स्विंग

Question

में कैनवास पर छवि के विशिष्ट क्षेत्र को ज़ूम कैसे करें मैं छवि पर विशिष्ट क्षेत्र ज़ूम करना चाहता हूं। जिसे उपयोगकर्ता द्वारा चुना जाता है। स्विंग का उपयोग कर कैनवास पर छवि प्रदर्शन। मैंने पहले से ही कैनवास पर पूर्ण छवि ज़ूम किया है लेकिन विशिष्ट क्षेत्र ज़ूम लागू नहीं कर सकता है। कृपया

Answer 1

कैनवास awtswing नहीं है। इसके बजाय JPanel आज़माएं। Example।

लेकिन यदि आपने पहले से ही पूर्ण छवि ज़ूम किया है, तो उसे sub-image पर बनाने का प्रयास करें।

BufferedImage.getSubimage(x, y, w, h); 

संपादित

import java.awt.*; 
import java.awt.event.*; 
import java.awt.image.BufferedImage; 
import javax.swing.*; 

public class Example { 

    private Point startPoint = new Point(0, 0); 
    private Point rectLocale = new Point(); 
    private Dimension rectSize = new Dimension(); 
    private int zoom = 80; 
    private BufferedImage capture = null; 
    private BufferedImage raw; 

    public Example() throws Exception { 
     raw = new Robot().createScreenCapture(new Rectangle(
       Toolkit.getDefaultToolkit().getScreenSize())); 
     MouseBehavior behavior = new MouseBehavior(); 
     JPanel b = new JPanel() { 

      private static final long serialVersionUID = 1L; 

      @Override 
      public Dimension getMinimumSize() { 
       return new Dimension(500, 500); 
      } 

      @Override 
      public Dimension getPreferredSize() { 
       return new Dimension(500, 500); 
      } 

      @Override 
      protected void paintComponent(Graphics g) { 
       super.paintComponent(g); 
       Graphics2D g2d = ((Graphics2D) g); 
       g2d.drawImage(raw, 0, 0, null); 
       if (capture != null) { 
        int width2 = (int) (rectSize.width + rectSize.width * (zoom/500d)); 
        int height2 = (int) (rectSize.height + rectSize.height * (zoom/500d)); 
        int x2 = rectLocale.x - ((width2 - rectSize.width)/2); 
        int y2 = rectLocale.y - ((height2 - rectSize.height)/2); 
        Image scaledInstance = capture.getScaledInstance(
          width2, height2, Image.SCALE_AREA_AVERAGING); 
        g2d.drawImage(scaledInstance, x2, y2, null); 
        g2d.drawRect(x2, y2, width2, height2); 
       } else { 
        g2d.draw(new Rectangle(rectLocale, rectSize)); 
       } 
      } 
     }; 
     b.addMouseMotionListener(behavior); 
     b.addMouseListener(behavior); 
     b.addMouseWheelListener(behavior); 
     JFrame f = new JFrame(); 
     f.setLocation(10, 10); 
     f.setDefaultCloseOperation(3); 
     f.add(b); 
     f.pack(); 
     f.setVisible(true); 
    } 

    private class MouseBehavior extends MouseAdapter { 

     @Override 
     public void mousePressed(MouseEvent e) { 
      startPoint = e.getPoint(); 
      rectLocale = new Point(); 
      rectSize = new Dimension(); 
      capture = null; 
      if (e.getSource() instanceof JComponent) { 
       ((JComponent) e.getSource()).repaint(); 
      } 
     } 

     @Override 
     public void mouseDragged(MouseEvent e) { 
      Point currentPoint = e.getPoint(); 
      rectSize.width = Math.abs(currentPoint.x - startPoint.x); 
      rectSize.height = Math.abs(currentPoint.y - startPoint.y); 
      if (e.isShiftDown()) { 
       rectSize.width = rectSize.height = Math.min(
         rectSize.width, rectSize.height); 
       int dx = startPoint.x - rectSize.width; 
       int dy = startPoint.y - rectSize.height; 
       rectLocale.x = startPoint.x < currentPoint.x ? startPoint.x 
         : Math.max(dx, dy); 
       rectLocale.y = startPoint.y < currentPoint.y ? startPoint.y 
         : Math.min(dx, dy); 
      } else { 
       rectLocale.x = Math.min(currentPoint.x, startPoint.x); 
       rectLocale.y = Math.min(currentPoint.y, startPoint.y); 
      } 
      if (e.getSource() instanceof JComponent) { 
       ((JComponent) e.getSource()).repaint(); 
      } 
     } 

     @Override 
     public void mouseReleased(MouseEvent e) { 
      if (rectSize.width <= 0 || rectSize.height <= 0) { 
       capture = null; 
      } else { 
       capture = raw.getSubimage(Math.max(0, rectLocale.x), 
         Math.max(0, rectLocale.y), rectSize.width, rectSize.height); 
      } 
      if (e.getSource() instanceof JComponent) { 
       ((JComponent) e.getSource()).repaint(); 
      } 
     } 

     @Override 
     public void mouseWheelMoved(MouseWheelEvent e) { 
      zoom = Math.min(2000, Math.max(0, zoom + e.getUnitsToScroll() * 10)); 
      if (e.getSource() instanceof JComponent) { 
       ((JComponent) e.getSource()).repaint(); 
      } 
     } 
    } 

    public static void main(String[] args) { 
     EventQueue.invokeLater(new Runnable() { 

      @Override 
      public void run() { 
       try { 
        Example example = new Example(); 
       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 
    } 
}