simple game with history, press S to save your position to a list of positions, and then B to go back in time
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
player.x = WIDTH/2
player.y = HEIGHT/2
history = []
def on_key_down(key):
speed = 3
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
if key == keys.S:
position = [player.x, player.y]
history.append(position)
print('append', history)
if key == keys.B and len(history) > 0:
last = history.pop()
player.x = last[0]
player.y = last[1]
print('pop', history)
def draw():
screen.fill('black')
player.draw()
pgzrun.go()
Two players, and more positions
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player1 = Actor("c1")
player2 = Actor('c2')
history = []
def on_key_down(key):
speed = 10
if key == keys.W:
player1.y-= speed
if key == keys.A:
player1.x-=speed
if key == keys.S:
player1.y += speed
if key == keys.D:
player1.x += speed
if key == keys.UP:
player2.y-= speed
if key == keys.LEFT:
player2.x-=speed
if key == keys.DOWN:
player2.y += speed
if key == keys.RIGHT:
player2.x += speed
if key == keys.F:
positions = [player1.x,player1.y,player2.x,player2.y]
history.append(positions)
print('push', history)
if key == keys.G:
if len(history) > 0:
positions = history.pop()
player1.x = positions[0]
player1.y = positions[1]
player2.x = positions[2]
player2.y = positions[3]
print('pop', history)
def draw():
screen.fill('black')
player1.draw()
player2.draw()
pgzrun.go()
More lists
a = ['h','w','e']
b = ['e','o','a']
c = ['l','r','r']
d = ['l','l','t']
e = ['o','d','h']
sum1 = ''
sum2 = ''
sum1 = a[0] + b[0] + c[0] + d[0] + e[0]
sum2 = a[1] + b[1] + c[1] + d[1] + e[1]
print(sum1)
print(sum2)
sum = []
for i in range(len(a)):
sum.append('')
sum[i] = a[i] + b[i] + c[i] + d[i] + e[i]
print(sum)
sum from the input
list = []
while True:
integer = int(input('enter a number: '))
list.append(integer)
sum = 0
for i in list:
sum += i
print(list, sum)
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
player.x = WIDTH/2
player.y = HEIGHT/2
things = []
def on_key_down(key):
speed = 10
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
if key == keys.F:
thing = Actor("flower")
thing.x = player.x
thing.y = player.y
things.append(thing)
if key == keys.R:
thing = Actor("rock")
thing.x = player.x
thing.y = player.y
things.append(thing)
def draw():
screen.fill('black')
player.draw()
for t in things:
t.draw()
pgzrun.go()
With a function, so we can add more keys faster and we dont duplicate that much code
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
player.x = WIDTH/2
player.y = HEIGHT/2
things = []
def place_thing(kind):
thing = Actor(kind)
thing.x = player.x
thing.y = player.y
things.append(thing)
def on_key_down(key):
speed = 15
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
if key == keys.F:
place_thing("flower")
if key == keys.R:
place_thing("rock")
if key == keys.K:
place_thing("c2")
def draw():
screen.fill('black')
player.draw()
for t in things:
t.draw()
pgzrun.go()
Now we can make a map, just add the kind of thing, its x and y position in a list and print it, after we are done building the map we can use it later
...
game_map = []
def place_thing(kind):
thing = Actor(kind)
thing.x = player.x
thing.y = player.y
things.append(thing)
game_map.append([kind, thing.x, thing.y])
print(game_map)
...
