Pygame dessiner/sélectionner Cercle

Question

Je travaille sur un projet et j'ai besoin de créer un graphe de nœud.

C'est ce que j'ai fait jusqu'à présent (un écran et une fonction pour dessiner un cercle numéroté au clic de la souris) et maintenant je suis coincé.

Comment puis-je sélectionner un cercle après la création pour le déplacer?

import pygame 
WHITE =  (255, 255, 255) 
BLUE =  ( 0, 0, 255) 
GREEN =  ( 0, 255, 0) 
RED =  (255, 0, 0) 
TEXTCOLOR = ( 0, 0, 0) 
(width, height) = (800, 600) 
BASICFONTSIZE = 10 
count = 0 

running = True 


def getPos(): 
    pos = pygame.mouse.get_pos() 
    return (pos) 

def drawCircle(): 
    global count 
    pos = getPos() 
    radius = 20 
    pygame.draw.circle(screen, BLUE, pos, radius,7) 
    textSurf = BASICFONT.render(str(count), True, TEXTCOLOR) 
    textRect = textSurf.get_rect() 
    textRect.center = int(pos[0]),int(pos[1]) 
    screen.blit(textSurf, textRect) 
    count += 1 

def main(): 
    global running, screen, BASICFONT 

    pygame.init() 
    BASICFONT = pygame.font.Font('freesansbold.ttf', BASICFONTSIZE) 
    screen = pygame.display.set_mode((width, height)) 
    pygame.display.set_caption("TUFF") 
    screen.fill(WHITE) 
    pygame.display.update() 

    while running: 
     ev = pygame.event.get() 

     for event in ev: 

      if event.type == pygame.MOUSEBUTTONUP: 
       drawCircle() 
       pygame.display.update() 

      if event.type == pygame.QUIT: 
       running = False 


if __name__ == '__main__': 
    main() 

Answer 1

from random import randrange, choice 
import pygame 
import sys 
from pygame.locals import * 

snode = int(input("How manny nodes do you need? = ")) 
FR = 30 
SIZE = 640, 480 
BGCOLOR = (255,255,255) 
NODECOLOR = (255,0,170) 
NODESIZE = 25,25 
GRIDSPACING = 50 
MAXTRIES = 1000 
STARTINGNODES = snode 
TEXTCOLOR = (0,255,0) 
BASICFONTSIZE = 20 


class Graph(object): 
    def __init__(self): 
     self.nodes = set() 
     # record positions of each node so that we can check for overlaps 
     self.positions = dict() 

    def add(self, node): 
     global count 
     count = 0 
     added = False 
     # add node at random location 
     while not added: 
      x, y = (randrange(0, SIZE[0], GRIDSPACING), 
         randrange(0, SIZE[1], GRIDSPACING)) 
      if not (x,y) in self.positions: 
       added = True 
       self.nodes.add(node) 
       node.setpos((x,y), self) 
      count += 1 
      if count >= MAXTRIES: 
       raise ValueError("Could not alocate space for node representation") 


    def update(self): 
     SCREEN.fill(BGCOLOR) 
     for node in self.nodes: 
      pygame.draw.rect(SCREEN, node.color, node.rect, 5) 
      textSurf = BASICFONT.render(str(node.id), True, TEXTCOLOR) 
      textRect = textSurf.get_rect() 
      textRect.center = int(node.rect[0] + 13),int(node.rect[1] + 13) 
      SCREEN.blit(textSurf, textRect) 
      for neighbor in node.neighbors: 
       pygame.draw.line(SCREEN, NODECOLOR,node.rect.center, neighbor.rect.center) 


class Node(object): 
    # incremented with each 
    # each node has a unique ID that 
    creation_counter = 0 
    def __init__(self): 
     self.id = self.__class__.creation_counter 
     self.__class__.creation_counter += 1 
     self.rect = None 
     self.color = NODECOLOR 
     self.neighbors = set() 

    def setpos(self, pos, graph = None): 
     if self.rect and graph: 
      # remove self from previous position in the graph: 
      graph.positions.pop(self.rect.topleft, None) 
     self.rect = pygame.Rect(pos[0], pos[1],NODESIZE[0], NODESIZE[1]) 
     if graph: 
      graph.positions[pos] = self 

    def __hash__(self): 
     return self.id 


def create_graph(): 
    # create new graph: 
    graph = Graph() 
    nodes = [] 
    for i in range(STARTINGNODES): 
     node = Node() 
     graph.add(node) 
    return graph 

def init(): 
    global SCREEN 
    pygame.init() 
    SCREEN = pygame.display.set_mode(SIZE) 

def quit(): 
    pygame.quit() 

def main(): 

    global BASICFONT, screen 

    graph = create_graph() 
    selected = None 
    try: 
     init() 
     BASICFONT = pygame.font.Font('freesansbold.ttf', BASICFONTSIZE) 
     while True: 
      graph.update() 
      pygame.event.pump() 
      # Exit "ESC" key is pressed 
      if pygame.key.get_pressed()[pygame.K_ESCAPE]: 
       break 
      for event in pygame.event.get(): 
       if event.type == pygame.MOUSEBUTTONDOWN: 
        x, y = event.pos 
        # round down x,y to multiples of NODESIZE 
        x -= x % NODESIZE[0] 
        y -= y % NODESIZE[1] 
        pygame.draw.rect(SCREEN, (0,0,255), (x,y) + NODESIZE) 
        if (x,y) in graph.positions: 
         node = graph.positions[x,y] 
         if selected: 
          print selected.id, node.id 
          if selected is node: 
           selected = None 
           node.color = NODECOLOR 
          elif selected not in node.neighbors: 
           selected.neighbors.add(node) 
           node.neighbors.add(selected) 
          else: 
           selected.neighbors.remove(node) 
           node.neighbors.remove(selected) 
         else: 
          node.color = (0,0,0) 
          selected = node 
        elif selected: 
         selected.setpos((x,y), graph) 
       elif event.type == pygame.MOUSEMOTION and event.buttons[0] and selected: 
        x, y = event.pos 
        # round down x,y to multiples of NODESIZE 
        x -= x % NODESIZE[0] 
        y -= y % NODESIZE[1] 
        selected.setpos((x,y), graph) 

      pygame.display.flip() 
      pygame.time.delay(FR) 
    finally: 
     quit() 


if __name__ == "__main__": 
    main()