[2021 Spring] CS61A Project 3: Ants Vs. SomeBees (Phase 1)
项目说明：https://inst.eecs.berkeley.edu/~cs61a/sp21/proj/ants/
蚂蚁大战蜜蜂 灵感来源：植物大战僵尸（Plants Vs. Zombies，PVZ）
Phase 1： https://www.cnblogs.com/ikventure/p/14986805.html
Phase 2： https://www.cnblogs.com/ikventure/p/14988467.html
Phase 3： https://www.cnblogs.com/ikventure/p/14992754.html
Phase 4： https://www.cnblogs.com/ikventure/p/14994734.html
效果展示： https://www.cnblogs.com/ikventure/p/15001093.html
游戏说明
游戏按轮次进行，每一轮中，新的蜜蜂都可能进入蚁群领地。然后，放置新的蚂蚁来保卫它们的领地。 最后，所有昆虫（蚂蚁，蜜蜂）都会采取单独的行动。蜜蜂沿着tunnel从右往左移动，遇到蚂蚁则攻击蚂蚁。不同类型的蚂蚁执行不同的动作，例如收集更多食物或向蜜蜂扔树叶。 当一只蜜蜂到达tunnel尽头或者摧毁了 QueenAnt（如果存在），你就输了；整个蜜蜂舰队都被打败，你就赢了；游戏结束。
核心概念和核心类都跟PVZ类似。
Phase 1: Basic gameplay
Problem 1 (1 pt)
Part A: 当前放置任一类型Ant都没有cost，基类Ant的food_cost为0。任务：根据表格的"Food cost"重写HarvesterAnt和ThrowerAnt的类属性。
| Class | Food Cost | Initial Health |
|---|---|---|
| HarvesterAnt | 2 | 1 |
| ThrowerAnt | 3 | 1 |
| Part B: 放置ant需要消耗食物，HarvesterAnt生产食物（类似PVZ向日葵） 任务：完成HarvesterAnt action方法。 | ||
| 代码： |
class HarvesterAnt(Ant):
"""HarvesterAnt produces 1 additional food per turn for the colony."""
name = 'Harvester'
implemented = True
# OVERRIDE CLASS ATTRIBUTES HERE
food_cost = 2
def action(self, gamestate):
"""Produce 1 additional food for the colony.
gamestate -- The GameState, used to access game state information.
"""
# BEGIN Problem 1
"*** YOUR CODE HERE ***"
gamestate.food += 1
# END Problem 1
class ThrowerAnt(Ant):
"""ThrowerAnt throws a leaf each turn at the nearest Bee in its range."""
name = 'Thrower'
implemented = True
damage = 1
# ADD/OVERRIDE CLASS ATTRIBUTES HERE
food_cost = 3
Problem 2 (2 pt)
任务：完成 Place.__init__记录入口entrance。
分析：类似链表结构，创建Place对象时，entrance为None；如果这个对象的exit不为None，将这个exit的entrance设置为这个对象。
代码：
class Place:
"""A Place holds insects and has an exit to another Place."""
def __init__(self, name, exit=None):
"""Create a Place with the given NAME and EXIT.
name -- A string; the name of this Place.
exit -- The Place reached by exiting this Place (may be None).
"""
self.name = name
self.exit = exit
self.bees = [] # A list of Bees
self.ant = None # An Ant
self.entrance = None # A Place
# Phase 1: Add an entrance to the exit
# BEGIN Problem 2
"*** YOUR CODE HERE ***"
if self.exit:
self.exit.entrance = self
# END Problem 2
Problem 3 (2 pt)
ThrowerAnt类似豌豆射手，需要根据nearest_bee方法确定攻击哪只蜜蜂(攻击身前且不在蜂巢中的蜜蜂)。
任务：修改nearest_bee让它返回最近的蜜蜂之一。
- 从豌豆射手ThrowerAnt的位置开始
- 对于每个place，如果其中有蜜蜂，则随机返回蜜蜂之一；如果没有蜜蜂，查找更前面的place
- 如果没有蜜蜂可以攻击，返回None
遍历豌豆射手身前的place时，由于self.place不会变，所以引入新参数next_place，place中没有蜜蜂，则赋值为下一个格子next_place.entrance，直到找到有蜜蜂的place或者到达蜂巢。
注意：phase 2中problem 4有新要求，要考虑ant的攻击距离，相应的problem 3部分会在phase 2进行修改。
class ThrowerAnt(Ant):
"""ThrowerAnt throws a leaf each turn at the nearest Bee in its range."""
name = 'Thrower'
implemented = True
damage = 1
# ADD/OVERRIDE CLASS ATTRIBUTES HERE
food_cost = 3
def nearest_bee(self, beehive):
"""Return the nearest Bee in a Place that is not the HIVE (beehive), connected to
the ThrowerAnt's Place by following entrances.
This method returns None if there is no such Bee (or none in range).
"""
# BEGIN Problem 3 and 4
# 不能改变ant的位置self.place
next_place = self.place
while not next_place.is_hive():
if next_place.bees:
return bee_selector(next_place.bees) # REPLACE THIS LINE
next_place = next_place.entrance
return None
# END Problem 3 and 4
