Hacking [RELEASE] UAE4ALL - Amiga emulator

  • Thread starter Thread starter cpasjuste
  • Start date Start date
  • Views Views 83,525
  • Replies Replies 345
  • Likes Likes 12
Great emulator - it's almost perfect! Been having a lot of fun with it.

50fps games (Turrican 2 and Apidya are good examples) suffer from jitter. I think it's a performance problem as the jitter goes away and the game updates perfectly smoothly if I disable audio.

Also, some games are offset horizontally - if we were able to adjust the horizontal position of the display that would be cool.

The reason for jitter:
the Vita screen updates at 60 fps and the games at 50 fps, so there's jitter because of that, no way around it.

When you turn off sound the emulator switches to 60 fps, that is why you see jitter go away. Somehow UAE uses sound to sync to certain rates. It happened in old versions of WinUAE, too. So yes, you can get rid of jitter that way by switching off sound, but the games will run too fast then. But you could also switch the refresh rate to 60 Hz. Then it is smooth even with sound on. But again, your games will run too fast.

Note: to check your real fps, turn on "Status Line" and look at number in red square. You will see once you switch off sound, it changes from 50 to 60.

Horizontal offset:
Do you mean you are missing parts of the screen? You could try to use screen modes with larger width. E.g. select Preset Width 352 or 384 (lores) or 704 or 768 (hires). If you really just mean the screen is not centered horizontally, well, a horizontal shift could be implemented but would require a bit of work. Note even on a real Amiga, many games and WB Screenmodes were not centered perfectly horizontally. It was a limitation of the hardware.
 
  • Like
Reactions: Count Duckula
The reason for jitter:
the Vita screen updates at 60 fps and the games at 50 fps, so there's jitter because of that, no way around it.

When you turn off sound the emulator switches to 60 fps, that is why you see jitter go away. Somehow UAE uses sound to sync to certain rates. It happened in old versions of WinUAE, too. So yes, you can get rid of jitter that way by switching off sound, but the games will run too fast then. But you could also switch the refresh rate to 60 Hz. Then it is smooth even with sound on. But again, your games will run too fast.

Note: to check your real fps, turn on "Status Line" and look at number in red square. You will see once you switch off sound, it changes from 50 to 60.

Horizontal offset:
Do you mean you are missing parts of the screen? You could try to use screen modes with larger width. E.g. select Preset Width 352 or 384 (lores) or 704 or 768 (hires). If you really just mean the screen is not centered horizontally, well, a horizontal shift could be implemented but would require a bit of work. Note even on a real Amiga, many games and WB Screenmodes were not centered perfectly horizontally. It was a limitation of the hardware.

Hmm - I still get the jitter even when I set the refresh to 60. I can see the fps change in the status line, but the jitter only goes away if I disable sound.
 
Hmm - I still get the jitter even when I set the refresh to 60. I can see the fps change in the status line, but the jitter only goes away if I disable sound.

I think there are probably two sources of jitter: a) jitter coming from emu refresh not being equal to screen refresh of 60 Hz b) jitter coming from sound being on and forced to never drop samples. There was a lot of work Toni Wilen did on WinUAE back in the day to make sure sound does not crackle or change pitch while at the same time keep scrolling smooth. It was not trivial. I think in this emulator, sound has priority and can cause some frames to be delayed or drawn twice... but it is just a theory.

EDIT: Actually it might just be a) always. I think as long as sound is on there's always a slight (or large) mismatch between emu refresh and screen refresh, because the emulator is synching through the sound routines and will run at the exact Amiga frequency say even in 60 Hz mode that might be 59.97 Hz, while Vita screen might be at 60.01 Hz causing the observed jitter.
 
Last edited by rsn8887,
I think there are probably two sources of jitter: a) jitter coming from emu refresh not being equal to screen refresh of 60 Hz b) jitter coming from sound being on and forced to never drop samples. There was a lot of work Toni Wilen did on WinUAE back in the day to make sure sound does not crackle or change pitch while at the same time keep scrolling smooth. It was not trivial. I think in this emulator, sound has priority and can cause some frames to be delayed or drawn twice... but it is just a theory.