use the map:
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
player.x = WIDTH/2
player.y = HEIGHT/2
things = []
def place_thing(kind,x,y):
thing = Actor(kind)
thing.x = x
thing.y = y
things.append(thing)
def on_key_down(key):
speed = 15
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
def draw():
screen.fill('black')
player.draw()
for t in things:
t.draw()
game_map = [['rock', 100.0, 55.0], ['flower', 100.0, 85.0], ['c2', 100.0, 130.0], ['c2', 70.0, 130.0], ['c2', 55.0, 130.0], ['c2', 40.0, 130.0], ['c2', 25.0, 130.0], ['c2', 25.0, 100.0], ['c2', 25.0, 85.0], ['c2', 25.0, 70.0], ['c2', 25.0, 55.0], ['c2', 25.0, 40.0], ['c2', 25.0, 25.0], ['c2', 40.0, 25.0], ['c2', 55.0, 25.0], ['c2', 70.0, 25.0], ['c2', 85.0, 25.0], ['c2', 100.0, 25.0], ['c2', 115.0, 25.0], ['c2', 130.0, 25.0], ['c2', 145.0, 25.0], ['c2', 145.0, 40.0], ['c2', 145.0, 55.0], ['c2', 145.0, 70.0], ['c2', 145.0, 85.0], ['c2', 145.0, 100.0], ['c2', 145.0, 115.0], ['c2', 145.0, 130.0], ['c2', 130.0, 130.0], ['c2', 115.0, 130.0], ['c2', 100.0, 130.0], ['c2', 85.0, 130.0], ['c2', 25.0, 115.0]]
for g in game_map:
place_thing(g[0],g[1],g[2])
pgzrun.go()
Another way to do it, press S to print the list of things, and then paste it in the game[] list to use it, D deletes things where you stand, and U removes the last thing
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
things = []
game = []
for g in game:
t = Actor(g[0])
t.x = g[1]
t.y = g[2]
things.append(t)
def on_key_down(key):
speed = 10
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
if key == keys.F:
f = Actor("flower")
f.x = player.x
f.y = player.y
things.append(f)
if key == keys.R:
f = Actor("rock")
f.x = player.x
f.y = player.y
things.append(f)
if key == keys.U:
things.pop()
if key == keys.D:
collide = []
for t in things:
if player.colliderect(t):
collide.append(t)
for t in collide:
things.remove(t)
if key == keys.S:
positions = []
for t in things:
positions.append([t.image,t.x,t.y])
print(positions)
def draw():
screen.fill('black')
player.draw()
for t in things:
t.draw()
pgzrun.go()
Lets visualize the list, try to delete from the middle, and see how the indexes change.
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
player = Actor("c1")
things = []
def on_key_down(key):
speed = 10
if key == keys.UP:
player.y -= speed
if key == keys.DOWN:
player.y += speed
if key == keys.LEFT:
player.x -= speed
if key == keys.RIGHT:
player.x += speed
if key == keys.F:
f = Actor("flower")
f.x = player.x
f.y = player.y
things.append(f)
if key == keys.R:
f = Actor("rock")
f.x = player.x
f.y = player.y
things.append(f)
if key == keys.U:
things.pop()
if key == keys.D:
collide = []
for t in things:
if player.colliderect(t):
collide.append(t)
for t in collide:
things.remove(t)
def draw():
screen.fill('black')
player.draw()
for i in range(len(things)):
t = things[i]
t.draw()
screen.draw.text(str(i), color=(255,255,255), topleft=(t.x,t.y))
if i > 0:
p = things[i-1]
screen.draw.line((p.x,p.y), (t.x,t.y), (255,255,255))
pgzrun.go()
spend more time thinking about connecting previous and current elements from a list, think about how to do it the other way around, from current element to next:
# change this to go from t to the next element of things, instead from t to previous
for i in range(len(things)):
t = things[i]
...
if i > 0:
p = things[i-1]
...
This day is more about reading than writing, those are few different examples you can use
don't let the zombie flowers overrun you, smash them with rocks
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
game_over = False
elf = Actor("c1")
elf.x = WIDTH/2
elf.y = HEIGHT-20
flowers = []
rocks = []
game_area = Rect((0, 0), (WIDTH, HEIGHT-40))
def add_one_row():
lastY = 0
if len(flowers) > 0:
f = flowers[len(flowers)-1]
lastY = f.y
for i in range(20, WIDTH-10, 20):
f = Actor("flower")
f.x = i
f.y = lastY + 10
flowers.append(f)
def rock_out_of_screen():
if len(rocks) > 0:
rocks.pop(0)
def on_key_down(key):
speed = 10
if key == keys.LEFT:
elf.x -= speed
if key == keys.RIGHT:
elf.x += speed
if key == keys.SPACE:
rock = Actor("rock")
rock.x = elf.x
