Kivy: better way to do timed events (dice rolling animation) - python

I am writing a yahtzee clone to teach myself Kivy (I'm still very new to Python and programming in general), and I'm having a little trouble figuring out how to best animate the dice rolling. This code works as intended, but I feel like I'm missing something conceptually. Is there a less involved or cleaner way to have a Clock event happen for a set period of time?
This is what I currently have:
The parent layout holds 5 dice as children widgets. The user clicks a button to roll them all using this method:
def roll_all_dice(self):
for dice in self.children:
Clock.schedule_interval(dice.roll, .1)
Clock.schedule_once(dice.roll_animation_callback, .5)
which, if I understand this correctly, schedules a roll every .1s, then .5s later, calls the roll_animation_callback, which stops the events.
Here are the relevant Dice methods:
def roll(self, *args):
'''changes the number of the die and updates the image'''
if self.state != "down":
self.number = randint(1,6)
self.source = self.get_image()
def get_image(self):
'''returns image path for each of the die's sides'''
if self.state == "down":
return "images/down_state/dice" + str(self.number) + ".png"
else:
return "images/up_state/dice" + str(self.number) + ".png"
def roll_animation_callback(self, *args):
'''turns off the dice rolling animation event'''
Clock.unschedule(self.roll)

This seems fine, using the Clock like this is normal.

Related

Raspberry Pi - Python - joystick

I am using Raspberry Pi.
while True:
if joystick.get_button(0) == 1:
print ("stop")
else
print ("start")
The purpose of this code is :
I want to interrupt some action while I press a button.
while running the code, it ignores me when I press the button and keep giving me "start". However, if I change the code to :
if joystick.get_button(0) == 0:
the program gives me "stop" at once. (0 is the default value of get_button(0), 1 means I press the button)
The cycle itself seems ok, so I would think that the problem is how your get_button() method acts. Be sure that it is returning the right value and that infinite loop and status checking are not running in the same thread.
Anyway, I would suggest you to use the Observer Pattern.
Basically, it allows you to create a reaction over your joystick button without using infinite loops.
The following code should fit your needs. Joystick class call methods from Player class every time the button is pressed, so every time Joystick change its state.
//OBSERVABLE OBJECT
class Joystick(object):
def __init__(self):
self._button = 0
self._observers = []
def get_button(self):
return self._button
def set_button(self, value):
for callback in self._observers:
callback(self._button)
def bind_to(self, callback):
self._observers.append(callback)
//OBSERVER OBJECT
class Player(object):
def __init__(self, controller):
self._state = 0; //1 - stop, 0 - play
self.controller.bind_to(self.change_state)
def change_state(self, new_state):
self_state = new_state
if(new_state == 0)
print 'play'
else
print 'stop'
This solution will print 'play' and 'stop' once, on every state change.
Then in your code you will create an observable instance:
joystick = new Joystick()
and pass it to an observer:
player = new Player(joystick)
in this way, when you launch your setter function:
joystick.set_button(0)
joystick will automatically change the status in player instance.

Trying to do animation but the program would close before it

I'm a beginner and was wondering if there was any way to finish the current animation before the program closes. Here is the sample of the code:
if playerHealth <= 0: # If the player dies
expl = Explosion(hit.rect.center, 'lg')
all_sprites.add(expl) # Show animation of him blowing up
running = False # End the game
Basically the running = False code would run before the animation(expl) starts. Is there a better way of showing this animation fully?
This sounds like a case for using a callback function. Pygame's animation class has the on_finished property which is intended to be assigned to a callback. The callback would be called once the animation is finished playing and would stop the game. Here's an example Explosion class.
class Explosion:
def __init__(self, rect, size, cb_func):
self.animate_explosion(cb_func)
...
def animate_explosion(self, cb_func):
# start animation here
...
# when animation finishes
self.on_finished = cb_func()
And then within your game logic you have something like the following:
def callback():
running = False
if playerHealth <= 0: # If the player dies
expl = Explosion(hit.rect.center, 'lg', callback())
all_sprites.add(expl) # Show animation of him blowing up
Probably You need more modifications, but one of them is:
if playerHealth <= 0 and not blowing_up_animation_started: # If the player dies
expl = Explosion(hit.rect.center, 'lg')
all_sprites.add(expl) # Show animation of him blowing up
blowing_up_animation_started = True
blowing_up_animation_finished = False
if blowing_up_animation_finished:
running = False # End the game

Python and tile based game: limiting player movement speed

I've been putting together an isometric tile-based RPG using Python and the Pyglet library. I've run into the following problem, however:
My player movement is based on positions on the three-dimensional array that consists of tiles. To limit movement speed, I use a global variable: TILE_TO_TILE_DELAY = 200.
TILE_TO_TILE_DELAY is supposed to be the amount of time in milliseconds it takes for the player to move from one tile to another. During this time, they should not be able to make a new movement.
The system I've been using is that I have a timer class, like this:
import time
def GetSystemTimeInMS(): #Return system time in milliseconds
systime = round((time.clock()*1000), 0)
return systime
class Timer:
def __init__(self,time):
#time = time for which the timer runs
self.time = time
self.start_time = 0
self.stop_time = 0
def StartTimer(self):
#start_time = time at which the timer was started
self.start_time = GetSystemTimeInMS()
self.stop_time = self.start_time + self.time
def TimerIsStopped(self):
if GetSystemTimeInMS() >= self.stop_time:
return True
else:
return False
The player class has a Timer object:
self.MoveTimer = Timer(TILE_TO_TILE_DELAY)
When the player presses the W-key, a function is called that checks for player.MoveTimer.TimerIsStopped(). If it returns True, it calls player.MoveTimer.StartTimer() and starts a new movement to the next position.
In the even loop, the update(dt) function is set to happen 30 times a second:
def update(dt):
if player.MoveTimer.TimerIsStopped()
player.UpdatePosition()
pyglet.clock.schedule_interval(update, 1/30)
Now, by my logic, update(dt) should check 30 times a second whether or not enough time has passed to warrant the player a new movement event. However, for some reason the player moves much faster at lower FPS.
When my FPS is around 30, the player moves much faster than in areas where there are less tile sprites, pumping the framerate to 60. In areas where FPS is high, the player indeed by my measurements moves almost twice as slowly.
I just cannot figure it out, nor did I find anything off the internet after a day of searching. Some help would be much appreciated.
Edit: The code that starts the MoveTimer:
def StartMovement(self, new_next_pos):
self.RequestedMovement = False
if self.GetCanMoveAgain():
self.SetNextPos(new_next_pos)
self.SetMoveDirection(self.GetDirection())
#Start the timer for the movement
self.MoveTimer.StartTimer()
self.SetIsMoving(True)
self.SetStartedMoving(True)
self.SetWalking(True)
self.SetNeedUpdate(True)
self.MOVE_EVENT_HANDLER.CreateMoveEvent()
GetCanMoveAgain() returns the value of player.can_move_again, which is set back to True by the UpdatePosition() in update(dt)
Alright, I fixed the problem, how ever I'm still unsure about what caused it. Maybe it was some sort of a rounding error with milliseconds, having to do with more checks being made to the clock when the FPS is higher. Anyways, the solution:
Instead of using the system clock, I decided to use Pyglet's own "dt" argument in their update functions:
The dt parameter gives the number of seconds (due to latency, load and timer inprecision, this might be slightly more or less than the requested interval).
The new timer looks like this:
class dtTimer: #A timer based on the dt-paremeter of the pyglet event loop
def __init__(self,time):
self.time = time
self.time_passed = 0
def StartTimer(self):
self.time_passed = 0
def UpdateTimer(self, dt):
self.time_passed += dt*1000
def GetTime(self):
return self.time
def GetTimePassed(self):
if not self.TimerIsStopped():
return self.time_passed
else:
return 0
def TimerIsStopped(self):
if self.time_passed > self.time:
return True
else:
return False
When the loop attempts to update the player's position, if the TimerIsStopped returns false, dt is simply added to the Timer's self.time_passed. This has fixed the issue: the time it takes for the player to move is now constant.
Thanks for looking at my issue.

