microstutter in groovy mame 0.149

[stiegi]

Hello folks!

I have got a special question about gameplay in groovymame. It is not really a big concern but I am curious if someone encountered the same observation. The graphics in groovy mame are really smooth however I encountered the following issues. The graphics really run smoothly for some time but after a certain amount of time (I think this varies or can happen at a different point of time) there is a little "hickup" some sort of microstutter where the graphics motion is not smooth for a little time. I saw this in Bomb Jack when you move the character at the bottom from left to right it will run smoothly for some time but after a certain amount of time there is this little hickup in the movement. Another example is galaga where the star screen scrolls perfectly smooth but at about 20000 points there is this little hickup again. I also found this in other games as well. After this microstutter the game scrolls smoothly again until some time has passed and another short microstutter will occur.

Does anyone know what setting is responsible for this kind of behaviour - I guess as an "ideal" case the game should scroll/move perfectly all the time?

regards,
Alex

[Calamity]

http://forum.arcadecontrols.com/index.php/topic,113382.msg1546112.html#msg1546112

[adder]

I saw this in Bomb Jack when you move the character at the bottom from left to right it will run smoothly for some time but after a certain amount of time there is this little hickup in the movement

hi, to expand on Calamity's response, i think the bombjack hiccup is something which would occur on the real arcade pcb

to make the hiccup go away, you can use overclocking within mame to make the bombjack cpu cope better when eg. there is lots of action occurring on the screen (if i remember, the bombjack hiccup only occurs once there are quite a number of sprites on the screen at once, but do correct me if im wrong)

[stiegi]

hmmm I guess it depends on the game itself. for example in Twin Hawk this problem does not occur at all i.e. absolute smooth scrolling during the whole game.

[stiegi]

Thx Adder! I guess you are right that this also happens on the real pcb but I cannot tell since I havenīt seen a dedicated bomb jack cab with my own eyes. As a matter of fact there must be some "specific" driver or something else in a certain game which makes it more or less accurate as far as smooth movement is concerned. In other words a specific rom is more or less "compatible" to the the whole groovy mame system one has set up. I can tell from videos on you tube that pacman - especially the character sprite moves really smoothly but on my system the whole sprites move in the right speed but it is not really smooth - it seems that the sprites are "trembling" a little when they move - especially the character sprite which is definitely obvious to my eyes.

[Calamity]

Hi stiegi,

When I ask you to post logs it's not that I want to oppress you, it's because otherwise I can't provide concrete answers. You bring this subject back every few months, but without a log I can't see how your system is configured.

It is completely normal to see stutter on pacman's sprites if you run it rotated on a horizontal monitor, for instance (is this the case?) On the other hand, pacman runs perfectly smooth on its native orientation (and thus, native refresh).

Other games just don't update their background/sprites evenly, by design.