Kostik Iln Crosshair Circular Boundary

import pygame
from pygame import Vector2, Rect
from pygame.locals import *

WHITE = 16777215
BLACK = 0

pygame.init()
PDR = Rect(0, 0, 1280, 720)
PDS = pygame.display.set_mode(PDR.size)

boundry_pos = Vector2(PDR.center)
boundry_radius = 200
crosshair_pos = Vector2(PDR.center)

exit_demo = False
while not exit_demo:
    for e in pygame.event.get():
        if e.type == KEYUP and e.key == K_ESCAPE:
            exit_demo = False

    crosshair_pos = Vector2(pygame.mouse.get_pos())
    distance = boundry_pos.distance_to(crosshair_pos)
    if distance >= boundry_radius:
        degrees = Vector2().angle_to(crosshair_pos - boundry_pos)
        crosshair_pos = Vector2(PDR.center) + Vector2(1, 0).rotate(degrees) * boundry_radius

    PDS.fill(BLACK)
    pygame.draw.circle(PDS, WHITE, PDR.center, boundry_radius, 2)
    pygame.draw.line(PDS, WHITE, crosshair_pos - (0, 25), crosshair_pos + (0, 25))
    pygame.draw.line(PDS, WHITE, crosshair_pos - (25, 0), crosshair_pos + (25, 0))
    pygame.display.update()

    pygame.time.Clock().tick(120)