move_piece(direction) -> bool:
 func swap(src: Vector2, dst: Vector2) -> void:
 	var tmp: Piece = pieces[src.x][src.y]
 	pieces[src.x][src.y] = pieces[dst.x][dst.y]
+	pieces[src.x][src.y].taquin_index = src
 	pieces[dst.x][dst.y] = tmp
+	tmp.taquin_position = dst
 #	pieces[src.x][src.y].position = position_for_index(src, tmp.size)
 #	pieces[dst.x][dst.y].position = position_for_index(dst, tmp.size)