java - Graphics2D 在定义的四边形内绘制图像

Question

我在 Graphics2D 中找不到绘图图像过载，这将使我能够执行这样的任务，有人可以帮我弄清楚如何做到这一点 - 最好不要切换到更高级的图形框架，如 OpenGL，

谢谢。

澄清一下，四边形可以由任何有四个边的东西来定义。这意味着钻石或矩形或更复杂的形状。

Mre 删除了他的许多言论，所以我似乎没有回应任何人，但我在评论中所说的只是对 mre 所说的话的回应。

Answer 1

See Andrew Thomson's solution for the basics.

Instead of using a "text shape", I created a Shape using:

Polygon polygon = new Polygon();
polygon.addPoint(250, 50);
polygon.addPoint(350, 50);
polygon.addPoint(450, 150);
polygon.addPoint(350, 150);
g.setClip(polygon);
g.drawImage(originalImage, 0, 0, null);

Answer 2

继承的Graphics图像绘制方法

1. drawImage(Image img, int x, int y, Color bgcolor, ImageObserver observer)
2. drawImage(Image img, int x, int y, ImageObserver observer)
3. drawImage(Image img, int x, int y, int width, int height, Color bgcolor, ImageObserver observer)
4. drawImage(Image img, int x, int y, int width, int height, ImageObserver observer)
5. drawImage(Image img, int dx1, int dy1, int dx2, int dy2, int sx1, int sy1, int sx2, int sy2, Color bgcolor, ImageObserver observer)
6. drawImage(Image img, int dx1, int dy1, int dx2, int dy2, int sx1, int sy1, int sx2, int sy2, ImageObserver observer)

选择你的毒药。由于您甚至无法找到这些，我假设在面对缩放和频繁渲染时详细介绍中间图像是徒劳的。

示例 1——在正方形中画一个圆

public class DrawCircleInSquare {

    public static void main(String[] args){
        SwingUtilities.invokeLater(new Runnable(){
            @Override
            public void run() {
                createAndShowGUI();
            }
        });
    }

    private static void createAndShowGUI(){
        final JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        final JPanel panel = new JPanel(){

            @Override
            protected void paintComponent(Graphics g){
                Graphics2D g2 = (Graphics2D)g.create();

                // Clear background to white
                g2.setColor(Color.WHITE);
                g2.clearRect(0, 0, getWidth(), getHeight());

                // Draw square
                g2.setColor(Color.BLACK);
                g2.drawRect(50, 50, 100, 100);

                // Draw circle inside square
                g2.setColor(Color.RED);
                g2.fillOval(88, 88, 24, 24);

                g2.dispose();
            }

            @Override
            public Dimension getPreferredSize(){
                return new Dimension(200, 200);
            }
        };

        frame.add(panel);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

输出

示例 2——在正方形中绘制图像

public class DrawImageInSquare {

    private static BufferedImage bi;

    public static void main(String[] args){
        try {
            // Load image
            loadImage();

            // Create and show GUI
            SwingUtilities.invokeLater(new Runnable(){
                @Override
                public void run() {
                    createAndShowGUI();
                }
            });
        } catch (IOException e) {
            // handle exception
        }
    }

    private static void loadImage() throws IOException{
        bi = ImageIO.read(new File("src/resources/psyduck.png"));
    }

    private static void createAndShowGUI(){
        final JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        final JPanel panel = new JPanel(){

            @Override
            protected void paintComponent(Graphics g){
                Graphics2D g2 = (Graphics2D)g.create();

                // Clear background to white
                g2.setColor(Color.WHITE);
                g2.clearRect(0, 0, getWidth(), getHeight());

                // Draw square
                g2.setColor(Color.BLACK);
                g2.drawRect(50, 50, 100, 100);

                // Draw image inside square
                g2.setRenderingHint(
                        RenderingHints.KEY_INTERPOLATION, 
                        RenderingHints.VALUE_INTERPOLATION_BICUBIC);
                g2.drawImage(bi, 50, 50, 100, 100, null);

                g2.dispose();
            }

            @Override
            public Dimension getPreferredSize(){
                return new Dimension(200, 200);
            }
        };

        frame.add(panel);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

输出