Is this an optimal way of updating sprites in pygame?

Cutting through all the unrelated parts this is how I implemented it:
done=False
while(done==False)
#here goes some code for listening to the events
if (some condition fulfilled) then
screen.blit(background, [0,0])
screen.blit(some_sprite,[x,y])
elif (more conditions)
do something else
else
do even more stuff
pygame.display.flip()
Without the background update within this conditional statement this sprite doesn't get deleted, of course, os I get multiple copies on the screen. I have a strong suspicion this is by far not the optimal way of handling the situation, because blitting the image that doesn't change every time I need to do something else seems like a waste of resources.
I would appreciate any suggestions
Here's what I would recommend, based on personal experience. I built a tile-based game and over-engineered it a bit. My final solution looked a bit like this:
class Graphic(object):
def __init__(*some_args):
self.owner = which_object_owns_this_graphic
self.priority = some_int
# if more than one graphic are stacked on each other, which one to display?
self.surface = surface_to_draw_on
self.graphic = sprite_to_draw
#property
def x(self): return self.owner.x
#property
def y(self): return self.owner.y
def draw(self):
self.surface.blit(self.graphic, (self.x, self.y))
class Tile(object):
def __init__(*some_args):
self.x = x
self.y = y
self.graphic = some_default_Graphic_with_priority_minusone
self.contains = [self]
# list of objects that live here right now
#property
def topmost(self):
"""returns the graphic of the object with highest priority that is contained here"""
global_update_list = []
# anytime a tile is moved into or out of, place it here
Then in my event loop:
for tile in global_update_list:
tile.topmost.draw()
global_update_list = []
That prevented me from having to redraw the screen every time something moved, and I could just redraw the tile it moved out of and the tile it moved into.

How can I prevent my python game from reiterating and instead carry on?

