Home Page Forums MAME Non-Windows MAME Support SDL2 vs. SDL1 regressions

Right now the main one I'm aware of is that if you run a single-screen game with -numscreens 2 you get two windows each running at half the framerate. I am alarmed that this hasn't been reported, it makes me wonder if anyone is actually running 0.156. OG or Couriersud, if you're bored, please look at this as my house has a family infestation until Tuesday ;-)

Previously alt-enter behavior was strange, particularly on OS X. I fixed this several days ago in git and haven't heard anything bad since so I'm assuming it's better.

SDL2 on OS X double-detects gamepads sometimes. This is known and already fixed in SDL2's Mercurial; if/when the 2.0.4 release occurs this will be solved with no modifications to MAME/MESS.

How did you determine the frame rate per screen in this setup? And which options did you use?

Using

./mame64 -nomt -np 4 -str 60 galaxian -ad pulse -noautosave -video accel -numscreens 2 -sdlvideofps

I get

42.31s, 4993 F, avrg game: 118.02 FPS 8.47 ms/f, avrg video: 660.57 FPS 1.51 ms/f, last video: inf FPS 1.45 ms/f

with 118 =~ 2 * 60 - so nothing really wrong.

What am I missing?

Let me be more technically specific: the SDL2 OSD sees MAME's normal double-buffering and assigns the two double buffers to two different windows/screens.

mame64 -nomt pacman -video accel -numscreens 2 will open 2 windows. If you select one and press F11 to show the framerate you will see approximately 30 instead of the expected 60.1 or so. The framerate anomaly is, however, much less of an actual problem than the two double buffers being shown on two different windows/monitors though.

I've been running the latest and greatest with SDL2, but I don't have a machine with two monitors. Sorry for not being more useful.

You don't need two monitors to repo this. On one monitor with windowed mode and -numscreens 2 you'll just get two (perfectly overlapping) windows that behave as advertised.

I am a bit confused. Pressing F11 on screen 0 I just get "skip 0/10 100%". No FPS like 60 or 30.1. I used the following:

./mame64 -nomt -numscreens 2 pacman -ad pulse -video accel -inipath x -w -rp /mnt/mame/romlib/r -sdlvideofps

The "-inipath x" just disables all mame.ini processing. And the videofps output indicates 60 fps on both screens (121.18 ~= 2 x 60.6)

73.51s, 8907 F, avrg game: 121.18 FPS 8.25 ms/f, avrg video: 1206.96 FPS 0.83 ms/f, last video: inf FPS 0.94 ms/f

Please ignore the framerate: do you or do you not get two windows in that case? My objection is that pacman is a single screen game which we are opening two windows for; I don't immediately care about the framerate which is an obvious side effect of vsyncing the double buffers separately due to having them shown in indpendent windows. Also, please omit -sdlvideofps.

I do get two screens - one labelled "Screen 0" and the other "Screen 1". Both show the same game content. Mame UI elements (menus and speed/F11) only on Screen 0. If I use "-waitvsync" F11 delivers "skip 0/10 50%".

My understanding in the past was, that the mapping was the default behaviour:

numscreens=2, single screen game ==> game bitmap displayed on both screens.

I don't have a Windows build immediately on me, but as far as I'm aware Windows OSD does not behave that way; -numscreens 2 on a single-screen game still only opens one window/screen, and that's certainly the behavior I'd expect.

mame64.exe from mamedev.org will open two screens as well, i.e. behave exactly like OSD=sdl build. Just tested it.