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我在我的java程序中有一个圆圈。它只是一个这样的简单圆：Java插入椭圆形图像
private BufferedImage img;
Graphics2D g = img.createGraphics();
g.fill(new Area(new Ellipse2D.Double(x, y, diam, diam)));
现在我想插入一个图像到圈子里。我知道我可以如何使用drawImage创建一个图像，如下所示：
image = Toolkit.getDefaultToolkit().getImage(url);
g2.drawImage(image, x, y, WIDTH, HEIGHT, null);
但是，如何在圈内创建图像？
编辑： 我试图做ControlAltDel建议的剪辑，但它不工作，我不知道为什么。我的代码是波纹管。 我的程序只用简单的黄色圆圈就可以正常工作。在文件Pang.java中，我试图替换下面的代码： g.fill（bubbles [i] .getBubbleArea（））;通过： Image image = new ImageIcon（“bubble.png”）。getImage（）; g .clip（新的Ellipse2D.Double（100，100，50，5））; g.drawImage（image，150，180，null）; 但它不工作，我donst得到任何错误。 我在做什么错？
Pang.java：
package pang.gui;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import java.awt.TexturePaint;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
class ShapeCollision {
\t private BufferedImage img;
\t private Area limits;
\t private int w = 800;// width of the game window
\t private int h = 400;// heigth of the game window
\t // private Bubble bubble = new Bubble(w, h);
\t private Bubble[] bubbles = new Bubble[4];
\t ShapeCollision() {
\t \t img = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
\t \t /**
\t \t * global image of the game shown in the window. This image will be
\t \t * added to the JLabel (imageLabel)
\t \t */
\t \t final JLabel imageLabel = new JLabel(new ImageIcon(img));
\t \t /**
\t \t * JLabel that contains the global image of the game
\t \t */
\t \t for (int i = 0; i < bubbles.length; i++) {
\t \t \t bubbles[i] = new Bubble(40 + i * 80, 40 + i * 80,i);
\t \t }
\t \t limits = new Area(new Rectangle(0, 0, w, h));
\t \t /**
\t \t * game limits or painted area
\t \t */
\t \t ActionListener animate = new ActionListener() {
\t \t \t @Override
\t \t \t public void actionPerformed(ActionEvent e) {
\t \t \t \t animate();
\t \t \t \t imageLabel.repaint();
\t \t \t }
\t \t };
\t \t Timer timer = new Timer(50, animate);
\t \t /**
\t \t * Repaint rate
\t \t */
\t \t timer.start();
\t \t JOptionPane.showMessageDialog(null, imageLabel);
\t \t timer.stop();
\t }
\t public void animate() {
\t \t Graphics2D g = img.createGraphics();
\t \t /**
\t \t * Creates a Graphics2D, which can be used to draw into this
\t \t * BufferedImage (img).
