What About A Ds Emulator?

[borgqueenx]

While I'm here, I might as well ask, is it possible to use Pandora hardware directly for emulation? I.e. telling the games to use the Pandora touchscreen instead of 'tricking' them into 'thinking' it's a DS touchscreen?

Sorry, but your question doesn't make any sense. People have really strange conceptions as to what emulation is and isn't. There's no "using" vs "tricking" or "running directly" vs "emulating", these are all just different words to describe the same thing.

People seem to look at this as something black and white - either it can be done or it can't, and this is something that's just known upfront. The reality is that no one knows how well an "optimal for Pandora" DS emulator would perform because such a thing doesn't exist. The well informed can make estimations, but they're still missing so much data that there wouldn't be an awful lot of confidence behind such a thing. This would also only be reflecting worst cases, because there isn't a good understanding of exactly what DS games do on average.

The current idea people seem to have, judging from this thread, is that it can be done (whatever that means, we'll assume to some satisfactory level), but it'll just take a lot of time and skill. In reality we can't know this. On the opposing end, a lot of people say it can't be done. We can't know this either. I think saying either thing is counter-productive and dangerous, but I'd rather people believed the former than the latter.

Listen to this man. When people said there was no way GBA could be emulated at a playable level on the PSP, he proved them wrong by doing it. So believe what he says folks, no good may come from Exophase, but the truth does.

basicly, we need exophase to work on the DS emulator

 

[ahahah]

You want to EMULATE A DS? YOU FOOL! Your preorder is canceled!

hihihihi^^

Screen layout has NEVER been an issue.

huh? :huh:

Where will you insert the nds game cartridge

not necessary for comercial games, but for homebrews (they are doawnloadable, they are files no need cartdridges)

For right now just assume that it's not possible. DS emulation requires a lot of resources, probably more than people realize.

pandora is more powerful than a psp, isn't it? :huh:

 

[calc84maniac]

Screen layout has NEVER been an issue.

huh? :huh:

Just about everybody who thinks they have an amazing idea of how to get DS emulation to work comes in posting how the screens can be arranged, as if that will magically allow the emulator to work. It's been discussed a dozen times before.

For right now just assume that it's not possible. DS emulation requires a lot of resources, probably more than people realize.

pandora is more powerful than a psp, isn't it? :huh:

But the PSP wasn't running that DS emulator at any respectable speed, now was it? There's no way to know whether the Pandora has enough extra speed to get it playable until someone tries.

 

[WizardStan]

pandora is more powerful than a psp, isn't it? :huh:

Did you just hear that there's a DS emulator for the PSP, or did you actually try it?
Just because it runs doesn't mean it runs WELL. Which it doesn't, it runs very poorly. Yes, the Pandora is more powerful* than the PSP, but all that means is a DS emulator will run less poorly than on the PSP. It could still be completely impractical to do. Or maybe some clever coder steps up and manages to make it work, but a lot of work it will be.


*and the first person to say "clock rate doesn't equal power" or anything similar will have their order canceled

 

[Jourdy288]

While I'm here, I might as well ask, is it possible to use Pandora hardware directly for emulation? I.e. telling the games to use the Pandora touchscreen instead of 'tricking' them into 'thinking' it's a DS touchscreen?

Sorry, but your question doesn't make any sense. People have really strange conceptions as to what emulation is and isn't. There's no "using" vs "tricking" or "running directly" vs "emulating", these are all just different words to describe the same thing.

People seem to look at this as something black and white - either it can be done or it can't, and this is something that's just known upfront. The reality is that no one knows how well an "optimal for Pandora" DS emulator would perform because such a thing doesn't exist. The well informed can make estimations, but they're still missing so much data that there wouldn't be an awful lot of confidence behind such a thing. This would also only be reflecting worst cases, because there isn't a good understanding of exactly what DS games do on average.

The current idea people seem to have, judging from this thread, is that it can be done (whatever that means, we'll assume to some satisfactory level), but it'll just take a lot of time and skill. In reality we can't know this. On the opposing end, a lot of people say it can't be done. We can't know this either. I think saying either thing is counter-productive and dangerous, but I'd rather people believed the former than the latter.