rock.y = elf.y - 20
animate(rock,pos=(rock.x, -100), on_finished=rock_out_of_screen)
rocks.append(rock)
def update():
global game_over
hit = []
for b in rocks:
for f in flowers:
if b.colliderect(f) and random.randint(0,10) > 7:
hit.append(f)
for h in hit:
flowers.remove(h)
for f in flowers:
if not f.colliderect(game_area):
game_over = True
def draw():
if game_over:
screen.draw.text("GAME OVER", color="white", topleft=(10,10))
else:
screen.fill('black')
elf.draw()
for f in flowers:
f.draw()
for r in rocks:
r.draw()
screen.draw.rect(game_area, (200, 0, 0))
add_one_row()
clock.schedule_interval(add_one_row, 5)
pgzrun.go()
import turtle as t
size = 10
t.pensize(size)
t.left(45)
t.forward(90)
t.circle(45,extent=180)
t.right(90)
t.circle(45,extent=180)
t.forward(90)
t.penup()
t.goto(-35,-35)
t.pendown()
t.write('i love python')
t.penup()
import turtle as t
import datetime
import time
def deg(h,m,s):
hDeg=(h*3600+m*60+s)/(3600*12)*360
mDeg=(m*60+s)/3600*360
sDeg=360/60*s
return (90+hDeg,90+mDeg,90+sDeg)
def show(h, size):
(hDeg,m,s) = deg(h,0,0)
t.penup()
t.goto(0, size)
t.pencolor('white')
t.setheading(hDeg)
t.forward(size)
t.write(str(h))
def klok(size, h, m, s):
t.reset()
(hDeg,mDeg,sDeg) = deg(h,m,s)
t.pendown()
t.pensize(7)
t.bgcolor('black')
t.pencolor('lime')
t.circle(size)
t.penup()
t.goto(0, size)
t.setheading(hDeg)
t.pendown()
t.pencolor('springgreen')
t.forward(size/3)
t.penup()
t.goto(0, size)
t.setheading(mDeg)
t.pendown()
t.pencolor('lawngreen')
t.forward(size/2)
t.penup()
t.pencolor('cyan')
t.goto(0, size)
t.setheading(sDeg)
t.pendown()
t.forward(size-25)
t.penup()
size = 150
while True:
now = datetime.datetime.now()
klok(size,now.hour, now.minute, now.second)
for h in range(1, 13):
show(h,size)
time.sleep(10)
Just one rock that hits the zombies above you
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
game_over = False
elf = Actor("c1")
elf.x = WIDTH/2
elf.y = HEIGHT-20
rock = Actor("rock")
rock.x = elf.x + 10
rock.y = elf.y - 20
flowers = []
def add_one_row():
lastY = 0
if len(flowers) > 0:
f = flowers[len(flowers)-1]
lastY = f.y
for i in range(20, WIDTH-10, 20):
f = Actor("flower")
f.x = i
f.y = lastY + 10
flowers.append(f)
def on_key_down(key):
speed = 10
if key == keys.LEFT:
elf.x -= speed
if key == keys.RIGHT:
elf.x += speed
if key == keys.UP:
elf.y -= speed
if key == keys.DOWN:
elf.y += speed
def update():
global game_over
hit = []
for f in flowers:
if rock.colliderect(f) and random.randint(0,10) > 7:
hit.append(f)
for h in hit:
flowers.remove(h)
rock.x -= 1
if rock.x < elf.x - 10:
rock.x = elf.x + 10
rock.y = elf.y - 20
def draw():
screen.fill('black')
elf.draw()
rock.draw()
for f in flowers:
f.draw()
add_one_row()
clock.schedule_interval(add_one_row, 5)
pgzrun.go()
SNAKE
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
snake = Actor("c1")
snake.x = WIDTH/2
snake.y = HEIGHT-20
apple = Actor("flower")
apple.x = WIDTH/2
apple.y = HEIGHT/2
snake_size = 20
snake_speed = 1
steps = []
direction = "up"
step_size = 1
game_over = False
game_area = Rect(0,0,WIDTH,HEIGHT)
def on_key_down(key):
global direction
if key == keys.LEFT:
direction = "left"
if key == keys.RIGHT:
direction = "right"
if key == keys.UP:
direction = "up"
if key == keys.DOWN:
direction = "down"
def update():
global snake_size, game_over, snake_speed, steps
s = Actor("snake")
s.x = snake.x
s.y = snake.y
steps.append(s)
if len(steps) > snake_size:
steps = steps[-snake_size:]
if direction == "left":
snake.x -= step_size
if direction == "right":
snake.x += step_size
if direction == "up":
snake.y -= step_size
if direction == "down":
snake.y += step_size
if snake.colliderect(apple):
apple.x = random.randint(0,WIDTH)
apple.y = random.randint(0,HEIGHT)
snake_size += step_size * 10
if not snake.colliderect(game_area):
game_over = True
def draw():
screen.fill('black')
if game_over:
screen.draw.text("GAME OVER", color="white", topleft=(10,10))
else:
screen.draw.rect(game_area, (255,0,0))
for s in steps:
s.draw()
snake.draw()
apple.draw()
pgzrun.go()
There are few key moments to emphasize, but the most important one is steps = steps[-snake_size:].
