Feature Request: Variable emulation speed

[Warcon]

Right now, as I see it, there is two levels of "emulation speed" supported by 1964:
- N64 speed: This mean that the emulator try to regulate its speed to run at 100% of the speed of a real N64. If the PC is fast enough, the FPS is "stable" at about 50 or 60 fps.
- PC speed: This mean that the emulator doesn't regulate at all the speed and let the emulator run as fast as the PC can support.

What would be nice to be able to modify the emulator to run at a variable percentage of a real N64 (i.e. 50%, 60%, ..., 200%). By exemple, playing SM64 at a "stable" 150% speed might be fun, even if the sound might be screwed a little bit at that speed (instead of an unstable 400% like my PC speed give me right now ).

From what I understand, this is more or less what is done to regulate the speed of the emulator:

for each frame:
A) timestampBeforeFrame = QueryPerformanceCounter();
B) Run emulator until it get a VI interrupt;
C) wantedFps = vips_speed_limits[...]; // Ex. 50.0fps
D) nbMillisecondsBetweenFrame = 1000 / wantedFps; // Ex. 1000 / 50 = 20ms
E) Wait until (PC clock >= timestampBeforeFrame + nbMillisecondsBetweenFrame)

Only the step D) would need to be modified to something like this:

D) nbMillisecondsBetweenFrame = 1000 / (wantedFps * percentageWanted); // Ex. 1000 / (50 * 150%) = 13,33ms

I don't think it would be too hard to do, the time to create the user interface (menu, dialog box, shortcut +/- 10%) for the feature would probably take most of the time.

Anyway, that not an essential feature but, if you got time to implement this, it could be fun ...

Warcon

 

[The Khan Artist]

I, for one, would really like to be able to play at about 25% speed, to see if there actually is a bonus in Super Smash Brothers for killing the Polygon Team in order, like there is for the Yoshies and Kirbys (Kirbies?).

 

[james.miller]

ive been asking for this for a long time. it is very handy. for example i like playing the racing games on the psx at 70-75fps rather than the usual 50 or 60 - it makes the game so much more fluid and ultimatly more fun.

 

[Rice]

And will you be happy with out-of-sync and choppy audio at such speeds?

 

[james.miller]

even if its not perfect, its there to play with

 

[rico001]

variable speed audio?

I was wondering if it would be possible to not emulate music for N64 like on the psx emu when you can play just sound fx?

Or could you make the sound variable.

 

[Doomulation]

The thing is, if the sound is perfect while the gameplay speed isn't, it gets out of sync, just as that.
But...I'm sure your "prayers" have been heard. You'd just have to wait...there's nothing else you can do now, anyway.

 

[karth95]

like doom said.. Rice read it, that's as good as it gets in having the authors hear the request.

The only reason I feel compelled to comment is that from the many discussions I've seen recently, nintendo 64 audio is 100% dependant on being synched to the cpu to function correctly. I don't know if it goes both ways, but either way, your audio is going to suck if you aren't running at a synched speed.

 

[schibo]

If the feature is valuable enough to you to make a donation, it will be considered. Otherwise, we will remain on our normal track.

 

[The Khan Artist]

Frankly, I say screw the audio. The same thing happens in GBA emulation, I normally just turn my speakers off when playing at slow speeds.

 

[karth95]

For me, a lot of the games are fun, but I am really looking forward to hearing the audio as it was meant to be played. The audio just makes the experience so much better.
Picture it, in an arcade... Machines standing there, silent players moving joysticks and hitting buttons, no sounds, no victory bells or shrieks of defeat... it makes the experience, really. A video game without sound feels like pro wrestling without sound.

 

[The Khan Artist]

Sure, if I'm playing the game at normal speed, I want good sound. But if I purposely slow the game down to do a really hard part, I don't particularly care.

 

[karth95]

well, I'm going to have to eat some words here, cause mupen64 0.3 has the speed up/slow down feature and it's sound works quite well.

 

[Doomulation]

Yep, strange enough. Although I knew even before it was released, errr...well, anyway, thank Hacktarux for it and have fun with it.

 

[GE Master]

I think that having a variable speed setting is important. Of course I say this because some games lag on the N64. Think of Perfect Dark with a ton of sims...there is substantial lag or "chugging". The beauty of being able to increase the speed is obvious in these situations. From a GoldenEye perspective, levels that weren't playable like the Archives Backzone, can be very playable with a better frame rate. I see a feature like this pushing the N64 beyond what the console was capable of. Maybe I'm on glue thinking that something like variable speed is possible in N64 emulation. Can Rice comment on that?

 

[zorbid]

And will you be happy with out-of-sync and choppy audio at such speeds?

Unless you modify the sampling rate as well...

 

[schibo]

If gameplay is choppy when a lot of enemies are in the game, lower the CF timing. Timing is one of the more quirky things emulation.