Why Board and piece hierarchy in LLD? - Purpose & Use Cases

The Big Idea

Discover how a simple hierarchy can turn chaotic game code into a clean, powerful design!

The Scenario

Imagine trying to build a chess game by writing separate code for each piece and board position without any shared structure or rules.

You would have to manually handle every piece's movement, capture, and interaction individually.

The Problem

This manual approach quickly becomes confusing and full of repeated code.

It's easy to make mistakes, like forgetting a rule or mixing up piece behaviors.

Adding new pieces or changing rules means rewriting lots of code, which is slow and error-prone.

The Solution

Using a board and piece hierarchy organizes the game elements into clear layers.

Pieces inherit common behaviors, and the board manages positions and moves uniformly.

This structure reduces repetition, makes rules easier to enforce, and simplifies adding new pieces or features.

Before vs After

✗ Before

if piece == 'pawn': move_pawn()
if piece == 'rook': move_rook()
if piece == 'bishop': move_bishop()

✓ After

class Piece:
    def move(self): pass

class Pawn(Piece):
    def move(self):
        # pawn move logic
        pass

class Rook(Piece):
    def move(self):
        # rook move logic
        pass

What It Enables

This hierarchy enables building complex board games that are easy to maintain, extend, and understand.

Real Life Example

Chess apps use board and piece hierarchies to handle all pieces with shared rules and unique moves, making the game logic clean and scalable.

Key Takeaways

Manual coding of each piece and move is repetitive and error-prone.

A hierarchy groups shared behaviors and simplifies management.

It makes adding new pieces or rules easier and safer.