Step 4 - Solution

← Step 4 · Tutorial 1.1 · Step 5 →

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Here is one way to add rotation by giving each piece multiple offset lists and a rotate() method. The L piece gets four rotations; O stays one; Z gets two.

# Inside Piece.__init__, example for L with 4 rotations:
if self.type == "L":
    self.offsets = [
        [(0, 0), (0, 1), (0, 2), (1, 2)],   # default
        [(0, 1), (1, 1), (2, 1), (0, 0)],   # 90° CW
        [(1, 0), (1, 1), (1, 2), (0, 0)],   # 180°
        [(0, 1), (1, 1), (2, 1), (2, 2)],   # 270° CW
    ]
elif self.type == "O":
    self.offsets = [[(0, 0), (1, 0), (0, 1), (1, 1)]]
else:  # Z
    self.offsets = [
        [(0, 0), (1, 0), (1, 1), (2, 1)],
        [(1, 0), (1, 1), (0, 1), (0, 2)],
    ]

rotate() method on Piece:

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

In the game loop, key handling (e.g. in run() or your event handler):

if event.key == pygame.K_w:
    self.pieces[0].rotate(1)

What’s going on:

• Each piece type has a list of offset lists. offset_num is the index of the current rotation. render() and check_collision() already use self.offsets[self.offset_num], so they automatically use the new shape after rotation.
• rotate(1) advances the index and wraps with modulo. No collision check yet - that’s Step 5.

Next: only allow rotation if it doesn’t overlap the wall or the board (try → check → rollback).

← Back to Step 4 · Step 5 →