如何模拟轨道

import pygame
import math

# 初始化Pygame
pygame.init()

# 设置屏幕尺寸
screen_width, screen_height = 800, 600
screen = pygame.display.set_mode((screen_width, screen_height))

# 定义颜色
black = (0, 0, 0)
white = (255, 255, 255)

# 定义轨道参数
center_x, center_y = screen_width // 2, screen_height // 2
radius = 200

# 定义物体位置和速度
object_x, object_y = center_x, center_y - radius
velocity_x, velocity_y = 0, 2

# 游戏循环
running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    # 更新物体位置
    object_x += velocity_x
    object_y += velocity_y

    # 应用重力（简化模型）
    velocity_y += 0.1

    # 边界检测
    if object_y > screen_height:
        object_y = screen_height
        velocity_y *= -0.9  # 反弹并损失能量

    # 清屏
    screen.fill(black)

    # 绘制轨道
    pygame.draw.circle(screen, white, (center_x, center_y), radius, 2)

    # 绘制物体
    pygame.draw.circle(screen, white, (int(object_x), int(object_y)), 10)

    # 更新屏幕
    pygame.display.flip()

# 退出Pygame
pygame.quit()