qubyt
Reputation: 25
Pygame only advances on keypress
I imagine this is a simple fix and have seen similar questions, but this is really frustrating me. Basically when you run the game, it only advances the simulation on a keypress, and not at a set framerate.
The main code is:
pg.init()
clock = pg.time.Clock()
FPS = 10
# ...
Game = Control()
while not Game.done:
Game.main_loop()
pg.display.update()
clock.tick(FPS)
pg.quit()
and the event handler method - within the Control class - is:
def event_handler(self):
for event in pg.event.get():
if event.type == pg.QUIT:
self.done = True
elif event.type == pg.KEYDOWN:
self.scene.process_event(event)
The weird thing to me is that, at the bottom of the pastebin, is my old testing code that is not done with classes for Scenes/Control. However, to my eye it should work exactly the same. I've tried putting in the clock both in and out of the Control class to no avail.
Any help (and general tips!) greatly appreciated.
Thanks
Upvotes: 0
Views: 71
Answers (1)
furas
Reputation: 142641
process_event() should only change variables which depend on events but it shouldn't update other values which should be updated in every frame. You have to move some elements to new method update() and execute it in every loop.
More or less
class Scene:
def process_event(self, event):
pass
def update(self):
pass
class GamePlayState(Scene):
def process_event(self, event):
self.snake.get_key(event)
def update(self):
self.snake.update()
self.snake.food_check(self.apple)
self.snake.collision_check()
if self.snake.alive == False:
print("GAME OVER")
print(self.snake.points)
self.done = True
class Control:
def update(self):
self.scene.update()
def main_loop(self):
self.event_handler()
self.update()
self.scene_checker()
self.draw()
Full working code
import pygame as pg
import sys
import random
import queue
# TODO: Walls, queue for keypress, scene stuff, 2 player, difficulty(?)
""" ######################
PREAMBLE
###################### """
""" Dictionaries for direction/velocity mapping - stolen from https://github.com/Mekire """
DIRECT_DICT = {"left" : (-1, 0), "right" : (1, 0),
"up" : (0,-1), "down" : (0, 1)}
KEY_MAPPING = {pg.K_LEFT : "left", pg.K_RIGHT : "right",
pg.K_UP : "up", pg.K_DOWN : "down"}
OPPOSITES = {"left" : "right", "right" : "left",
"up" : "down", "down" : "up"}
""" Colour Mapping """
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
DARK_GREY = (70, 70, 70)
GREY = (211, 211, 211)
GREEN = (0, 255, 0)
RED = (255, 0, 0)
COLOUR_MAP = {"snake": GREEN, "apple": RED, "wall": BLACK, "surface": GREY, "background": DARK_GREY }
""" ################
CLASSES
################ """
""" ####################### Object Classes ########################## """
class Square:
""" All other objects in the game will be built up from this """
def __init__(self, pos, colour, length):
self.xi, self.yi = pos # i for index, p for pixel
self.colour = colour
self.length = length
def display(self):
xp, yp = self.sq_to_pixs(self.xi, self.yi) # (x = left side, y = top edge)
pg.draw.rect(screen, self.colour, (xp, yp, self.length, self.length), 0)
def sq_to_pixs(self, x, y):
# Converts index of square to pixel coords
px = (x+1)*(2*MARGIN + SQUARE_SIZE) - MARGIN - SQUARE_SIZE
py = (y+1)*(2*MARGIN + SQUARE_SIZE) - MARGIN
return (px, py)
def index_coords(self): # TODO - remove for direct ref?
return (self.xi, self.yi)
class Arena:
""" A grid within which the game takes place """
def __init__(self, size, square_length, colour):
self.size = size # i.e. number of squares = size**2 for square arena
self.length = square_length # i.e. per square dimension
self.colour = colour
self.squares = [ [] for i in range(self.size) ]
for y in range(self.size):
for x in range(self.size):
self.squares[y].append(Square((x,y), self.colour, self.length))
def display(self):
for y in self.squares:
for square in y:
square.display()
class Snake:
""" Class for the agent(s) """
def __init__(self, pos, colour, square_length):
self.xi, self.yi = pos
self.colour = colour
self.size = 3
self.length = square_length
self.direction = "right"
self.direction_queue = queue.Queue(4) # TODO
self.points = 0
self.growing = False
self.alive = True
self.squares = []
for x in range(self.size): # horizontal initial orientation
self.squares.append(Square((self.xi - x, self.yi), self.colour, self.length))
def display(self):
for square in self.squares:
square.display()
def food_check(self, apple):
if self.squares[0].index_coords() == apple.square.index_coords():
self.growing = True
self.points += apple.points_value
apple.respawn([self])
def collision_check(self, walls = None):
xh, yh = self.squares[0].index_coords()
body = self.squares[-1:0:-1] # going backwards thru array as forwards [0:-1:1] didnt work...
