nanogui: GrArea slows down machine
Subject:
Re: [nanogui] GrArea slows down machine
From:
Alan Cox ####@####.####
Date:
11 Apr 2007 14:11:44 +0100
Message-Id: <20070411141428.6e93197c@the-village.bc.nu>
> So here is what my application does, and I really wonder whether it is
> possible to get the same effect with less CPU-cycles:
Have you profiled it on the embedded system to see what the performance
cost is and where it is slow - eg do you have floating point and is the
FP slow.
If I was doing this on an embedded box my instinct (and it is only that
as you've no profile info) would be to compute a table of line start/ends
and then for each movement
calculate a rectangle covering both old and new position
copy from the main memory version of the background picture into
the rectangle
draw the new line on it (main memory)
blit the rectangle to screen
but really you need profiling information to understand what is slowing
it down.
Alan
