Slowdown in games MegaAGS/WHDload/ADF

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buttersoft
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Slowdown in games MegaAGS/WHDload/ADF

Unread post by buttersoft »

I was playing around with Lotus Esprit Turbo Challenge the other day and noticed that there's a ton of slowdown in the intro, when the music is playing and it demos the in-game driving. I was loading from MegaAGS, and tried both PAL and NTSC modes, adjusting all sound and video options (the latter having to stay at 15kHz for my direct video setup). I also tried changing from an A500 to an A1200 but it made no difference. The only thing that might have made things worse was losing chip RAM but i'm not sure.

I then tried loading the game from my own HDF images, and performance was improved a bit, but still a long way from perfect.

Loading from ADF was better still, and almost perfect. But there's still a tiny bit of slowdown creeping in.

All versions seemed to play at full speed in game without problems (or 6/5 speed for NTSC) the slowdown only happen in the intro. I have not yer compared with real hardware, but i should do that too.

So, is there anything that can be done about the slowdown? I would guess it's something at least in part from the core, given the ADF version isn't completely perfect. But i'm no VHDL expert and don't want to impugn the efforts of others in this community to whom we are all indebted. Just looking for clarification and any possible workaround.

(also, where is the MegaAGS project located, how do i find newer versions? Any help appreciated!)
akeley
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Re: Slowdown in games MegaAGS/WHDload/ADF

Unread post by akeley »

I've checked it against WinUAE and it seems to have the same behaviour - slowdown only in that particular part in attract mode, when the racing starts, more prominent via WHD than in adf. I think it's safe to say it's just an in-game coding issue, since everything else seems fine, amplified by WHDLoad, which is also normal sometimes. I could check it on my real A500 to be 100% sure but it went off my desk rotation just yesterday and I'm too lazy to drag it out again.

For MegaAGS check "htgdb-gamepacks" on archive.org. Not sure if it's always the the latest one, but they seem to be fairly up to date.
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Re: Slowdown in games MegaAGS/WHDload/ADF

Unread post by buttersoft »

Roger, thanks for the testing. I'm the same with my A500. It's sitting there but i have to connect it up :)

I think I'd found that megaAGS pack, but i have no idea who's producing them and it would be nice to know.
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