Java 使用Graphics2D在BufferedImage上覆盖文本并返回BufferedImage

Java 使用Graphics2D在BufferedImage上覆盖文本并返回BufferedImage

该方法

drawString()

使用x和y作为最左边字符的基线。数字通常没有后代；如果true相同，则

text

在位置（0,0）绘制的字符串将完全在图像外部呈现。请参阅此示例。

附录：你可能会遇到图像中的颜色模型不兼容的问题。一种简单的方法是渲染图像，然后在原位对其进行修改。

import java.awt.Color;import java.awt.Dimension;import java.awt.EventQueue;import java.awt.Font;import java.awt.FontMetrics;import java.awt.Graphics;import java.awt.Graphics2D;import java.awt.image.BufferedImage;import java.io.IOException;import java.net.URL;import javax.imageio.ImageIO;import javax.swing.Jframe;import javax.swing.JPanel;public class TextOverlay extends JPanel {    private BufferedImage image;    public TextOverlay() {        try { image = ImageIO.read(new URL(     "http://cdn.sstatic.net/stackexchange/img/logos/so/so-logo.png"));        } catch (IOException e) { e.printStackTrace();        }        image = process(image);    }    @Override    public Dimension getPreferredSize() {        return new Dimension(image.getWidth(), image.getHeight());    }    private BufferedImage process(BufferedImage old) {        int w = old.getWidth() / 3;        int h = old.getHeight() / 3;        BufferedImage img = new BufferedImage( w, h, BufferedImage.TYPE_INT_ARGB);        Graphics2D g2d = img.createGraphics();        g2d.drawImage(old, 0, 0, w, h, this);        g2d.setPaint(Color.red);        g2d.setFont(new Font("Serif", Font.BOLD, 20));        String s = "Hello, world!";        FontMetrics fm = g2d.getFontMetrics();        int x = img.getWidth() - fm.stringWidth(s) - 5;        int y = fm.getHeight();        g2d.drawString(s, x, y);        g2d.dispose();        return img;    }    @Override    protected void paintComponent(Graphics g) {        super.paintComponent(g);        g.drawImage(image, 0, 0, null);    }    private static void create() {        Jframe f = new Jframe();        f.setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE);        f.add(new TextOverlay());        f.pack();        f.setVisible(true);    }    public static void main(String[] args) {        EventQueue.invokeLater(new Runnable() { @Override public void run() {     create(); }        });    }}