Try this in IDLE:
x = [1,2,3,4]
print(x[-1])
It will print '4', so in python you can get elements from the back of the list, just as easily as the front, try x[-2], now try to get multiple elements from a list, y = x[0:2], it will make new list [1,2], it is a bit like this code:
x = [1,2,3,4]
y = []
for i in range(0,2):
y.append(x[i])
Now you can also ask python to give you the first 2 elements by saying x[0:2] or you can ask it for the elements after the second one by doing x[2:len(x)], you can omit 0 and len(x) so it is a bit shorter, x[:2] and x[2:]. Sometimes you want the last 2 elements, to do that just say x[-2:len(x)] or x[-2:] and that's how we are getting the last snake_size elements of the steps list.
Again, x[-2:len(x)] just means from -2 elements from the end if the list, until the end of the list. It looks scary though.
Similar to this code:
x = [1,2,3,4]
y = []
for i in range(len(x)-2,len(x)):
y.append(x[i])
Its File time!
First lets make a new file, called day-87.txt and we will open it in "w" mode, which means "write", so once we do f.write it will start from the beginning of the file, we can use "a" (for append) mode as well that would continue appending to the end of the file
f = open("day-87.txt", "w")
while True:
a = input("what do you want to write: ")
if a == "quit":
break
f.write(a + "\n")
f.close()
Now you can open day-87.txt with Notepad or some other text editor and see what you wrote.
It is important to remember this pattern
- Open
- Read or Write
- Read or Write
- Read or Write
- Read or Write
- ...
- Close
lets see how you read a file:
f = open("day-87.txt", "r")
data = f.read()
print(data)
Make a game that persists the player position.
import pgzrun
import random
HEIGHT = 200
WIDTH = 200
elf = Actor("c1")
elf.x = WIDTH/2
elf.y = HEIGHT-20
try:
x = open("day-87-x.txt", "r")
elf.x = float(x.read())
x.close()
y = open("day-87-y.txt", "r")
elf.y = float(y.read())
y.close()
except IOError:
pass
def on_key_down(key):
speed = 10
if key == keys.LEFT:
elf.x -= speed
if key == keys.RIGHT:
elf.x += speed
if key == keys.UP:
elf.y -= speed
if key == keys.DOWN:
elf.y += speed
if key == keys.S:
x = open("day-87-x.txt", "w")
x.write(str(elf.x))
x.close()
y = open("day-87-y.txt", "w")
y.write(str(elf.y))
y.close()
def draw():
screen.fill('black')
elf.draw()
pgzrun.go()
open day-87-x.txt and day-87-y.txt to see the positions of X and Y of the elf after you press S.
One other patter you will see is:
try:
try to do something
except some error:
handle error
There are many many things that could go wrong when you write to or read a file, for example when you read the file might not be created, or you might have no access to read it, or when you write the disk might be full, and there is no more space.
In our example we don't check if our write fails, so if your disk is full the game will crash, but in the beginning we do check for IOError in case the reading fails, and it will if the files are not created yet the very first time you start the game and there is no save yet.
Reading exercise, a lot of unfamiliar code
from flask import Flask, redirect, request,make_response
import random
app = Flask(__name__)
tokens = {}
@app.route('/')
def index():
token = request.cookies.get('token')
if token in tokens:
response = make_response("""
welcome to the secure section of the website,
<a href="/logout">click here to logout
""")
return response
response = make_response("""
<html>
<form action="/login" method="post">
user: <input name="user">
pass: <input type="password" name="pass">
<input type="submit">
</form>
</html>
""")
return response
@app.route('/logout')
def logout():
token = request.cookies.get('token')
try:
del tokens[token]
except KeyError:
pass
response = make_response(redirect('/'))
response.set_cookie('token', '')
return response
@app.route('/login', methods = ['POST'])
def login():
user = request.form['user']
password = request.form['pass']
if user == "admin" and password == "123":
token = str(random.randint(0,10000000))
tokens[token] = "admin"
response = make_response(redirect('/'))
response.set_cookie('token', token)
return response
else:
return "access denied"
if __name__ == "__main__":
app.run(host="127.0.0.1",port=8000,debug=True)
start the script, see what it does, try to debug how tokens changes. Inspect your cookies, try to hack it, login from private mode and steal the cookie from the console.