[pygame] circular movement in pygame

[diliup gabadamudalige <diliupg@xxxxxxxxx>]

Looking at the code on this page lines 47 & 48

http://programarcadegames.com/python_examples/show_file.php?file=sprite_circle_movement.py

is there a way to doÂ

self.rect.x += some value

self.rect.y += some value

rather than

self.rect.x = self.radius * math.sin(self.angle) + self.center_x

self.rect.y = self.radius * math.cos(self.angle) + self.center_y




?

I tired it in the code attached and strangely it works ok but only OUTSIDE THE class. When I implement the exact code in a class it does something weird. I can't find where I have gone wrong.

Please help.

Many thanks in advance.

Diliup Gabadamudalige

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import sys, os, pygame, itertools
from math import sin,cos,pi, radians
from pygame.locals import *

os.environ['SDL_VIDEO_WINDOW_POS'] = "%d,%d" % (50,50) #Set window position

pygame.init()
clock = pygame.time.Clock()
FPS = 1000

SCREENW = 800   #screen width
SCREENH = 740   #screen height

BLACK = (0, 0, 0)
BLUE = (0, 0, 255)
ORANGE = (128, 100, 30)
FONT1= "Cookie-Regular.ttf"

SCREEN = pygame.display.set_mode((SCREENW, SCREENH), 0, 32) #display screen
clock = pygame.time.Clock()

#-------------------------------------------------------------------------------
def maketext(msg,fontsize, colour = ORANGE, font = FONT1):
    mafont = pygame.font.Font(font, fontsize)
    matext = mafont.render(msg, True, colour)
    matext = matext.convert_alpha()
    return matext

#-------------------------------------------------------------------------------
def print_info():
    """"""
    textcos = maketext(str(round(obj.rect.x, 2)) + "   " + str(round(obj.rect.y, 2)), 30)
    SCREEN.blit(textcos, (obj.rect.x, obj.rect.y + 30))

#-------------------------------------------------------------------------------
class object_factory(pygame.sprite.Sprite):

    def __init__(self, imagelist, xpos = 0, ypos = 0, speedx = 0, speedy = 0, value = 0):
        """Constructor"""
        pygame.sprite.Sprite.__init__(self)
        self.name = ""
        self.frame = 0
        self.imagelist = imagelist
        self.image = imagelist[self.frame]
        self.mask = pygame.mask.from_surface(self.image) # pixelmask
        self.rect = self.image.get_rect()
        self.rect.x = xpos
        self.rect.y = ypos
        self.speedx = speedx
        self.speedy = speedy
        self.timer = 0
        self.timerlimit = 10

        #----------------------------------------------------------------------
    def move(self):  # wallsprites, Herosprite, looptime
        self.rect.x += self.speedx
        self.rect.y += self.speedy

    #----------------------------------------------------------------------
    def update(self):
        """"""
        self.image = self.imagelist[self.frame]
        if self.timer >= self.timerlimit:
            self.frame += 1
            if self.frame >= len(self.imagelist):
                self.frame = 0
            self.timer = 0
        self.timer += 1

plat = pygame.image.load("plt0.png").convert_alpha()
star = pygame.image.load("gemp0.png").convert_alpha()
box = pygame.image.load("crateB.png").convert_alpha()

platforms = pygame.sprite.Group()
boxes = pygame.sprite.Group()