Yabause-dc News (and 0.0.7 release!)

abydos1000 · Post by **abydos1000** » Mon Jan 24, 2005 3:55 pm

never got past the black screen. likely I did something wrong. Still, I applaud your efforts.

jessman · Post by **jessman** » Wed Jan 26, 2005 8:38 pm

(OFF-TOPIC) man! why is the saturn taking so long to get good emulators? BTW, I'm not talking about Dreamcast-wise, I mean in the pc world. I realise that it's hardware is more complex than the psx, but SHEESH! Playstation emulation is basically perfect now. Well, anyways, it's good to see someone trying to contribute to the scene with a unique emulator. thank you for giving us hope for the future.

Post by **Quzar** » Wed Jan 26, 2005 8:43 pm

two things:

1) saturn wasnt as popular, so not only did less people have it, but there was less of a drive to reverse engineer the hardware, and to write software related to it.

2)like you said, the saturn was more complex. On top of that, it is much more powerful (in the raw combined power of the CPUs), so not only was there little drive and little resources for the creation of an emulator, but even if there had been good drive, it would still be something far off.

Link2k4 · Post by **Link2k4** » Wed Jan 26, 2005 9:54 pm

may I ask how is it possible to emulate it on a DC, its kinda pointless to emulate it if it can't get at a barely playable speed. I am not putting down blue crab or his work, I am just saying how can you emulate something THAT complex with a 200 mhz machine?

Clessy · Post by **Clessy** » Wed Jan 26, 2005 10:45 pm

They're the possablity of DC exclusive speed ups to do similar hardware. Saturn having a Sh2 and DC having a Sh4.
Plus with optmization saturn could be runing on 500mhz pc. psx ran fine on 300mhz pc via bleem.

Post by **Quzar** » Wed Jan 26, 2005 10:47 pm

Link2k4 wrote:may I ask how is it possible to emulate it on a DC, its kinda pointless to emulate it if it can't get at a barely playable speed. I am not putting down blue crab or his work, I am just saying how can you emulate something THAT complex with a 200 mhz machine?

On a PC one of the biggest reasons that it takes such a fast processor (1ghz at least) to run a saturn emulator is the sh-2 processors, as they each run fairly fast. (try running ST-V games in mame and see how slow they play). On the DC, its possible to get a little under 1:1 speed on the sh-2s as the instructions are the same and the only difference is the endian-ness of the processors.

Link2k4 · Post by **Link2k4** » Wed Jan 26, 2005 11:29 pm

quzar wrote:
Link2k4 wrote:may I ask how is it possible to emulate it on a DC, its kinda pointless to emulate it if it can't get at a barely playable speed. I am not putting down blue crab or his work, I am just saying how can you emulate something THAT complex with a 200 mhz machine?
On a PC one of the biggest reasons that it takes such a fast processor (1ghz at least) to run a saturn emulator is the sh-2 processors, as they each run fairly fast. (try running ST-V games in mame and see how slow they play). On the DC, its possible to get a little under 1:1 speed on the sh-2s as the instructions are the same and the only difference is the endian-ness of the processors.

I am guessing it would emulate 2d very well, could you possibly give me a rough estimate is to how many FPS would the emulator do on DC? I am guessing maybe 15.

Post by **Quzar** » Wed Jan 26, 2005 11:33 pm

it is ridiculous to try to judge something like that at this point. not only that but useless.

Link2k4 · Post by **Link2k4** » Wed Jan 26, 2005 11:52 pm

I was just stating something and asking for a guess, don't get all bent out of shape.

Post by **Quzar** » Thu Jan 27, 2005 12:23 am

Link2k4 wrote:I was just stating something and asking for a guess, don't get all bent out of shape.

no, i was being literal. there is no way to make a guess at this at all. especially since the PC version of the emulator still cannot play any games.

Clessy · Post by **Clessy** » Thu Jan 27, 2005 5:54 am

Link2k4 you wanted a number? 18. Sure I pulled it out of my ass and it is in no way accurate but at least you have a number to comfort you.

abydos1000 · Post by **abydos1000** » Thu Jan 27, 2005 7:57 am

Well, before the topic gets locked by feistiness, for reasons that quzar has already stated, due to SH4 versus SH2, the instructions are virtually the same so full speed may be possible one day. I'm not a programmer, but probably one of the biggest challenges will be emulating everything else. The Saturn was pretty complex compared to the PSX. I imagine if someone had the patience to write key parts of the emulator in SH4 assembly, that would speed things up (example, SNES9X was ported to the mac in PPC assembly so even a 10 year old Mac can play super nintendo games). So to your question as to how can a 200 mhz dreamcast run a saturn emulator will rely on a number of things. Of couse, comparing the clock speed of different chips is pointless.

