[hatari-devel] New option --disable-video and --benchmark

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Hi

I just added 2 new options to Hatari's command line :

 --disable-video : don't refresh the screen during emulation. Emulated 
screen is still updated into Hatari's internal buffer, but the result is 
never displayed on screen through SDL calls.
This can be useful if you just want to listen to Hatari's sound without 
the extra cpu needed to display on screen (for example a music disk).
It can also be useful with the --benchmark option below to disable as 
many OS interaction as possible.
Note that main window is stil created (for keyboard input), but only 
refreshed when displaying the F12 menu.

 --benchmark : similar to fast forward mode, Hatari will run at maximum 
possible speed allowed by the host CPU. By disabling sound output and 
video output, one can remove most of SDL/OS calls and get a better 
measure of Hatari's inner work.

This can then be used to test different emulation options (cpu accuracy, 
video, sound, ...) and see the effect (speedup / slowdown) it implies on 
the global emulation.
For example, I plan to use this to test different shifter rendering 
methods and ensure there's no major slowdown.

For repeatable measures, best would be to save memstate at some point, 
then restore it without audio/video and run it for a large number of VBL 
for example :

hatari --memstate test.sav --sound off --disable-video 1 --run-vbls 10000

Nicolas