\t \t */
\t \t g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
\t \t \t \t RenderingHints.VALUE_ANTIALIAS_ON);
\t \t /**
\t \t * removes edges from the shape, makes rounder objects
\t \t */
\t \t g.setColor(Color.BLUE);
\t \t /**
\t \t * color of the game windows background
\t \t */
\t \t g.fillRect(0, 0, img.getWidth(), img.getHeight());
\t \t /**
\t \t * size of the Graphics2D object (g). In this case the game window is
\t \t * filled
\t \t */
\t \t for (Bubble bubble : bubbles) {
\t \t \t bubble.IncrementPos();
\t \t \t bubbleWallCollision(bubble);
\t \t }
\t \t for (Bubble bubble : bubbles) {
\t \t \t detectBubblesCollisions(bubble);
\t \t }
\t \t g.setColor(Color.YELLOW);
\t \t for (int i = 0; i < bubbles.length; i++) {
//Image image = new ImageIcon("bubble.png").getImage();
//g.clip(new Ellipse2D.Double(100, 100, 50,
// \t \t 5));
//g.drawImage(image, 150, 180, null);
\t \t \t g.fill(bubbles[i].getBubbleArea());
\t \t \t /**
\t \t \t * the bubble is filled *after* the obstacles, so the bubble is
\t \t \t * allways shown. If the bubble is on top of an abstacle that
\t \t \t * obstacle is covered by the bubble
\t \t \t */
\t \t }
\t \t g.dispose();
\t }
\t private void detectBubblesCollisions(Bubble bubble1) {
\t \t for (Bubble bubble : bubbles) {
\t \t \t if (bubble1 != bubble) {
\t \t \t \t if (bubble1.getX() + bubble1.getBubbleDiam()/2
\t \t \t \t \t \t + bubble.getBubbleDiam()/2 > bubble.getX()
\t \t \t \t \t \t && bubble1.getX() < bubble.getX()
\t \t \t \t \t \t \t \t + bubble1.getBubbleDiam()/2
\t \t \t \t \t \t \t \t + bubble.getBubbleDiam()/2
\t \t \t \t \t \t && bubble1.getY() + bubble1.getBubbleDiam()/2
\t \t \t \t \t \t \t \t + bubble.getBubbleDiam()/2 > bubble.getY()
\t \t \t \t \t \t && bubble1.getY() < bubble1.getY()
\t \t \t \t \t \t \t \t + bubble1.getBubbleDiam()/2
\t \t \t \t \t \t \t \t + bubble.getBubbleDiam()/2) {
\t \t \t \t \t if (PangUtilities.areasDistance(bubble1, bubble) < bubble1
\t \t \t \t \t \t \t .getBubbleDiam()/2 + bubble.getBubbleDiam()/2) {
\t \t \t \t \t \t calculateNewVelocities(bubble1, bubble);
\t \t \t \t \t }
\t \t \t \t }
\t \t \t }
\t \t }
\t }
\t private void calculateNewVelocities(Bubble bubble1, Bubble bubble) {
\t \t double mass1 = bubble1.getBubbleDiam()/2;
\t \t double mass2 = bubble.getBubbleDiam()/2;
\t \t double velX1 = bubble1.get_xDelta();
\t \t double velX2 = bubble.get_xDelta();
\t \t double velY1 = bubble1.get_yDelta();
\t \t double velY2 = bubble.get_yDelta();
\t \t double newVelX1 = (velX1 * (mass1 - mass2) + (2 * mass2 * velX2))/(mass1 + mass2);
\t \t double newVelX2 = (velX2 * (mass2 - mass1) + (2 * mass1 * velX1))/(mass1 + mass2);
\t \t double newVelY1 = (velY1 * (mass1 - mass2) + (2 * mass2 * velY2))/(mass1 + mass2);
\t \t double newVelY2 = (velY2 * (mass2 - mass1) + (2 * mass1 * velY1))/(mass1 + mass2);
\t
\t
\t bubble1.set_xDelta(newVelX1);
\t
\t bubble.set_xDelta(newVelX2);
bubble1.set_yDelta(newVelY1);
\t
\t bubble.set_yDelta(newVelY2);
bubble1.setX(bubble1.getX() + newVelX1);
bubble1.setY(bubble1.getY() + newVelY1);
\t
bubble.setX(bubble.getX() + newVelX2);
bubble.setY(bubble.getY() + newVelY2);
\t }
\t private void bubbleWallCollision(Bubble bubble) {
\t \t if (bubble.getX() + bubble.getBubbleDiam()/2 >= w
\t \t \t \t && bubble.get_xDelta() > 0)
\t \t \t bubble.invert_xDelta();
\t \t if (bubble.getX()-bubble.getBubbleDiam()/2 <= 0 && bubble.get_xDelta() < 0)
\t \t \t bubble.invert_xDelta();