I've made a simple game using pygame and livewires, where a sprite has to avoid falling mushrooms. The number of mushrooms falling at a certain time is meant to increase as the score increases. Here is what I mean:
from livewires import games,color
import random
games.init(screen_width=633,screen_height=479,fps=50)
class Stick_Man(games.Sprite):
def update(self):
self.x=games.mouse.x
if self.left<0:
self.left=0
if self.right>games.screen.width:
self.right=games.screen.width
self.check_collision()
def check_collision(self):
if self.overlapping_sprites:
self.over_message()
def over_message(self):
b=games.Message(value="Game Over", size=100, color=color.red,x=games.screen.width/2,y=games.screen.height/2,lifetime=250,after_death=games.screen.quit)
games.screen.add(b)
class Mushroom(games.Sprite):
score=0
start=200
score_required=100
level=1
total_score=0
speed=1
mushroom=games.load_image("mushroom.jpg")
x_position=random.randrange(640)
#staticmethod
def next_level():
indicate='Level ', + Mushroom.level, ' cleared'
message=games.Message(value=indicate,size=50,color=color.red,x=games.screen.width/2,y=games.screen.height/2, lifetime=150)
games.screen.add(message)
Mushroom().score_required+=50
Mushroom().score-=Mushroom.score_required
Mushroom().start-=150
Mushroom().speed+=5
Mushroom().level+=1
if Mushroom().start==20:
Mushroom().start+=10
def __init__(self):
super(Mushroom,self).__init__(image=Mushroom.mushroom,x=games.mouse.x,y=0)
def update(self):
self.dy=Mushroom.speed
self.check()
self.check2()
def check(self):
if self.bottom==games.screen.height:
self.destroy()
Mushroom.score+=50
Mushroom.total_score+=Mushroom.score
if Mushroom().score==Mushroom.score_required:
self.next_level()
def check2(self):
if self.top==Mushroom.start:
self.duplicate()
def duplicate(self):
new_mush=Mushroom()
games.screen.add(new_mush)
background_image=games.load_image("background.jpg", transparent=False)
games.screen.background=background_image
stickman_image=games.load_image("stickman.png", transparent=True)
stickman=Stick_Man(image=stickman_image,left=1,bottom=480)
games.screen.add(stickman)
games.mouse.is_visible=False
b=Mushroom()
c=Mushroom()
a=Mushroom()
games.screen.add(b)
games.screen.add(a)
games.screen.add(c)
games.screen.event_brab=True
games.screen.mainloop()
The code is pretty self explanatory and whenever one of the mushrooms is equal to start, then a new object is created thus meaning a new mushroom comes in. However, what happens is that code doesn't function properly a second time and the mushrooms don't get faster spawn much faster either. Also, when the game first starts, the minute the first mushroom hits the bottom it says level one cleared, when it should be after two mushrooms. The sprite is just a red mushroom and also a stickman which can be found on g images if you want to simulate.
So my question is how do i make the object's STATS carry on from where it left off whenever another mushroom appears and also display the message at the right time
Your problem is in all of the lines that look like this:
Mushroom().score_required+=50
There are a number of problems here, which all together add up to make this have no useful effect:
Mushroom() creates a new Mushroom instance (which goes away as soon as this line is done).
Assigning (including update-assigning) to an attribute through an instance always creates or updates an instance attribute, even if there was a class attribute of the same name.
The += operator doesn't mutate immutable values like integers in-place (because that would be impossible); a += b is effectively the same as a = a + b.*
So, when you put that together, what you're doing is creating a new value equal to Mushroom.score_required + 50, then assigning that value to a new instance attribute of a temporary instance (which immediately goes away). This has no effect on the class attribute, or on any of the other instances.
You have a related, but different, problem in the lines like this:
x_position=random.randrange(640)
Unless you want all of the mushrooms to have the same x_position, this should not be a class attribute, but an instance attribute, and you're going to run into all kinds of strange problems.
Storing game stats as class attributes of a random class is a strange thing to do. There are ways you could make that work, but there's no good reason to even try. Class attributes are useful for constants that all instances of the class might as well share, but they're not useful as a substitute for global variables.
A better design would be something like this:
class Game(object):
def __init__(self):
self.score = 0
self.start = 200
self.score_required = 100
self.level = 1
self.total_score = 0
def next_level(self):
indicate = 'Level ', + Mushroom.level, ' cleared'
message = games.Message(value=indicate, size=50, color=color.red,
x=games.screen.width/2, y=games.screen.height/2,
lifetime=150)
games.screen.add(message)
self.score_required += 50
self.score -= self.score_required
self.start -= 150
self.speed += 5
self.level += 1
if self.start == 20:
self.start += 10
def update_score(self, n):
game.score += n
game.total_score += game.score
if self.score == self.score_required:
self.next_level()
class Mushroom(games.Sprite):
mushroom=games.load_image("mushroom.jpg")
def __init__(self, game):
self.x_position=random.randrange(640)
self.game = game
super(Mushroom,self).__init__(image=Mushroom.mushroom,x=games.mouse.x,y=0)
def update(self):
self.dy=Mushroom.speed
self.check()
self.check2()
def check(self):
if self.bottom == games.screen.height:
self.destroy()
game.update_score(50)
def check2(self):
if self.top == Mushroom.start:
self.duplicate()
def duplicate(self):
games.screen.add(Mushroom(self.game))
game = Game()
games.screen.add(Mushroom(game))
games.screen.add(Mushroom(game))
games.screen.add(Mushroom(game))
games.screen.event_brab=True
* That's not completely true. In fact, a = a + b is equivalent to a = a.__add__(b), while a += b is equivalent to a = a.__iadd__(b) if such a method exists, falling back to __add__ only if it doesn't. For mutable objects like lists, this makes a big difference, because __iadd__ can change self in-place and then return it, meaning you end up assigning the same object back to a that was already there. But for immutable objects, there's no difference.

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