Pygame实现Fitts定律时点击中点生成大量随机圆点的问题

问题根源 #

你当前用pygame.mouse.get_pressed()判断点击，这个方法在鼠标左键按住的每一帧都会返回True，而Pygame主循环每秒会运行几十到上百帧，所以按住鼠标时会连续执行生成圆点的代码，导致出现大量圆点。正确的做法是监听MOUSEBUTTONDOWN事件，这个事件只会在鼠标按下的瞬间触发一次。

修正后的代码 #

import pygame
import math  
import random

pygame.init()

width = 1024
height = 768
display = pygame.display.set_mode((width, height))

# 颜色定义
black = (0, 0, 0)
white = (255, 255, 255)
purple = (128, 0, 128)
grey = (128, 128, 128)
sky = (0, 0, 220)
blue = (85, 206, 255)
orange = (255, 127, 80)
red = (200, 0, 0)
light_red = (255, 0, 0)
green = (0, 200, 0)
light_green = (0, 255, 0)
colors = [white, grey, purple, sky, blue, orange, red, light_red, green, light_green]

clock = pygame.time.Clock() 

# 初始化目标圆点参数
current_pos = (512, 384)
current_color = green
current_radius = random.randint(14, 20)

while True:
    display.fill(black)  # 每一帧先清空屏幕
    # 绘制当前的目标圆点
    pygame.draw.circle(display, current_color, current_pos, current_radius)
    
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            quit()
        # 监听鼠标左键按下事件
        if event.type == pygame.MOUSEBUTTONDOWN and event.button == 1:
            x, y = event.pos
            # 计算鼠标与圆点中心的距离
            dx = x - current_pos[0]
            dy = y - current_pos[1]
            if math.sqrt(dx**2 + dy**2) < current_radius:
                # 根据当前圆点位置切换下一个目标
                if current_pos == (512, 384):
                    # 点击中间圆点，生成随机位置的彩色圆点
                    cx = random.randint(20, width - 20)
                    cy = random.randint(20, height - 20)
                    current_pos = (cx, cy)
                    current_color = random.choice(colors)
                    current_radius = random.randint(14, 20)
                else:
                    # 点击随机圆点，回到中间绿色圆点
                    current_pos = (512, 384)
                    current_color = green
                    current_radius = random.randint(14, 20)
    
    pygame.display.update()
    clock.tick(60)  # 限制帧率为60帧/秒

关键修改说明 #

• 改用MOUSEBUTTONDOWN事件处理点击，确保每次点击只触发一次生成逻辑
• 将屏幕清空和圆点绘制移到主循环开头，保证每一帧都正确渲染当前状态，避免残留之前的圆点
• 用current_pos、current_color、current_radius统一管理当前显示的圆点参数，逻辑更清晰
• 限制帧率为60，避免循环运行过快

内容的提问来源于stack exchange，提问作者Steve J