\t \t if (bubble.getY() + bubble.getBubbleDiam()/2 >= h
\t \t \t \t && bubble.get_yDelta() > 0)
\t \t \t bubble.invert_yDelta();
\t \t if (bubble.getY()-bubble.getBubbleDiam()/2 <= 0 && bubble.get_yDelta() < 0)
\t \t \t bubble.invert_yDelta();
\t }
\t public static void main(String[] args) {
\t \t Runnable r = new Runnable() {
\t \t \t @Override
\t \t \t public void run() {
\t \t \t \t new ShapeCollision();
\t \t \t }
\t \t };
\t \t SwingUtilities.invokeLater(r);
\t }
}Bubble.java：
package pang.gui;
import java.awt.Shape;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
public class Bubble {
\t private Area bubbleArea = new Area();
\t private double bubbleDiam = 20, bubbleSpeed = 2;// bubble diameter
private Shape shape;
\t private double x;
\t private double y;
\t private int initialDirectionX, initialDirectionY;
\t private double xDelta = bubbleSpeed;// bubble move increments
\t private double yDelta = bubbleSpeed;// bubble move increments
\t public Bubble(int x, int y,int i) {
\t \t this.x = x;// Bubble position
\t \t this.y = y;// Bubble position
\t \t this.bubbleDiam *=i+1;
\t \t System.out.println(bubbleDiam);
\t \t genDirection();
\t }
\t public void IncrementPos() {
\t \t x += xDelta;// new position of the bubble
\t \t y += yDelta;// new position of the bubble
\t \t this.bubbleArea = new Area(new Ellipse2D.Double(x-bubbleDiam/2, y-bubbleDiam/2, bubbleDiam,
\t \t \t \t bubbleDiam));// bubble area definition
\t \t shape=new Ellipse2D.Double(x-bubbleDiam/2, y-bubbleDiam/2, bubbleDiam,
\t \t \t \t bubbleDiam);
\t }
\t
\t
\t public Shape getShape() {
\t \t return shape;
\t }
\t public void setX(double d) {
\t \t this.x = d;
\t }
\t public void setY(double d) {
\t \t this.y = d;
\t }
\t public Area getBubbleArea() {
\t \t return bubbleArea;
\t }
\t public double getBubbleDiam() {
\t \t return bubbleDiam;
\t }
\t public double get_xDelta() {
\t \t return xDelta;
\t }
\t public double get_yDelta() {
\t \t return yDelta;
\t }
\t public void set_xDelta(double d) {
\t \t this.xDelta = d;
\t }
\t public void set_yDelta(double d) {
\t \t this.yDelta = d;
\t }
\t public void invert_yDelta() {
\t \t yDelta *= -1;
\t }
\t public void invert_xDelta() {
\t \t xDelta *= -1;
\t }
\t public double getX() {
\t \t return x;
\t }
\t public double getY() {
\t \t return y;
\t }
\t private void genDirection() {
\t \t do {
\t \t \t initialDirectionX = PangUtilities.genRandomInt(-3, 3);
\t \t } while (initialDirectionX == 0);
\t \t do {
\t \t \t initialDirectionY = PangUtilities.genRandomInt(-3, 3);
\t \t } while (initialDirectionX == initialDirectionY
\t \t \t \t || initialDirectionY == 0);
\t \t xDelta *= initialDirectionX;
\t \t yDelta *= initialDirectionY;
\t }
}PangUtilities.java：
package pang.gui;
import java.util.Random;
public class PangUtilities {
\t public static int genRandomInt(int min, int max) {
\t \t Random rand = new Random();
\t \t return min + rand.nextInt((max - min) + 1);
\t }
\t public static double areasDistance(Bubble b1, Bubble b2) {
\t \t double distance = Math
\t \t \t \t .sqrt(((b1.getX() - b2.getX()) * (b1.getX() - b2.getX()))
\t \t \t \t \t \t + ((b1.getY() - b2.getY()) * (b1.getY() - b2.getY())));
\t \t return distance;
\t }
}
是否像这样剪贴？：Image image = new ImageIcon（“image.png”）。getImage（）; g.clip（new Ellipse2D.Double（x，y，d， \t \t d））; g.drawImage（image，x，y，null）; – user2880113
是的，你就是这么做的，虽然我建议你保持你的裁剪形状，而不是每次都做一个新形状 – ControlAltDel