EDIT: Actually it might just be a) always. I think as long as sound is on there's always a slight (or large) mismatch between emu refresh and screen refresh, because the emulator is synching through the sound routines and will run at the exact Amiga frequency say even in 60 Hz mode that might be 59.97 Hz, while Vita screen might be at 60.01 Hz causing the observed jitter.
You're right - it's a two-fold problem. I did a few tests and played through the opening area of Turrican 2 a few times with different settings. I found that 50hz always jitters, but 60hz only jitters at high audio quality settings. If I drop audio down a notch or two to 22k or 32k then the jitter goes away but if I put it back up to 44k the jitter comes back.
 
  • Like
Reactions: lincruste
You're right - it's a two-fold problem. I did a few tests and played through the opening area of Turrican 2 a few times with different settings. I found that 50hz always jitters, but 60hz only jitters at high audio quality settings. If I drop audio down a notch or two to 22k or 32k then the jitter goes away but if I put it back up to 44k the jitter comes back.

Interesting! Thanks for testing and finding that out.
 
  • Like
Reactions: Dlk
has anyone been able to get a version of speedball 2 to work? if so which one/what settings?

cheers

EDIT - If anyone is interested the Speedball 2 - Brutal Deluxe.adf US version works - the first one I tried (Speedball2.adf) didn't. Awwsome game!
 
Last edited by RitchieRitchie,
  • Like
Reactions: lincruste
has anyone been able to get a version of speedball 2 to work? if so which one/what settings?

cheers

EDIT - If anyone is interested the Speedball 2 - Brutal Deluxe.adf US version works - the first one I tried (Speedball2.adf) didn't. Awwsome game!
Thanks, it works, indeed.
If anyone manages to get Jim Power to work, I'd like tovknow how, please. Someone here talked about an WHDL installation file but this is far beyond my emulation-fu.
 
  • Like
Reactions: RitchieRitchie
Looking for some help. First off, awesome emu, played lots of great games so thanks alot! I'm trying to run Swos1617 (sensible world of soccer). I've never used the HD to play games, only .adf files but swos comes in an HD folder (I think). I've gone to the 'Memory and Dicsk Options' but don't have a clue of what i'm supposed to do (I put the folder in 'HD Dir' but all I get is a white screen. Any suggestions?
 
Try changing blitter mode and resetting.
Looking for some help. First off, awesome emu, played lots of great games so thanks alot! I'm trying to run Swos1617 (sensible world of soccer). I've never used the HD to play games, only .adf files but swos comes in an HD folder (I think). I've gone to the 'Memory and Dicsk Options' but don't have a clue of what i'm supposed to do (I put the folder in 'HD Dir' but all I get is a white screen. Any suggestions?

First of all I would use the A1200 preset for HD files.

Then, you need to have either a single .hdf file, or a folder that contains the files of your game. Either way these need to contain all the files necessary to be bootable in addition to just the game files.

If you have a folder with many files, use the "HD_DIR" option in the emulator. Highlight the folder in the file selector and press the select button to select the folder (do not go into it, see instructions at the top of the menu display). Then also select "HD-Dir" as your boot device in the menu and your game should boot.

If you have a single .hdf file, select it as hdf file0 in the emu and select hdf file0 as your boot device. Again your game should then boot.

If it doesn't boot, chances are you do not have all the files necessary for a self-booting HD. You probably have a valid HD collection of files, but it is not self-booting. For example in a HD-Dir you need to have the file "startup-sequence" in the subfolder "s" to be able to boot. The same goes for the contents of your hdf file.

If that is the case, you need a full workbench installation (in a .hdf file) to actually start your game. Instead of going through the hassle of preparing a full workbench install, I would rather find a bootable .hdf file for your game, or have someone prepare one for you.
 
  • Like
Reactions: RitchieRitchie
Brilliant! Thanks for taking the time to answer, really appreciate it! Will give it a try when I get time later on today.

EDIT: Hmm, still not working (white screen) and the swos1617 dir has the start-up sequence file. If anyone ever gets it to work please share how you did it!
 
Last edited by RitchieRitchie,
Brilliant! Thanks for taking the time to answer, really appreciate it! Will give it a try when I get time later on today.

EDIT: Hmm, still not working (white screen) and the swos1617 dir has the start-up sequence file. If anyone ever gets it to work please share how you did it!

