一个小动画向您展示了您需要在行旋转方面寻找的逻辑。可以把这条线想像成时钟上的指针。如何在时钟上设置一只手的动画。这几乎是完全相同的概念。唯一的不同是x1(指针的中心点的x点)而不是保持静止，而是在指针旋转时沿x轴线(y1恒定)移动。因此，对于时钟的每个刻度(指针旋转)，x位置也会水平移动。我就是这样看的。
在此处输入图片说明
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Main {
public static void main(String[] a) {
JFrame window = new JFrame();
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setResizable(false);
window.getContentPane().add(new MyCanvas());
window.pack();
window.setVisible(true);
}
}
class MyCanvas extends JPanel {
int x1 = 0;
int rotate = 50;
List lines;
Timer timer = null;
public MyCanvas() {
lines = new ArrayList<>();
timer = new Timer(75, new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (rotate < -50) {
((Timer) e.getSource()).stop();
} else {
lines.add(new Line(x1, rotate));
repaint();
x1 += 5;
rotate--;
}
}
});
JButton start = new JButton("Start the Magic");
start.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
timer.start();
}
});
add(start);
}
public Dimension getPreferredSize() {
return new Dimension(502, 400);
}
private static final long serialVersionUID = 1L;
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.BLACK);
g.fillRect(0, 0, getWidth(), getHeight());
for (Line line : lines) {
line.drawLine(g);
}
}
class Line {
int x1;
int rotate;
int y1 = 200;
public Line(int x1, int rotate) {
this.x1 = x1;
this.rotate = rotate;
}
void drawLine(Graphics g) {
int Radius = (int) (Math.min(getWidth(), getHeight()) * 0.4);
int sLength = (int) (Radius * 0.9);
int xSecond = (int) (x1 + sLength * Math.sin(rotate * (2 * Math.PI / 100)));
int ySecond = (int) (y1 - sLength * Math.cos(rotate * (2 * Math.PI / 100)));
g.setColor(Color.GREEN);
g.drawLine(x1, y1, xSecond, ySecond);
}
}
}
转播
