class Snake(object):
"""This class draws and operates the line for Snake game"""
def __init__(self, pen, food_pen):
"""Constructor for Square class. This funcion is called upon
initialization. It saves a turtle object as a class member,
start line length to 5, creates list of Squares, set direction
to 'r', default speed to 1, creates food for snake and creates
snake itself.
Parameters
----------
pen : turtle
Turtle object that will draw the square
food_pen : turtle
Turtle object that will draw the food
Returns
-------
None
"""
self.speed = 1
self.snake = []
self.direction = 'r'
self.length = 5
self.pen = pen
self.food_pen = food_pen
# creating initial snake
for i in range(self.length):
square = Square(self.pen)
square.set_square(i*-square.size, square.size)
self.snake.append(square)
self.food = Food(self.food_pen)
self.food.create_food()
def set_direction(self,value):
"""Change direction of the snake. Possible directions are:
`r`, `l`, `u`, `d`.
Parameters
----------
value : str
New snake direction
Returns
-------
None
"""
if self.direction == 'r' and value != 'l':
self.direction = value
if self.direction == 'l' and value != 'r':
self.direction = value
if self.direction == 'u' and value != 'd':
self.direction = value
if self.direction == 'd' and value != 'u':
self.direction = value
def self_collision(self):
"""Check snake collision with itself.
Parameters
----------
None
Returns
-------
collision
bool
"""
collision = False
for sqr in range(1,len(self.snake)):
if self.snake[0].x == self.snake[sqr].x and self.snake[0].y == self.snake[sqr].y:
collision = True
return collision
def border_collision(self):
"""Check snake collision with border.
Parameters
----------
None
Returns
-------
collision
bool
"""
collision = False
if self.snake[0].x > 200 or self.snake[0].x < -200:
collision = True
elif self.snake[0].y > 200 or self.snake[0].y < -200:
collision = True
return collision
def draw_snake(self):
"""Draw snake.
Parameters
----------
None
Returns
-------
None
"""
for i in range(len(self.snake)):
self.snake[i].draw(self.snake[i].x,self.snake[i].y, "black")
def move_snake(self):
"""Move snake.
Parameters
----------
None
Returns
-------
None
"""
old_x = self.snake[0].x
old_y = self.snake[0].y
for square in range(len(self.snake)):
if square == 0:
old_x = self.snake[square].x
if self.direction == "r":
self.snake[square].x += self.snake[0].size
elif self.direction == "l":
self.snake[square].x -= self.snake[0].size
elif self.direction == "u":
self.snake[square].y += self.snake[0].size
elif self.direction == "d":
self.snake[square].y -= self.snake[0].size
else:
old_x, self.snake[square].x = self.snake[square].x, old_x
old_y, self.snake[square].y = self.snake[square].y, old_y
def food_collision(self,x,y):
"""Check collision with food.
Parameters
----------
x
Horisontal Coordinate
y
Vertical Coordinate
Returns
-------
collision
bool
"""
collision = False
# food_collision
if self.food.collision_with_food(x,y):
# add square to the snake
square = Square(self.pen)
square.set_square(x,y)
self.snake.append(square)
# make snake move faster
self.increase_speed()
# make more food
self.food.create_food()
self.food.draw_food()
# increase the length of the snake
self.length += 1
collision = True
return collision
def increase_speed(self):
"""Incerease speed of the snake.
Parameters
----------
None
Returns
-------
None
"""
self.speed += 1
