Graphics, AWT, Swing I part

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 Graphics, AWT, Swing

How can I minimise "Flicker" in animation? Solution 1:

Answer: Solution 1: 

Override update() : Flickering in animation occurs because default update() method

clears the screen of any existing contents and then calls paint(). To reduce flickering,

therefore, override update(). Here is how just add the following code to your applet: 

public void update(Graphics g) {

    paint(g);

}

What the update is now doing is just calling paint() and not clearing it, a further

refinement to the above will be to override update() method and painting only the

region where the changes are taking place. Here is how: 

public void update(Graphics g) {

    g.clipRect(x, y, w, h);

    paint(g);

}

Solution 2  will be described tomorrow

 How can I minimise "Flicker" in animation? Solution 2:

Solution 1 was described in our tip yesterday

Solution 2: 

Use double buffering : double buffering is the process of doing all your drawing to an

offscreen and then displaying the entire screen at once. It is called double buffering

because there are two drawing buffers and you switch between them. Use double

buffering only if the above solution alone does not work. The following code snippet

describes how to do it. 

Image offscreenImage;

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