Just to add, it might help to just use g.setColor(...).fillRect(x,y,x+1,x+1) (without a different screen mode) for something like Mandelbrot - then it'll update the screen as and when the data is calculated.
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Just to add, it might help to just use
g.setColor(...).fillRect(x,y,x+1,x+1)
(without a different screen mode) for something like Mandelbrot - then it'll update the screen as and when the data is calculated.