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

 

[borgqueenx]

While I'm here, I might as well ask, is it possible to use Pandora hardware directly for emulation? I.e. telling the games to use the Pandora touchscreen instead of 'tricking' them into 'thinking' it's a DS touchscreen?

Sorry, but your question doesn't make any sense. People have really strange conceptions as to what emulation is and isn't. There's no "using" vs "tricking" or "running directly" vs "emulating", these are all just different words to describe the same thing.

People seem to look at this as something black and white - either it can be done or it can't, and this is something that's just known upfront. The reality is that no one knows how well an "optimal for Pandora" DS emulator would perform because such a thing doesn't exist. The well informed can make estimations, but they're still missing so much data that there wouldn't be an awful lot of confidence behind such a thing. This would also only be reflecting worst cases, because there isn't a good understanding of exactly what DS games do on average.

The current idea people seem to have, judging from this thread, is that it can be done (whatever that means, we'll assume to some satisfactory level), but it'll just take a lot of time and skill. In reality we can't know this. On the opposing end, a lot of people say it can't be done. We can't know this either. I think saying either thing is counter-productive and dangerous, but I'd rather people believed the former than the latter.

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

good option.
What about PS3 emulation, on hardware ofcource?

 

[fischju2000]

While I'm here, I might as well ask, is it possible to use Pandora hardware directly for emulation? I.e. telling the games to use the Pandora touchscreen instead of 'tricking' them into 'thinking' it's a DS touchscreen?

Sorry, but your question doesn't make any sense. People have really strange conceptions as to what emulation is and isn't. There's no "using" vs "tricking" or "running directly" vs "emulating", these are all just different words to describe the same thing.

People seem to look at this as something black and white - either it can be done or it can't, and this is something that's just known upfront. The reality is that no one knows how well an "optimal for Pandora" DS emulator would perform because such a thing doesn't exist. The well informed can make estimations, but they're still missing so much data that there wouldn't be an awful lot of confidence behind such a thing. This would also only be reflecting worst cases, because there isn't a good understanding of exactly what DS games do on average.

The current idea people seem to have, judging from this thread, is that it can be done (whatever that means, we'll assume to some satisfactory level), but it'll just take a lot of time and skill. In reality we can't know this. On the opposing end, a lot of people say it can't be done. We can't know this either. I think saying either thing is counter-productive and dangerous, but I'd rather people believed the former than the latter.

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

You mean virtualization, executing the same code as the DS would on it's ARM CPUs on the Pandora's ARM rather than recompiling it. It's been discussed pretty thoroughly in some of the previous DS emulation threads (by Exophase most of the time) http://www.gp32x.de/board/index.php?/topic/50198-virtualization/

 

[calc84maniac]

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

You mean virtualization? Don't even get Exophase started on that

 

[hal9000]

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

Sorry, but you aren't. It seems that what you are saying makes no sense at all. If you know something about how emulation is actually working, could you describe more precisely what you think hardware-based emulation is?

EDIT: Sorry, my post sounds a bit rude, it was not intended.

 

[conso]

lol. I heared the ps3 runs linux, too and it has openGL ES! HLE should be trivial.

Back on topic: I still think exophase is tinkering with DS-emulation at times. Does anyone remember how long he had announced gpSP before he made the first release?

 

[Jourdy288]

What I'm trying to say is this: What about hardware based emulation? I'm really hoping I'm using that term right....

Sorry, but you aren't. It seems that what you are saying makes no sense at all. If you know something about how emulation is actually working, could you describe more precisely what you think hardware-based emulation is?

EDIT: Sorry, my post sounds a bit rude, it was not intended.

As the below posts went into, it's called virtualization, I'm going to have to research how that works.

 

[Exophase]

Even if virtualizing the CPUs is possible it doesn't address several other hardware components.

