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我有3天的時間尋找以螺旋方式在物體上移動，但我想我必須尋找在弧上移動物體的問題的一小部分。 看到我的問題：https://stackoverflow.com/questions/36917560/moving-rectangle-spiral-animation-java?noredirect=1#comment61428911_36917560沿着帶有java圖形的弧形路徑移動物體
現在，問題是我如何計算弧上存在的點。這是我的方法來獲得新的X和Y點（算法不代碼）
1-繪製弧形在Java中使用這種方法 g2d.fillArc（start_point_X_Arc，start_point_Y_Arc，width_of_arc，height_of_arc，start_angle，end_angle）;
2-在相同的Start_point_X，Start_point_Y上繪製對象。在這裏，我將使用這種方法繪製一個矩形
g2d.drawRect（start_point_X_Rect，Start_point_Y_Rect，10，10）;
3-因爲我使用一個計時器，它需要一個ActionListener actionPerformed方法將更新Start_point_X，Start_point_Y的值的矩形
與這裏的問題是我不能計算新X，Y值的值將會做問題的移動部分（我知道這些詞不是專業詞彙）。
正因爲如此我尋找如何計算電弧點，我發現對於圓形
X = center_X +半徑* COS（角度）
Y = center_y +半徑參數方程* sin（角度）
我知道這些公式可能會用來獲得新的積分，但我不擅長數學。
因此，我需要幫助做對象在弧形路徑中移動，我認爲這將幫助我做一個物體在螺旋路徑中移動。如果我的算法錯誤或任何錯誤，請給我建議，以簡單的方式做到這一點。
這是一個代碼，我讓它繪製一個圓弧&矩形，矩形在對角線路徑上移動。
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.AffineTransform;
import java.awt.geom.Arc2D;
import java.awt.geom.Path2D;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public class SpiralPath extends Path2D.Double {
public SpiralPath(int size) {
int numIterations = 5;
int arcGrowDelta = (size/numIterations)/2;
int arcWidth = 0;
int centerX = size/2;
int centerY = size/2;
moveTo(centerX, centerY);
for (int i = 0; i < numIterations; i++) {
append(new Arc2D.Double(centerX - arcWidth, centerY - arcWidth, 2 * arcWidth, 2 * arcWidth, 180, 180, Arc2D.OPEN), true);
arcWidth += arcGrowDelta;
append(new Arc2D.Double(centerX - arcWidth, centerY - arcWidth, 2 * arcWidth - arcGrowDelta, 2 * arcWidth, 0, 180, Arc2D.OPEN), true);
}
}
}
public class SpiralPath2 extends Path2D.Double {
public SpiralPath2(int size) {
int numIterations = 5;
int arcGrowDelta = (size/numIterations)/2;
int arcWidth = 0;
int centerX = size/2+200;
int centerY = size/2;
moveTo(centerX, centerY);
for (int i = 0; i < numIterations; i++) {
append(new Arc2D.Double(centerX - arcWidth, centerY - arcWidth, 2 * arcWidth, 2 * arcWidth, 180, 180, Arc2D.OPEN), true);
arcWidth += arcGrowDelta;
append(new Arc2D.Double(centerX - arcWidth, centerY - arcWidth, 2 * arcWidth - arcGrowDelta, 2 * arcWidth, 0, 180, Arc2D.OPEN), true);
}
}
}
public Test() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private SpiralPath spiralPath;
private final Rectangle box;
private List<Point2D> points;
private double angle;
private Point2D pos;
private int index;
private SpiralPath2 spiralPath2;
private final Rectangle box2;
private List<Point2D> points2;
private double angle2;
private Point2D pos2;
private int index2;
protected static final double PLAY_TIME = 5000; // 5 seconds...
private Long startTime;
public TestPane() {
spiralPath = new SpiralPath(150);
box = new Rectangle(0, 0, 10, 10);
points = new ArrayList<>(25);
PathIterator pi = spiralPath.getPathIterator(null, 0.01);
while (!pi.isDone()) {
double[] coords = new double[6];
switch (pi.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
case PathIterator.SEG_LINETO:
points.add(new Point2D.Double(coords[0], coords[1]));
break;
}
pi.next();
}
spiralPath2 = new SpiralPath2(200);
box2 = new Rectangle(0, 0, 10, 10);
points2 = new ArrayList<>(25);
PathIterator pi2 = spiralPath2.getPathIterator(null, 0.01);
while (!pi2.isDone()) {
double[] coords = new double[6];
switch (pi2.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
case PathIterator.SEG_LINETO:
points2.add(new Point2D.Double(coords[0], coords[1]));
break;
}
pi2.next();
}
pos = points.get(0);
pos2 = points2.get(0);
Timer timer = new Timer(40, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (startTime == null) {
startTime = System.currentTimeMillis();
}
long playTime = System.currentTimeMillis() - startTime;
double progress = playTime/PLAY_TIME;
if (progress >= 1.0) {
progress = 1d;
((Timer) e.getSource()).stop();
}
int index = Math.min(Math.max(0, (int) (points.size() * progress)), points.size() - 1);
int index2 = Math.min(Math.max(0, (int) (points2.size() * progress)), points2.size() - 1);
pos = points.get(index);
pos2 = points2.get(index2);
if (index < points.size() - 1) {
angle = angleTo(pos, points.get(index + 1));
}
if (index2 < points2.size() - 1) {
angle2 = angleTo(pos2, points2.get(index + 1));
}
repaint();
}
});
timer.start();
}
protected double angleTo(Point2D from, Point2D to) {
double angle = Math.atan2(to.getY() - from.getY(), to.getX() - from.getX());
return angle;
}
@Override
public Dimension getPreferredSize() {
return new Dimension(500, 400);
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
applyQualityRenderingHints(g2d);
g2d.translate(20, 50);
g2d.draw(spiralPath);
g2d.draw(spiralPath2);
AffineTransform at = new AffineTransform();
AffineTransform at2 = new AffineTransform();
if (pos != null &&pos2!=null) {
Rectangle bounds = box.getBounds();
at.rotate(angle, (bounds.width/2), (bounds.width/2));
Path2D player = new Path2D.Double(box, at);
g2d.translate(pos.getX() - (bounds.width/2), pos.getY() - (bounds.height/2));
g2d.setColor(Color.RED);
g2d.draw(player);
}
Rectangle bounds2 = box2.getBounds();
at2.rotate(angle2, (bounds2.width/2), (bounds2.width/2));
Path2D player2 = new Path2D.Double(box2, at2);
g2d.translate(pos2.getX() - (bounds2.width/2)+50, pos2.getY() - (bounds2.height/2));
g2d.setColor(Color.RED);
g2d.draw(player2);
g2d.dispose();
}
}
public static void applyQualityRenderingHints(Graphics2D g2d) {
g2d.setRenderingHint(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHint(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_ENABLE);
g2d.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g2d.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_PURE);
}
}
一種可能性是「作弊」一點（或者更重要的是，使用可用的API），如果可以生成螺旋的「路徑」，則可以使用「PathIterator」來查找所有點沿着那條路徑，然後你可以使用它作爲你的動畫/運動的基礎，[例如]（http://stackoverflow.com/questions/32392095/how-to-rotate-a-rectangle-after-reaching-specified -position/32397121＃32397121） – MadProgrammer
@MadProgrammer如果你檢查我對你的解決方案的評論，看看我的更新代碼 –