Hmm if you have a white screen, you are not booting an Amiga 1200. It works fine for me:

- Select A1200 config in menu
- Go to Hardisk options
- Select HD Dir
- Move ONTO the SW1617 Dir, and press SELECT to select the HD Dir, do NOT go INTO the dir, do NOT press x
- Under "Boot HD" select Dir
- Make sure no floppies are inserted
- Game boots fine

--------------------- MERGED ---------------------------

Thanks, it works, indeed.
If anyone manages to get Jim Power to work, I'd like tovknow how, please. Someone here talked about an WHDL installation file but this is far beyond my emulation-fu.

I just tried the gamebase Amiga floppy version called: Jim Power in Mutant Planet_Disk1.zip and Jim Power in Mutant Planet_Disk2.zip. No hdf needed.

- Unzip to get .adf files
- start uae4all2
- select the Disk 1 adf into DF0
- select Preset System Setup A500
- Press R to boot

Works just fine. However it is unplayable due to being so slow 26 fps.
 
Hmm if you have a white screen, you are not booting an Amiga 1200. It works fine for me:

- Select A1200 config in menu
- Go to Hardisk options
- Select HD Dir
- Move ONTO the SW1617 Dir, and press SELECT to select the HD Dir, do NOT go INTO the dir, do NOT press x
- Under "Boot HD" select Dir
- Make sure no floppies are inserted
- Game boots fine

--------------------- MERGED ---------------------------

Hi again, and thanks for taking the time to try it out. This is driving me nuts though as I'm still getting the white screen and I'm desperate to play the game! I'll tell you exactly what i do and I hope you can spot what I'm doing wrong.
1. Boot UAEALL
2. In the 'Preset System Setup' both 'A500' and 'A1200' are flashing. I move the cursor so it is only 'A1200' falshing.
3.Go to harddisk. I don't change any of the other options (Chip memory 2M, Slow mem off, Fast mem 8m) and selct HD Dir. I press selsct on the Swos1617 dir.
4. In Memory and disc Options I can see swos 1617 to the right of the flashing HD Dir. I move up to Boot HD and move it so that 'Dir' is flashing.
5. I press start and return to the main page. In DFO it says 'insert disk image'. I press start and am greeted with a white screen.

Any ideas?

A random thought, in the Misc page the kickstart is at 3.1. I copied a lot of kickstart roms to the kicks folder (I had them on pspuae) and there must be more than 50 - including about 20 versions of 3.1 I seem to remember in pspuae you could select the individual kickstart (maybe I'm wrong?) while in this you only have the 4 options.

If I start it up and change the kick to 2.0 or 3.1 and start the emu I am still greeted with the 'V1.3' underneath the 'Aimga Work bench' picture. Should this be 2.0 or 3.1?

Out of interest what Kickstart roms do you have in your kicks folder?

EDIT: I've removed all my kicks and just have 4. I somehow got it to work once but can't get it to work again. When I select 1200 do I then press R trigger?

EDIT: Sussed it out! Would never have done this without your help, cyber pint on me!

EDIT: I'm looking for HDF versions of the Settlers and Dune 2 - can anyone help? cheers!
 
Last edited by RitchieRitchie,
I haven't gotten sound effects to work in IK+ yet either.

I'd say there's no hope for a cycle exact setting unless someone wants to dig deeper into the emulator code and figure out how to add cycle exact to it.

Strangely enough, IK+ sound effects work on UAE4Arm on Android and that doesn't have a cycle exact option either. So it must be something else. It is probably some Blitter mode/CPU speed combination.
 
Last edited by rsn8887,
Strangely enough, IK+ sound effects work on UAE4Arm on Android and that doesn't have a cycle exact option either. So it must be something else. It is probably some Blitter mode/CPU speed combination.
Yes, and they don't work on UAE4ALL2 on Android so UAE4Arm seems to be doing something differently that needs to be adopted if possible.
 
One question. on some android tablets, its possible with a patched system to have 50hz from the LCD (e.g JXD S7800B and a few others)? Would be nice if possible (and have access) to be able to perhaps have the 50hz mode as well somewhat?
 

Site & Scene News

Popular threads in this forum