Help with double buffer

I have a series of images that I display on a jLabel using imageIcon that get loaded depending on the mouse position on the label. I would like to preload these images somehow so that there is no wait time for the user when these images are called up. It seems that the doublebuffer object might help with this but I am not sure how....Any help appreciated..
Jacques

Well you can create an array of Image Icons and put you images there ...
ImageIcon[] myImages = new ImageIcon[number_Of_Images]; -MaxxDmg
- ' He who never sleeps...'

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import javax.swing.*;
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* @version 1.0 2002-07-04
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/Andrew

I've solved it!
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Reposted and answered at:
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Need to output 8 channels using double buffer

Hi,
I need to ouput 8 channels to the DAQ card.
I am getting an array 8 bytes of data every 10 milliseconds.
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Attachments:
WFMdoubleBuf.C ‏8 KB

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I need help with event structure.
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Help needed with doubles and integers

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Revision: 1991
Author: [email protected]
Date: 2008-06-06 19:05:02 -0700 (Fri, 06 Jun 2008)
Log Message:
Also reducing HexEncoder buffer size from 64K to 32K to help with the smaller stack size of the AVM on Mac as part of fix for SDK-15232.
QE: Yes, please test mx.utils.HexEncoder with ByteArrays larger than 64K on PC and Mac too.
Doc: No
Checkintests: Pass
Bugs:
SDK-15232
Ticket Links:
http://bugs.adobe.com/jira/browse/SDK-15232
http://bugs.adobe.com/jira/browse/SDK-15232
Modified Paths:
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Revision: 1990
Author: [email protected]
Date: 2008-06-06 18:53:36 -0700 (Fri, 06 Jun 2008)
Log Message:
Reducing Base64Encoder buffer size from 64K to 32K to help with the smaller stack size of the AVM on Mac.
QE: Yes, please test mx.utils.Base64Encoder with Strings and ByteArrays larger than 64K on PC and Mac after these changes.
Doc: No
Checkintests: Pass
Bugs:
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Ticket Links:
http://bugs.adobe.com/jira/browse/SDK-15232
Modified Paths:
flex/sdk/branches/3.0.x/frameworks/projects/framework/src/mx/utils/Base64Encoder.as

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Double Buffer program is slowing down, help.

Hello, I have a small Dancing Lines program like an old Windows screensaver program and it appears to slow down after about 30 seconds to a minute. I "clear" my buffer by copying a screen sized black symbol to the buffer. If anyone has any ideas about how to make this more efficient and most importantly stop the slow down, please let me know, thanks.
// Variables
var x0:int;
var y0:int;
var x1:int;
var y1:int;
var x2:int;
var y2:int;
var x3:int;
var y3:int;
var dx0:int;
var dy0:int;
var dx1:int;
var dy1:int;
var dx2:int;
var dy2:int;
var dx3:int;
var dy3:int;
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var drawing:Shape = new Shape();
var color1:uint = uint(0xFFFFFF * Math.random());
// Initialize Line Values
x0 = int(Math.random() * 320);
x1 = int(Math.random() * 320);
y0 = int(Math.random() * 200);
y1 = int(Math.random() * 200);
x2 = x0;
x3 = x1;
y2 = y0;
y3 = y1;
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dx0 = int(Math.random() * 5);
dx1 = int(Math.random() * 5);
dy0 = int(Math.random() * 5);
dy1 = int(Math.random() * 5);
dx2 = dx0;
dx3 = dx1;
dy2 = dy0;
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var buffer:BitmapData = new BitmapData(stage.stageWidth,stage.stageHeight,true,0xff000000);
var image:Bitmap = new Bitmap(bitmap);
addChild(image);
// Listeners
addEventListener(Event.ENTER_FRAME,onEnterFrame);
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     if ((y1 += dy1) >= 195 || y1 < 5)
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          drawing.graphics.lineTo(x3,y3);
          if ((x2 += dx2) >= 315 || x2 < 5)
               dx2 *= -1;
          if ((y2 += dy2) >= 195 || y2 < 5)
               dy2 *= -1;
          if ((x3 += dx3) >= 315 || x3 < 5)
               dx3 *= -1;
          if ((y3 += dy3) >= 195 || y3 < 5)
               dy3 *= -1;
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P.S. - Is there a way I can post my code in a smaller box with a scrollbar?

Here is a fixed version:
// Variables
var x0:int;
var y0:int;
var x1:int;
var y1:int;
var x2:int;
var y2:int;
var x3:int;
var y3:int;
var dx0:int;
var dy0:int;
var dx1:int;
var dy1:int;
var dx2:int;
var dy2:int;
var dx3:int;
var dy3:int;
var counter:int = 0;
var drawing:Shape = new Shape();
var color1:uint = uint(0xFFFFFF * Math.random());
// Initialize Line Values
x0 = int(Math.random() * 320);
x1 = int(Math.random() * 320);
y0 = int(Math.random() * 200);
y1 = int(Math.random() * 200);
x2 = x0;
x3 = x1;
y2 = y0;
y3 = y1;
// Initializing Line Velocities
dx0 = int(Math.random() * 5);
dx1 = int(Math.random() * 5);
dy0 = int(Math.random() * 5);
dy1 = int(Math.random() * 5);
dx2 = dx0;
dx3 = dx1;
dy2 = dy0;
dy3 = dy1;
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var bitmap:BitmapData = new BitmapData(stage.stageWidth,stage.stageHeight,true,0xff000000);
var buffer:BitmapData = new BitmapData(stage.stageWidth,stage.stageHeight,true,0xff000000);
var image:Bitmap = new Bitmap(bitmap);
addChild(image);
// Listeners
addEventListener(Event.ENTER_FRAME,onEnterFrame);
function onEnterFrame(event:Event):void {
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     drawing.graphics.lineStyle(1, color1);
     drawing.graphics.moveTo(x0,y0);
     drawing.graphics.lineTo(x1,y1);
     if ((x0 += dx0) >= 315 || x0 < 5)
          dx0 *= -1;
     if ((y0 += dy0) >= 195 || y0 < 5)
          dy0 *= -1;
     if ((x1 += dx1) >= 315 || x1 < 5)
          dx1 *= -1;
     if ((y1 += dy1) >= 195 || y1 < 5)
          dy1 *= -1;
     if (++counter > 50) {
          drawing.graphics.lineStyle(1, 0x000000);
          drawing.graphics.moveTo(x2,y2);
          drawing.graphics.lineTo(x3,y3);
          if ((x2 += dx2) >= 315 || x2 < 5)
               dx2 *= -1;
          if ((y2 += dy2) >= 195 || y2 < 5)
               dy2 *= -1;
          if ((x3 += dx3) >= 315 || x3 < 5)
               dx3 *= -1;
          if ((y3 += dy3) >= 195 || y3 < 5)
               dy3 *= -1;
     // Draw The Screen
     buffer.draw(drawing, drawing.transform.matrix);
     bitmap.draw(buffer);
     // clear drawing canvas
     drawing.graphics.clear();
Basically you have to use the graphics.clear() function to erase any clip where you are using the drawing API. Drawing lots of vectors can be very costly performance-wise so you always want to clear your graphics when you are finished. Drawing over the vectors with a rectangle has no effect except to increase the load even more. However when dealing with bitmap objects you can safely draw as much as you want for as long as you wish with no performance hit. Thats why what you were trying to do with that "clearBuffer" was not doing anything. Also, setting the counter to 51 when it got to 250 was doing nothing whatsoever. Not sure what that was for. The code should work fine now.

Help with double buffer

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