Step 5 - Solution

← Step 5 · Tutorial 1.1 · Step 6 →

---

Here is one way to make rotation use try → check → rollback so we don’t rotate into walls or other pieces.

Updated rotate() on Piece (use import copy at top if you use copy.copy):

def rotate(self, n=1):
    old_offset = self.offset_num
    self.offset_num = (self.offset_num + n) % len(self.offsets)
    if self.check_collision():
        self.offset_num = old_offset

Or without importing copy (since it’s an int):

def rotate(self, n=1):
    old_offset = self.offset_num
    self.offset_num = (self.offset_num + n) % len(self.offsets)
    if self.check_collision():
        self.offset_num = old_offset

What’s going on:

• We save the current rotation index, then apply the new rotation. check_collision() uses the new offsets[self.offset_num], so it detects if the rotated shape is out of bounds or overlapping the board. If so, we restore offset_num so the piece stays in the previous rotation.

Next: clear full rows and add scoring (Step 6).

← Back to Step 5 · Step 6 →