animate wall bumps

board.gd

@@ -15,10 +15,16 @@ func top_left_aabb() -> AABB:
 func bottom_right_aabb() -> AABB:
 	return AABB(position + Vector3(dims.x, 0, dims.y) + Vector3(1,0,2), Vector3.ONE*0.1)
 
-# todo: Array[Piece]
-func pieces() -> Array:
-	# todo: sort for consistency
-	return get_children()
+func pieces() -> Array[Piece]:
+	var sorted: Array[Piece] = []
+	for child in get_children():
+		if child is Piece:
+			sorted.push_back(child)
+	# important for consistency.
+	# everything involving pieces is done top to bottom, then left to right
+	# expensive? yes. wasteful? definitely. worth it? i think so.
+	sorted.sort_custom(func(a, b): return a.lpos.y < b.lpos.y or a.lpos.x < b.lpos.x)
+	return sorted
 
 func pieces_at(pos: Vector2i) -> Array[Piece]:
 	var out: Array[Piece] = []

piece.gd

@@ -51,14 +51,13 @@ func do_step(board: Board):
 	# ball being collided *with* gets the remainder of the momentum
 	# EMERGENT COMPLEXITY!??!?
 	if board.solid_at(new_pos):
+		do_bump(move).call()
 		var ball_here := board.type_at(new_pos, Piece.Type.Ball)
 		if ball_here:
-			do_bump(move).call()
 			var rem := lvel % 2
 			ball_here.do_push(lvel/2 + rem).call()
 			lvel = -lvel/2
 		else:
-			lpos = lpos
 			lvel -= move
 		return
 	lpos = new_pos