Prototype Pattern

Intent:
Create new objects by copying (cloning) an existing object, rather than creating from scratch.

When to Use:
When object creation is costly or complex, and you want to avoid creating new instances from scratch.

Key Characteristics:

• Cloning instead of instantiation
• Supports deep or shallow copy
• Useful for performance optimization

Example (PUBG Game: Bullets):

Copy
# bullet.py
import copy

class Bullet:
    def __init__(self, weapon_type, damage, speed, coordinates):
        self.weapon_type = weapon_type
        self.damage = damage
        self.speed = speed
        self.coordinates = coordinates  # (x, y, z)

    def clone(self):
        return copy.deepcopy(self)

    def set_coordinates(self, coordinates):
        self.coordinates = coordinates

    def __str__(self):
        return f"Bullet({self.weapon_type}, Damage: {self.damage}, Speed: {self.speed}, Coordinates: {self.coordinates})"
# bullet.py
import copy

class Bullet:
    def __init__(self, weapon_type, damage, speed, coordinates):
        self.weapon_type = weapon_type
        self.damage = damage
        self.speed = speed
        self.coordinates = coordinates  # (x, y, z)

    def clone(self):
        return copy.deepcopy(self)

    def set_coordinates(self, coordinates):
        self.coordinates = coordinates

    def __str__(self):
        return f"Bullet({self.weapon_type}, Damage: {self.damage}, Speed: {self.speed}, Coordinates: {self.coordinates})"

Copy
# bullet_prototype_manager.py
class BulletPrototypeManager:
    def __init__(self):
        self._prototypes = {}

    def register_prototype(self, name, bullet_prototype):
        self._prototypes[name] = bullet_prototype

    def unregister_prototype(self, name):
        if name in self._prototypes:
            del self._prototypes[name]

    def clone(self, name, new_coordinates):
        bullet = self._prototypes.get(name)
        if not bullet:
            raise ValueError(f"No prototype registered under name '{name}'")
        cloned = bullet.clone()
        cloned.set_coordinates(new_coordinates)
        return cloned
# bullet_prototype_manager.py
class BulletPrototypeManager:
    def __init__(self):
        self._prototypes = {}

    def register_prototype(self, name, bullet_prototype):
        self._prototypes[name] = bullet_prototype

    def unregister_prototype(self, name):
        if name in self._prototypes:
            del self._prototypes[name]

    def clone(self, name, new_coordinates):
        bullet = self._prototypes.get(name)
        if not bullet:
            raise ValueError(f"No prototype registered under name '{name}'")
        cloned = bullet.clone()
        cloned.set_coordinates(new_coordinates)
        return cloned

Copy
# main.py
from bullet import Bullet
from bullet_prototype_manager import BulletPrototypeManager

if __name__ == "__main__":
    manager = BulletPrototypeManager()

    # Register base bullets
    akm_bullet = Bullet("AKM", damage=50, speed=900, coordinates=(0, 0, 0))
    m416_bullet = Bullet("M416", damage=43, speed=880, coordinates=(0, 0, 0))

    manager.register_prototype("AKM", akm_bullet)
    manager.register_prototype("M416", m416_bullet)

    # Fire bullets (clone with new coordinates)
    fired1 = manager.clone("AKM", (10, 5, 2))
    fired2 = manager.clone("AKM", (12, 6, 2))
    fired3 = manager.clone("M416", (8, 3, 1))

    print(fired1)
    print(fired2)
    print(fired3)
# main.py
from bullet import Bullet
from bullet_prototype_manager import BulletPrototypeManager

if __name__ == "__main__":
    manager = BulletPrototypeManager()

    # Register base bullets
    akm_bullet = Bullet("AKM", damage=50, speed=900, coordinates=(0, 0, 0))
    m416_bullet = Bullet("M416", damage=43, speed=880, coordinates=(0, 0, 0))

    manager.register_prototype("AKM", akm_bullet)
    manager.register_prototype("M416", m416_bullet)

    # Fire bullets (clone with new coordinates)
    fired1 = manager.clone("AKM", (10, 5, 2))
    fired2 = manager.clone("AKM", (12, 6, 2))
    fired3 = manager.clone("M416", (8, 3, 1))

    print(fired1)
    print(fired2)
    print(fired3)

Output:

Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (10, 5, 2))
Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (12, 6, 2))
Bullet(M416, Damage: 43, Speed: 880, Coordinates: (8, 3, 1))

Summary:

• Avoids expensive object creation by cloning prototypes.
• Ideal for high-frequency or performance-critical object usage (e.g., bullets, particles, enemies in games).
• Ensures consistent configuration and fast instantiation.
• Reduces code duplication and supports flexible object creation.

    m416_bullet = Bullet("M416", damage=43, speed=880, coordinates=(0, 0, 0))

    manager.register_prototype("AKM", akm_bullet)
    manager.register_prototype("M416", m416_bullet)

    **Fire bullets (clone with new coordinates)**
    fired1 = manager.clone("AKM", (10, 5, 2))
    fired2 = manager.clone("AKM", (12, 6, 2))
    fired3 = manager.clone("M416", (8, 3, 1))

    print(fired1)
    print(fired2)
    print(fired3)

Output

Copy
Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (10, 5, 2))
Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (12, 6, 2))
Bullet(M416, Damage: 43, Speed: 880, Coordinates: (8, 3, 1))
Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (10, 5, 2))
Bullet(AKM, Damage: 50, Speed: 900, Coordinates: (12, 6, 2))
Bullet(M416, Damage: 43, Speed: 880, Coordinates: (8, 3, 1))

Summary

• Prototype Pattern avoids expensive object creation.
• Ideal for high-frequency object usage like game entities (bullets, particles, enemies).
• Ensures performance optimization and consistent object configuration.