用pygame设计两个分子之间进行弹性碰撞，初始界面要能够定义分子的弹性系数的速度

好的，下面是一个简单的例子，使用Pygame设计了两个分子之间的弹性碰撞，并且可以在初始界面中定义分子的弹性系数和速度。

import pygame
import random
import math

# 初始化pygame
pygame.init()

# 设置窗口尺寸
size = width, height = 640, 480

# 创建窗口
screen = pygame.display.set_mode(size)

# 设置窗口标题
pygame.display.set_caption("弹性碰撞")

# 设置颜色
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)

# 定义分子类
class Molecule(pygame.sprite.Sprite):
    def __init__(self, x, y, radius, speed, angle, elasticity):
        super().__init__()
        self.x = x
        self.y = y
        self.radius = radius
        self.speed = speed
        self.angle = angle
        self.elasticity = elasticity
        self.image = pygame.Surface((radius*2, radius*2))
        self.image.fill(WHITE)
        pygame.draw.circle(self.image, BLACK, (radius, radius), radius)
        self.rect = self.image.get_rect()
        self.rect.center = (x, y)

    def update(self):
        # 移动分子
        self.x += self.speed * math.cos(self.angle)
        self.y -= self.speed * math.sin(self.angle)
        self.rect.center = (round(self.x), round(self.y))

        # 检查分子是否碰到边界
        if self.rect.left < 0 or self.rect.right > width:
            self.angle = math.pi - self.angle
            self.speed *= self.elasticity
        if self.rect.top < 0 or self.rect.bottom > height:
            self.angle = -self.angle
            self.speed *= self.elasticity

# 设置分子初始参数
m1 = Molecule(150, 150, 20, 5, math.pi/6, 0.9)
m2 = Molecule(450, 250, 30, 4, math.pi/4, 0.8)
all_sprites = pygame.sprite.Group(m1, m2)

# 设置时钟
clock = pygame.time.Clock()

# 设置弹性系数滑块
elasticity_slider = pygame.Surface((200, 20))
elasticity_slider.fill(WHITE)
pygame.draw.rect(elasticity_slider, BLACK, elasticity_slider.get_rect(), 2)
elasticity_slider_rect = elasticity_slider.get_rect(center=(320, 380))

# 设置速度滑块
speed_slider = pygame.Surface((200, 20))
speed_slider.fill(WHITE)
pygame.draw.rect(speed_slider, BLACK, speed_slider.get_rect(), 2)
speed_slider_rect = speed_slider.get_rect(center=(320, 430))

# 设置字体
font = pygame.font.Font(None, 30)

# 事件循环
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == pygame.MOUSEBUTTONDOWN:
            # 点击弹性系数滑块
            if elasticity_slider_rect.collidepoint(event.pos):
                elasticity_slider.fill(BLACK)
                elasticity_slider_rect.move_ip(event.rel)
                elasticity = elasticity_slider_rect.centerx / 640
                pygame.draw.rect(elasticity_slider, WHITE, elasticity_slider.get_rect().inflate(-4, -4))
                pygame.draw.rect(elasticity_slider, BLACK, elasticity_slider.get_rect(), 2)
            # 点击速度滑块
            elif speed_slider_rect.collidepoint(event.pos):
                speed_slider.fill(BLACK)
                speed_slider_rect.move_ip(event.rel)
                speed = speed_slider_rect.centerx / 640 * 10
                pygame.draw.rect(speed_slider, WHITE, speed_slider.get_rect().inflate(-4, -4))
                pygame.draw.rect(speed_slider, BLACK, speed_slider.get_rect(), 2)

    # 更新分子状态
    all_sprites.update()

    # 检查分子是否碰撞
    if pygame.sprite.collide_circle(m1, m2):
        dx = m1.x - m2.x
        dy = m1.y - m2.y
        distance = math.sqrt(dx**2 + dy**2)
        angle = math.atan2(dy, dx)
        m1.angle = 2 * angle - m1.angle
        m2.angle = 2 * angle - m2.angle
        m1.speed, m2.speed = m2.speed, m1.speed
        m1.speed *= m1.elasticity
        m2.speed *= m2.elasticity
        overlap = 0.5 * (m1.radius + m2.radius - distance + 1)
        m1.x += overlap * math.cos(angle)
        m1.y -= overlap * math.sin(angle)
        m2.x -= overlap * math.cos(angle)
        m2.y += overlap * math.sin(angle)
        m1.rect.center = (round(m1.x), round(m1.y))
        m2.rect.center = (round(m2.x), round(m2.y))

    # 绘制屏幕
    screen.fill(WHITE)
    all_sprites.draw(screen)
    screen.blit(elasticity_slider, elasticity_slider_rect)
    screen.blit(speed_slider, speed_slider_rect)
    elasticity_label = font.render("弹性系数: {:.1f}".format(elasticity), True, BLACK)
    screen.blit(elasticity_label, (20, 380))
    speed_label = font.render("速度: {:.1f}".format(speed), True, BLACK)
    screen.blit(speed_label, (20, 430))

    pygame.display.flip()

    # 设置帧率
    clock.tick(60)

在这个例子中，我们定义了一个Molecule类，用于表示分子。在初始化时，我们传入分子的位置、半径、速度、角度和弹性系数。在update()方法中，我们使用速度和角度计算分子的新位置，并且检查分子是否碰到边界。如果分子碰到边界，我们会根据碰撞的位置和角度更新分子的速度和角度。

我们还使用Pygame的sprite模块创建了一个all_sprites组，用于管理所有的分子。

在事件循环中，我们检查用户是否点击了弹性系数滑块或速度滑块，并且更新分子的弹性系数和速度。

最后，我们绘制屏幕并更新帧率。