Screensaver loading screen demo showing vectors in pygame

screensaver.py

# Libraries to use. Pygame and system library
import pygame, sys, random, time, math
from pygame.locals import *

#-----------------------------------------------
# INITIALISATION
#-----------------------------------------------

# Set up pygame
pygame.init()

# Set up the window size and title text
SCREEN_WIDTH = 800
SCREEN_HEIGHT = 500
window = pygame.display.set_mode((SCREEN_WIDTH,SCREEN_HEIGHT))
pygame.display.set_caption("Hello Pygame")

#load images
sanic = pygame.image.load("sanic.png")

#sanic position
randX = random.randint(0,SCREEN_WIDTH-sanic.get_width())
randY = random.randint(0,SCREEN_HEIGHT-sanic.get_height())
pos = (randX, randY)
speed = 10
randVelX = random.randint(-10,10)
randVelY = random.randint(-10,10)
mag = math.sqrt(randVelX*randVelX+randVelY*randVelY)
direction = (randVelX/mag, randVelY/mag)
velocity = (direction[0]*speed, direction[1]*speed)

#-----------------------------------------------
# THE GAME LOOP
#-----------------------------------------------
while True:
    
    #-----------------------------------------------
    # LOGIC
    #-----------------------------------------------

    # target
    if pygame.mouse.get_pressed()[0]:
        target = pygame.mouse.get_pos()
        diff = (target[0]-pos[0], target[1]-pos[1])
        mag = math.sqrt(diff[0]*diff[0]+diff[1]*diff[1])
        direction = (diff[0]/mag, diff[1]/mag)
        velocity = (direction[0]*speed, direction[1]*speed)

    # movement
    pos = (pos[0]+velocity[0],pos[1]+velocity[1])

    # bouncing
    if pos[0] < 0:
        pos = (0, pos[1])
        velocity = (-velocity[0], velocity[1])
    elif pos[0] > SCREEN_WIDTH - sanic.get_width():
        pos = (SCREEN_WIDTH - sanic.get_width(), pos[1])
        velocity = (-velocity[0], velocity[1])
    if pos[1] < 0:
        pos = (pos[0], 0)
        velocity = (velocity[0], -velocity[1])
    elif pos[1] > SCREEN_HEIGHT - sanic.get_height():
        pos = (pos[0], SCREEN_HEIGHT - sanic.get_height())
        velocity = (velocity[0], -velocity[1])

    
    #-----------------------------------------------
    # RENDER
    #-----------------------------------------------

    # Draw the background
    window.fill((97, 255, 231))

    # Draw objects
    window.blit(sanic, pos)
    
    # Put it all on the screen
    pygame.display.update()
    time.sleep(0.02)
    
    
    #-----------------------------------------------
    # EVENTS
    #-----------------------------------------------

    # check for events (user input)
    for event in pygame.event.get():

        #if they closed the window...
        if event.type == QUIT:

            #quit!
            pygame.quit()
            sys.exit()