All in all this is what you have to emulate:

ARM9 CPU at 66MHz
ARM7 CPU at 33MHz
2x 2D graphical engines that are each more powerful than GBA and are higher resolution; in graphical emulation cost scales with resolution, especially scanlines.
Geometry engine capable of doing a ridiculous (for the scale of the rest of the device) number of geometry and lighting calculations per second, all in high precision fixed point (more significant bits than single-precision floating point)
3D engine with a lot of weird effects, that combines per-scanline with the 2D output
16-channel ADPCM audio engine

The way I see it, there are some obstacles to using the SGX to help with 3D. One is that OpenGL ES 2.0 can't accomplish some of the features like a DS would, or can't do it at all, including:

- Pre-load depth from a bitmap, OGL ES 2.0 can't do this at all w/o depth texture extensions with SGX doesn't currently have
- Fogging control per-pixel, the only way to do this would be with expensive multipass stencil techniques
- Stenciling might not be sufficient for shadowing because there's a conflict between opaque and alpha IDs, this also goes for alpha overlap
- Edge detection requires export of opaque ID + depth for postprocessing; if OpenGL ES 2.0 let you read back depth and stencil then maybe something could be done but it doesn't (w/o extension SGX doesn't have), and it doesn't support multiple render targets either so to get the necessary information you need at least a second pass including shuffling the geometry back
- W-buffering is available on DS and not on OpenGL ES 2.0; for depth compares this may be a wash since Z-buffering is 16bit on DS and W is 24-bit, SGX is 32-bit floating point regardless, but this could have an impact on fogging calculations.
- DS can change render state pretty much between every primitive if it wants to, without a substantial amount of overhead. If a game tries to do anything even close to this it'll kill the SGX.
- Since the screen is combined with 2D which is rendered in software (rendering it in hardware is not really an option either) the framebuffer has to be continually read back. All indications suggest that even with FBO renderbuffers the performance of glReadPixels is poor.

The alternative, to render 3D in software, has another major obstacle: DS is perspective correct (both texture coordinates and colors, although I'm not 100% convinced on the latter), which means a division is necessary for every rendered pixel. NEON can do this sort of fast, but the problem then is that you have to perform loads from the NEON registers, which means transferring them to ARM registers, which is also very slow. Maybe with some multi-pass buffering this could work, but on DS polygon scanlines probably get pretty small a lot of the time, so there might not be a huge potential for buffering spans.

All of this is done at 60Hz on DS, not like the usually <= 30Hz on N64. But that also means that frameskipping will win you much more up front, at a lower visual degredation.

 

[Jourdy288]

OK, thank you. This is just what I needed to know.

 

[ahahah]

Just about everybody who thinks they have an amazing idea of how to get DS emulation to work comes in posting how the screens can be arranged, as if that will magically allow the emulator to work.

thanks for the sarcasm... <_<
i've never thought i have an "amazing" idea
i've never thought that speaking about the arrangement screen will have an influence on the performances of the emulator
at last i've never thought the words written on a forum will "magically" act on a project.

 

[x68000]

By my calculations, we need to get the Pandora overclocked to 800Mhz for playable DS Emulation............ :rolleyes:

 

[mcobit]

By my calculations, we need to get the Pandora overclocked to 800Mhz for playable DS Emulation............ :rolleyes:

Maybe we shouldn't talk that much about overclocking right now...

 

[x68000]

By my calculations, we need to get the Pandora overclocked to 800Mhz for playable DS Emulation............ :rolleyes:

Maybe we shouldn't talk that much about overclocking right now...

I think we should:

http://www.gp32x.de/board/index.php?/topic/52157-frying-an-arm-chip/

 

[Poem58]

By my calculations, we need to get the Pandora overclocked to 800Mhz for playable DS Emulation............ :rolleyes:

Somehow, I knew this was coming... :blink: ...lol

Also, it still amazes me when someone mentions some system and a dev like Exophase just busts out all this technical stuff that while I kinda get, for the most part could be made up gibberish and it would still impress the hell out of me. Just amazing that people not just know about this stuff, but know it this well.

 

[Exophase]

By my calculations, we need to get the Pandora overclocked to 800Mhz for playable DS Emulation............ :rolleyes:

Please don't do that, someone is going to miss the reference and think you're serious

 

[x68000]

I think we need some light hearted banter right now after the events of today.


To the confused, 800Mhz OC was a reference to the crazy thread that transpired earlier.