def _collide(obstacles):
for sq in obstacles:
_x, _y = sq.index_coords()
if (_x == xh) and (_y == yh):
self.alive = False
_collide(body)
if walls is not None:
_collide(walls)
def update(self):
# Add new head based on velocity and old head
velocity = DIRECT_DICT[self.direction]
head_coords = [ (self.squares[0].index_coords()[i] + velocity[i]) for i in (0,1) ]
# Wrap around screen if reach the end
for i in (0, 1):
if head_coords[i] < 0:
head_coords[i] = SQUARES_PER_ARENA_SIDE - 1
elif head_coords[i] > SQUARES_PER_ARENA_SIDE - 1:
head_coords[i] = 0
self.squares.insert(0, Square(head_coords, self.colour, self.length))
if self.growing:
self.growing = False
else:
del self.squares[-1]
"""
def queue_key_press(self, key):
for keys in KEY_MAPPING:
if key in keys:
try:
self.direction_queue.put(KEY_MAPPING[keys], block=False)
break
except queue.Full:
pass
"""
class Player(Snake):
""" Human controlled snake via arrow keys """
def __init__(self, pos, colour, size):
Snake.__init__(self, pos, colour, size)
def get_key(self, event):
if event.type == pg.KEYDOWN and event.key in KEY_MAPPING:
new_direction = KEY_MAPPING[event.key]
if new_direction != OPPOSITES[self.direction]:
self.direction = new_direction
class Apple:
""" Food our (veggie) snake is greedily after """
def __init__(self, colour, length, points_value, snake):
self.colour = colour
self.length = length
self.xi, self.yi = self._rand_coords()
self.points_value = points_value
self.square = Square((self.xi, self.yi), self.colour, self.length)
def _rand_coords(self):
rand_num = lambda x: random.randint(0, x)
_x = rand_num(SQUARES_PER_ARENA_SIDE-1)
_y = rand_num(SQUARES_PER_ARENA_SIDE-1)
return _x, _y
def respawn(self, obstacles):
_x, _y = self._rand_coords()
for ob in obstacles:
for sq in ob.squares:
while sq.index_coords() == (_x, _y):
_x, _y = self._rand_coords()
self.square.xi, self.square.yi = _x, _y
def display(self):
self.square.display()
""" ################ SCENES ####################### """
class Scene:
""" Overload most of this - barebones structure
A bit pointless in current state but easily expanded """
def __init__(self):
self.done = False
def when_activated(self):
pass
def reset(self):
self.done = False
def render(self):
pass
def process_event(self, event):
pass
def update(self):
pass
class StartUp(Scene):
def __init__(self):
Scene.__init__(self)
def render(self):
# test placeholder
pass
def when_activated(self):
print("Press any key to continue")
def process_event(self, event):
if event.type == pg.KEYDOWN:
self.done = True
class GamePlayState(Scene):
def __init__(self):
Scene.__init__(self)
self.arena = Arena(SQUARES_PER_ARENA_SIDE, SQUARE_SIZE, COLOUR_MAP["surface"])
self.snake = Player(SNAKE_START, COLOUR_MAP["snake"], SQUARE_SIZE)
self.apple = Apple(COLOUR_MAP["apple"], SQUARE_SIZE, 1, self.snake)
self.font = pg.font.SysFont("courier new", 50)
def render(self):
screen.fill(COLOUR_MAP["background"])
self.arena.display()
self.apple.display()
self.snake.display()
text = self.font.render(str(self.snake.points), True, [255,255,255])
screen.blit(text, (500, 400))
def process_event(self, event):
self.snake.get_key(event)
def update(self):
self.snake.update()
self.snake.food_check(self.apple)
self.snake.collision_check()
if self.snake.alive == False:
print("GAME OVER")
print(self.snake.points)
self.done = True
""" ################## CONTROL CLASS #########################"""
class Control:
def __init__(self):
#self.clock = pg.time.Clock()
#self.fps = FPS
self.done = False
self.scene_array = [StartUp(), GamePlayState()]
self.scene_index = 0 # dirty way whilst dict method needs tinkering
#self.scene_dict = {"START": StartUp(), "GAME": GamePlayState()} #TODO
self.scene = self.scene_array[self.scene_index]
#self.scene = self.scene_dict["START"]
self.scene.when_activated()
def event_handler(self):
for event in pg.event.get():
if event.type == pg.QUIT:
self.done = True
elif event.type == pg.KEYDOWN:
self.scene.process_event(event)
def scene_checker(self):
if self.scene.done:
self.scene.reset() # for reuse - TODO
self.scene_index = (self.scene_index + 1) % len(self.scene_array)
self.scene = self.scene_array[self.scene_index]
self.scene.when_activated()
#self.scene = self.scene_dict[self.scene.next]
def update(self):
self.scene.update()
def draw(self):
self.scene.render()
def main_loop(self):
self.event_handler()
self.update()
self.scene_checker()
self.draw()
""" ################ RUN GAME ################ """
""" Game paramaters """
SQUARE_SIZE = 20 # pixels
SQUARES_PER_ARENA_SIDE = 20 # squares
MARGIN = 2 # pixels
SNAKE_START = (int(SQUARES_PER_ARENA_SIDE/2), int(SQUARES_PER_ARENA_SIDE/2)) # square coords
pg.init()
clock = pg.time.Clock()
# Square.display() and a few others need a direct reference to "screen" TODO implement better
w, h = 620, 620
SCREEN_SIZE = [w, h]
FPS = 10
screen = pg.display.set_mode(SCREEN_SIZE)
Game = Control()
while not Game.done:
Game.main_loop()
pg.display.update()
clock.tick(FPS)
pg.quit()
Upvotes: 1