Hello,
I am displaying a
BufferedImage in a JPanel and have some questions on
performance.
I use the
AffineTransform to scale and translate the BufferedImage in the
panel.
I also allow the
user to draw on top of the image by dragging the mouse (something like a paint
program). So as the user draws on top of the image, I need to keep calling
repaint() on the panel to update the image and the user's
drawing.
What I find is
this:
A. When my panel is
relatively small (for example an 8th of total screen area) and when the
image is not scaled up (fits entirely within the panel), I get good performance.
That is, the user's drawing keeps up with the motion of the mouse in the
panel.
B. When the panel is
relatively large (say half as large as the screen itself) and when the image is
scaled way up so that it does not fit within panel (say five times the size
of the panel itself), performance is very poor. By this I mean that the
user's drawing on top of the image lags significantly behind the movement
of the mouse.
All of my rendering
is done inside of the panel's paintComponent(...) method.
This is how I draw
the image:
g2d.drawImage(theImage.getBufferedImage(), 0, 0,
null);
Also, I am not
setting a clipping area.
At this point I'm
looking for some general advice on how to improve performance. I'm guessing that
this would involve setting a clipping region.
If so can some one
give some specific pointers on how to set the proper clipping region when
AffineTransform has been used to scale and pan the image so that the image is
much larger than the panel itself.
Thank
you,
Ted
Hill
===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff JAVA2D-INTEREST". For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".
