用java实现cyrus beck算法并把结果显示出来

以下是使用Java Swing和AWT库实现Cyrus-Beck算法的示例代码。该示例在窗口中绘制一个矩形和一个线段，并使用Cyrus-Beck算法将线段裁剪为一个新的线段。

import java.awt.*;
import javax.swing.*;

public class CyrusBeckAlgorithm extends JFrame {

    private static final long serialVersionUID = 1L;
    private JPanel panel;

    public CyrusBeckAlgorithm() {
        setTitle("Cyrus-Beck Algorithm");
        setSize(400, 400);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        panel = new JPanel() {
            private static final long serialVersionUID = 1L;
            Point P1 = new Point(100, 100);
            Point P2 = new Point(300, 300);
            Point winMin = new Point(150, 150);
            Point winMax = new Point(250, 250);

            public void paintComponent(Graphics g) {
                super.paintComponent(g);
                Graphics2D g2d = (Graphics2D) g;
                g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

                // 绘制裁剪窗口
                g2d.drawRect(winMin.x, winMin.y, winMax.x - winMin.x, winMax.y - winMin.y);

                // 绘制线段
                g2d.setStroke(new BasicStroke(2));
                g2d.drawLine(P1.x, P1.y, P2.x, P2.y);

                // 使用Cyrus-Beck算法裁剪线段
                cyrusBeckClip(P1, P2, winMin, winMax);

                // 绘制裁剪后的线段
                g2d.setColor(Color.RED);
                g2d.drawLine(P1.x, P1.y, P2.x, P2.y);
            }

            // Cyrus-Beck算法
            public void cyrusBeckClip(Point P1, Point P2, Point winMin, Point winMax) {
                double tE = 0.0, tL = 1.0;
                double dx = P2.x - P1.x;
                double dy = P2.y - P1.y;

                double[] normal = {0, 0, 0, 0};
                normal[0] = -dy; // left edge
                normal[1] = dx; // bottom edge
                normal[2] = dy; // right edge
                normal[3] = -dx; // top edge

                double[] PE = {P1.x - winMin.x, P1.y - winMin.y, winMax.x - P1.x, winMax.y - P1.y};

                for (int i = 0; i < 4; i++) {
                    double Pi = normal[i] * dx + normal[(i + 1) % 4] * dy;
                    double Qi = normal[i] * PE[i] + normal[(i + 1) % 4] * PE[(i + 1) % 4];
                    if (Pi == 0) {
                        if (Qi < 0) {
                            System.out.println("Line outside the clip window");
                            return;
                        }
                    } else {
                        double t = -Qi / Pi;
                        if (Pi < 0) {
                            tE = Math.max(tE, t);
                        } else {
                            tL = Math.min(tL, t);
                        }
                    }
                }

                if (tE > tL) {
                    System.out.println("Line outside the clip window");
                } else {
                    P1.x = (int) (P1.x + tE * dx);
                    P1.y = (int) (P1.y + tE * dy);
                    P2.x = (int) (P1.x + tL * dx);
                    P2.y = (int) (P1.y + tL * dy);
                    System.out.println("Line clipped from " + P1.toString() + " to " + P2.toString());
                }
            }
        };

        getContentPane().add(panel);
    }

    public static void main(String[] args) {
        CyrusBeckAlgorithm app = new CyrusBeckAlgorithm();
        app.setVisible(true);
    }
}

该示例将绘制一个矩形和一个线段，并使用Cyrus-Beck算法将线段裁剪为一个新的线段。运行程序后，您将看到窗口中绘制的图形，并在控制台中看到Cyrus-Beck算法输出的结果。