repaint updateArea

[hallo]

Hallo allerseits.

Bin schon seit einer weile an einem Problem dran, komme aber irgendwie nicht vorwärts.
Es geht darum, dass es ein Objekt gibt, welches einer Maus (MouseMotionListener) folgt.
Dies soll effizient geschehen, also nicht alles repainten. Nun da liegt das Problem.
Habe den Code mal auf das Essentielle getrimmt.


Die zeichnende Klasse:

import java.awt.Graphics;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;

import javax.swing.JFrame;
import javax.swing.JPanel;


public class Test {
	
	private JFrame frame;
	private JPanel panel;
	
	/** das zu zeichnende */
	private SomeDrawing drawing;
	
	private Point mouseLocation = new Point(0,0);
	
	public Test(){
		init();
	}
	
	private void init(){
		frame = new JFrame();
		panel = new JPanel(){
			@Override
			public void paintComponent(Graphics g){
				drawing.paintComponent(g);
			}
		};
		panel.addMouseMotionListener(new MouseMotionAdapter(){
			public void mouseMoved(MouseEvent arg0) {
				mouseLocation = arg0.getPoint();
			}
		});
		frame.getContentPane().add(panel);
		frame.setSize(50,500);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	}
	
	
	public void start(){
		drawing = new SomeDrawing(new Rectangle(10,50,5,50),this);
		// Thread der das gezeichnete updated
		Thread thread = new Thread(){
			public void run(){
				while(true){
					drawing.update(mouseLocation);
					try {
						Thread.sleep(25);
					} catch (InterruptedException e) {
						e.printStackTrace();
					}
				}
			}
		};
		thread.start();
	}
	
	public void repaint(Rectangle rect){
		//geht
//		panel.repaint(rect);
//		frame.repaint();
		
		//komisch
//		panel.repaint(rect);
//		frame.repaint(rect.x, rect.y, rect.width, rect.width);
		
		//möchte ich eigentlich o0der mindesten das obere
		panel.repaint(rect);
	}
	
	
	public static void main(String[] args){
		Test test = new Test();
		test.start();
	}

}

Das zu zeichnende Objekt:

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.Rectangle;


public class SomeDrawing {

	private Test test;
	private Rectangle bounds;

	public SomeDrawing(Rectangle bounds,  Test test) {
		this.test = test;
		this.bounds = bounds;
	}
	
	// zeichne das Quadrat
	public void draw(Graphics g) {
		g.setColor(Color.BLACK);
		g.drawRect(bounds.x, bounds.y, bounds.width, bounds.height);
	}

	// repainten des Area
	public void redraw(Rectangle r) {
		test.repaint(new Rectangle(r.x, r.y, r.height+1, r.width+1));
	}

	public void paintComponent(Graphics g) {
		draw(g);
	}
	
	public void update(Point mouseLocation){
		Point oldLocation = bounds.getLocation();
		Point newLocation = new Point(oldLocation.x, mouseLocation.y - (bounds.width)/2);

		if (!oldLocation.equals(newLocation)) {
			moveTo(newLocation);
		}
	}
	
	/**
	 * berechnet update area: alte Location UNION neu L
	 * 
	 */
	public void moveTo(Point p){
		Rectangle newLocation = new Rectangle(bounds);
		move(p);
		newLocation = newLocation.union(bounds);
		redraw(newLocation);
	}
	
	/**
	 * setzt neues Ort
	 */
	public void move(Point p){
		bounds.setLocation(p);
	}

}

Vielleicht sieht von euch jemand was ich da falsch mache.
Danke schon mals

 

[André Uhres]

Hallo hallo,
Ich hatte keine Lust, mich in dein Programm hineinzulesen.
Deshalb hier einfach nur ein Besipiel, wie es gehen könnte.
Gruß,
André

package demo; 
/* 
* SwingPaintDemo2.java 
*/ 

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

public class SwingPaintDemo2 { 

    private static void createAndShowGUI() { 
        JFrame f = new JFrame(); 
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        MyPanel panel = new MyPanel(); 
        Square square = new Square(new Rectangle(10, 50, 5, 50)); 
        panel.setSquare(square); 
        f.add(panel); 
        f.pack(); 
        f.setVisible(true); 
    } 

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

            public void run() { 
                createAndShowGUI(); 
            } 
        }); 
    } 
} 

class MyPanel extends JPanel { 

    private Square square; 

    public MyPanel() { 
        addMouseMotionListener(new MouseAdapter() { 

            @Override 
            public void mouseMoved(final MouseEvent e) { 
                square.moveSquare(e.getY()); 
            } 
        }); 
    } 

    public void setSquare(final Square square) { 
        square.setSquareContainer(this);
        this.square = square; 
    } 

    @Override 
    public Dimension getPreferredSize() { 
        return new Dimension(50, 500); 
    } 

    @Override 
    public void paintComponent(final Graphics g) { 
        super.paintComponent(g); 
        square.draw(g); 
    } 
} 

class Square { 

    private Rectangle bounds; 
    private JComponent squareContainer;

    public Square(final Rectangle bounds) { 
        this.bounds = bounds; 
    } 

    public void draw(final Graphics g) { 
        g.drawRect(bounds.x, bounds.y, bounds.width, bounds.height); 
    } 

    public void moveSquare(final int y) { 
        final int OFFSET = 1; 
        if (bounds.y != y) { 
            squareContainer.repaint(bounds.x, bounds.y, bounds.width + OFFSET, bounds.height + OFFSET); 
            bounds.y = y; 
            squareContainer.repaint(bounds.x, bounds.y, bounds.width + OFFSET, bounds.height + OFFSET); 
        } 
    }

    public void setSquareContainer(final JComponent squareContainer) {
        this.squareContainer = squareContainer;
    }
    
}

 

[Guest]

Danke André

hab mal rasgefunden an ws es liegt.

JComponent.repaint(Rectangele) --> nix gut
Component.repaint(x,y,w,h) --> bene

Doch stellt sich mir noch eine Frage.
Worin liegt der Unterschied dieser beiden Methoden?
Vielleicht weiss es grad jemand auf die schnelle?
Danke jedenfalls schonmal.

 

[André Uhres]

JComponent.repaint(Rectangele) --> nix gut
Component.repaint(x,y,w,h) --> bene
..Worin liegt der Unterschied dieser beiden Methoden?

Es gibt keinen wesentlichen Unterschied. Beide funktionieren gut bei mir :wink: