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330 Java Tips.pdf - FTP Server

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Graphics, AWT, Swing I part<br />

Receive our newsletter with new tips! Almost 6,000 subscribers (by June 2001) can not be wrong!<br />

They read our tips every week! To subscribe to The <strong>Java</strong> FAQ Daily send empty e-mail to:<br />

javafaq-tips-subscribe@topica.com or visit at:<br />

http://www.topica.com/lists/javafaq-tips/<br />

Graphics, AWT, Swing<br />

How can I minimise "Flicker" in animation? Solution 1:<br />

Answer: Solution 1:<br />

Visit us here and you will find<br />

much more tips!<br />

Override update() : Flickering in animation occurs because default update() method<br />

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

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

public void update(Graphics g) {<br />

paint(g);<br />

}<br />

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

refinement to the above will be to override update() method and painting only the<br />

region where the changes are taking place. Here is how:<br />

public void update(Graphics g) {<br />

g.clipRect(x, y, w, h);<br />

paint(g);<br />

}<br />

Solution 2 will be described tomorrow<br />

How can I minimise "Flicker" in animation? Solution 2:<br />

Solution 1 was described in our tip yesterday<br />

Solution 2:<br />

Use double-buffering : double buffering is the process of doing all your drawing to an<br />

file:///F|/350_t/350_tips/graphics-I.htm (1 of 6) [2002-02-27 21:18:07]

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