This is a class of a box that bounces around the screen. According to the code, you can assign the class by: box1 = box.Box( screen, (32,32), (1,1), THECOLORS["black"], THECOLORS["white"] ) First of all, I don't understand what __init__ does in the class. Secondly, how is the order of the parameters for the above code work? Does it find the order of the functions in the class and parse them automatically? Yes, I know near nothing about classes :D Thanks in advance for any help! (BTW code is from this page http://www.penzilla.net/tutorials/python/pygame/ )

import pygame
from pygame.locals import *

class Box:
    def __init__(self, screen, size, velocities, background, boxcolor):
        self.screen = screen
        screensize = self.screen.get_size()
        self.screenwidth = screensize[0]
        self.screenheight = screensize[1]
        # Position of Box on the Screen
        # Box will start roughly in the middle of the screen.
        self.x = screensize[0]/2
        self.y = screensize[1]/2
        self.width = size[0]
        self.height = size[1]
        # Velocity of the box
        self.vx = velocities[0]
        self.vy = velocities[1]
        self.bgcolor = background
        self.boxcolor = boxcolor
        self.rect = pygame.rect.Rect(self.x, self.y, self.width, self.height)

    def draw(self):
        # Erase the previous box
        pygame.draw.rect( self.screen, self.bgcolor, self.rect )
        # Update position or reverse direction
        # Check for collision with the sides:
        nx, ny = self.x + self.vx, self.y + self.vy
        bound_x = nx + self.width
        bound_y = ny + self.height
        if( (bound_x >= self.screenwidth) or
             (nx <= 0) ):
            self.vx *= -1 * 0.9 # Bounces decrease velocity slightly
        else:
            self.x = nx
        if( (bound_y >= self.screenheight) or
             (ny <= 0 ) ):
            self.vy *= -1 * 0.9
        else:
            self.y = ny
        # Draw the new box
        self.rect = pygame.rect.Rect(nx, ny, self.width, self.height)
        pygame.draw.rect( self.screen, self.boxcolor, self.rect )
        
        
    def setV(self,x,y):
        self.vx = x
        self.vy = y

    def setBackgroundColor(self, color):
        self.bgcolor=color
    def setBoxColor(self, color):
        self.boxcolor=color

Thanks great post!

What is the role of __init__(self) ?

Thanks for that grekster, I understand a lot better now :)