Add Snake Game

GeeksForGeeks/issue/snake_game.py

@@ -0,0 +1,136 @@
+
+import turtle
+import random
+
+WIDTH = 500
+HEIGHT = 500
+FOOD_SIZE = 10
+DELAY = 100  # milliseconds
+
+offsets = {
+    "up": (0, 20),
+    "down": (0, -20),
+    "left": (-20, 0),
+    "right": (20, 0)
+}
+
+def reset():
+    global snake, snake_direction, food_pos, pen
+    snake = [[0, 0], [0, 20], [0, 40], [0, 60], [0, 80]]
+    snake_direction = "up"
+    food_pos = get_random_food_pos()
+    food.goto(food_pos)
+    # screen.update() Only needed if we are fussed about drawing food before next call to `draw_snake()`.
+    move_snake()
+
+def move_snake():
+    global snake_direction
+
+    #  Next position for head of snake.
+    new_head = snake[-1].copy()
+    new_head[0] = snake[-1][0] + offsets[snake_direction][0]
+    new_head[1] = snake[-1][1] + offsets[snake_direction][1]
+
+    # Check self-collision
+    if new_head in snake[:-1]:  # Or collision with walls?
+        reset()
+    else:
+        # No self-collision so we can continue moving the snake.
+        snake.append(new_head)
+
+        # Check food collision
+        if not food_collision():
+            snake.pop(0)  # Keep the snake the same length unless fed.
+
+        #  Allow screen wrapping
+        if snake[-1][0] > WIDTH / 2:
+            snake[-1][0] -= WIDTH
+        elif snake[-1][0] < - WIDTH / 2:
+            snake[-1][0] += WIDTH
+        elif snake[-1][1] > HEIGHT / 2:
+            snake[-1][1] -= HEIGHT
+        elif snake[-1][1] < -HEIGHT / 2:
+            snake[-1][1] += HEIGHT
+
+        # Clear previous snake stamps
+        pen.clearstamps()
+
+        # Draw snake
+        for segment in snake:
+            pen.goto(segment[0], segment[1])
+            pen.stamp()
+
+        # Refresh screen
+        screen.update()
+
+        # Rinse and repeat
+        turtle.ontimer(move_snake, DELAY)
+
+def food_collision():
+    global food_pos
+    if get_distance(snake[-1], food_pos) < 20:
+        food_pos = get_random_food_pos()
+        food.goto(food_pos)
+        return True
+    return False
+
+def get_random_food_pos():
+    x = random.randint(- WIDTH / 2 + FOOD_SIZE, WIDTH / 2 - FOOD_SIZE)
+    y = random.randint(- HEIGHT / 2 + FOOD_SIZE, HEIGHT / 2 - FOOD_SIZE)
+    return (x, y)
+
+def get_distance(pos1, pos2):
+    x1, y1 = pos1
+    x2, y2 = pos2
+    distance = ((y2 - y1) ** 2 + (x2 - x1) ** 2) ** 0.5
+    return distance
+
+def go_up():
+    global snake_direction
+    if snake_direction != "down":
+        snake_direction = "up"
+
+def go_right():
+    global snake_direction
+    if snake_direction != "left":
+        snake_direction = "right"
+
+def go_down():
+    global snake_direction
+    if snake_direction != "up":
+        snake_direction = "down"
+
+def go_left():
+    global snake_direction
+    if snake_direction != "right":
+        snake_direction = "left"
+
+# Screen
+screen = turtle.Screen()
+screen.setup(WIDTH, HEIGHT)
+screen.title("Snake")
+screen.bgcolor("green")
+screen.setup(500, 500)
+screen.tracer(0)
+
+# Pen
+pen = turtle.Turtle("square")
+pen.penup()
+
+# Food
+food = turtle.Turtle()
+food.shape("circle")
+food.color("red")
+food.shapesize(FOOD_SIZE / 20)  # Default size of turtle "square" shape is 20.
+food.penup()
+
+# Event handlers
+screen.listen()
+screen.onkey(go_up, "Up")
+screen.onkey(go_right, "Right")
+screen.onkey(go_down, "Down")
+screen.onkey(go_left, "Left")
+
+
+reset()
+turtle.done()