I am referring to the flicker that occurs when you do not clear the background each frame:

http://code.google.com/p/processing/issues/detail?id=146

This is something that does not affect every system,... I have several systems that work just fine, but I would like to provide a fix for those that are having the problem.

- The main problem system is using an nvidia Quadro FX 4600 video card, so it's not a cheap integrated card.
- I've tried disabling Aero (running vista x64 here)
- drivers have all been updated
- tried disabling smoothing

I really need to run this in OPENGL, because the other modes are too slow, or do not support what I am drawing. (specifically textured quad strips)

Any suggestions?

edit: These are not my actual code, but something I have broken down to the bare minimum to hopefully show the problems I am having.

First, the extremely basic code. This will flicker on machines that exhibit the bug.

1. // trying to get rid of the flicker caused by using OPENGL
   // when you do not clear the screen each frame.
   
   // this simple example will flicker on some machines
   
   import processing.opengl.*;
   
   void setup(){
     size(500,500,OPENGL);
     background(255);
   }
   
   void draw(){
     line(mouseX,mouseY,pmouseX,pmouseY);
   }
   

second, this will fix (slowly) the issue by copying the buffer at the end of each draw cycle, and pasting it at the beginning. How can I speed this up?

1. // trying to get rid of the flicker caused by using OPENGL
   // when you do not clear the screen each frame.
   
   // this appears to fix the flicker, but is not very efficient
   PImage buffer;
   
   import processing.opengl.*;
   
   void setup(){
     size(500,500,OPENGL);
     background(255);
     buffer = get(); // grab frame for the first loop through
   }
   
   void draw(){
     image(buffer,0,0);  // start of draw cycle, draw last frame
     line(mouseX,mouseY,pmouseX,pmouseY);
     buffer = get(); // end of draw cycle, grab frame
   }
   

third,... now the "fix" does not work, because the drawing occurs in mouseDragged(). Any ideas how to get this to work?
edit: ok, this will work if I do the get() right after drawing the line inside mouseDragged(), but can anyone help speed this up at all?

1. // trying to get rid of the flicker caused by using OPENGL
   // when you do not clear the screen each frame.
   
   // by moving the drawing into mouseMoved(),copying the buffer does not work,... why?
   PImage buffer;
   
   import processing.opengl.*;
   
   void setup(){
     size(500,500,OPENGL);
     background(255);
     buffer = get();
   }
   
   void draw(){
     image(buffer,0,0);  // start of draw cycle, draw last frame
     buffer = get(); // end of draw cycle, grab frame
   }
   
   void mouseDragged(){
     line(mouseX,mouseY,pmouseX,pmouseY);
   }