Post by **BlueCrab** » Thu Jan 27, 2005 9:23 am

Yeah, speaking of Dreamcast-specific optimizations (since everyone likes throwing that around today), here's my list of todos for Yabause-dc:

1) Optimized SH2 CPU core - Preferably a dynarec of sorts, basically just reversing the endianness.
2) Optimized VDP1 - The Saturn's VDP1 is in many respects very similar to the PVR in the Dreamcast, I must make use of the similarites.

That's what's on my list right now, hopefully after the first is done (which will take a while, believe me, cpu emulators are no easy task to write) things will move along much faster.... hopefully.

To Link2k4: Actually, the 2D parts of the saturn are a lot more complex to emulate at any sort of speed. And the main reason I even started on porting yabause was to see if it was possible to emulate the Saturn on the Dreamcast. I truly don't know what the future holds, but I doubt that alone I'll be able to get full speed. Who knows, only time will tell on that one.

Alexvrb · Post by **Alexvrb** » Thu Jan 27, 2005 3:14 pm

Clessy wrote:They're the possablity of DC exclusive speed ups to do similar hardware. Saturn having a Sh2 and DC having a Sh4.
Plus with optmization saturn could be runing on 500mhz pc. psx ran fine on 300mhz pc via bleem.

Bluecrab has some hope of seeing something playable on Dreamcast because of the kind of developments he proposed here. You're not going to get remotely accurate AND playable Saturn emulation on a 500Mhz PIII or Athlon, even if they wrote excellent asm cores. There's just too much to emulate.

Clessy · Post by **Clessy** » Thu Jan 27, 2005 5:48 pm

Alexvrb wrote:
Clessy wrote:They're the possablity of DC exclusive speed ups to do similar hardware. Saturn having a Sh2 and DC having a Sh4.
Plus with optmization saturn could be runing on 500mhz pc. psx ran fine on 300mhz pc via bleem.
Bluecrab has some hope of seeing something playable on Dreamcast because of the kind of developments he proposed here. You're not going to get remotely accurate AND playable Saturn emulation on a 500Mhz PIII or Athlon, even if they wrote excellent asm cores. There's just too much to emulate.

I don't know why people care about accuracy out emulation so much . Its all about the output. Even if it uses hacks and speed tricks it doesnt matter.

OneThirty8 · Post by **OneThirty8** » Thu Jan 27, 2005 8:36 pm

Yeah, but if you use hacks and speed tricks left and right in order to get playable speed, won't you likely have problems with compatibility left and right as well?

Skynet · Post by **Skynet** » Fri Jan 28, 2005 6:07 am

And noobs saying "omg teh saturn emulat0r is teh suxxorz!"

Clessy · Post by **Clessy** » Fri Jan 28, 2005 11:01 am

OneThirty8 wrote:Yeah, but if you use hacks and speed tricks left and right in order to get playable speed, won't you likely have problems with compatibility left and right as well?

Depends what type of hacking you do. Like older emulators didnt emulate the music they tried to synasize it instead of really fully emulating the sound. Gencryst orginally did that. Also some hardware doesnt require perfect timing and accuracy to run its games perfectly. Sega Master system for example. Underclocking can break games but if you make charts per game it can be used to speed each game up on its on indepentand lv. Also with sound you can make it output a low quality then what the actual hardware would.

Ohh and to the noobs thing. Noobs don't give a shit how its done they just want it to run fast. And tricks are the way to get things to run fast.

Alexvrb · Post by **Alexvrb** » Sat Jan 29, 2005 12:10 am

I said remotely accurate AND playable. Meaning something that can actually play some games, and at a reasonable speed. I'm sure you'd like to show Bluecrab how to implement "teh trickz0rs". :/

Link2k4 · Post by **Link2k4** » Sat Jan 29, 2005 12:26 am

BlueCrab wrote:Yeah, speaking of Dreamcast-specific optimizations (since everyone likes throwing that around today), here's my list of todos for Yabause-dc:

1) Optimized SH2 CPU core - Preferably a dynarec of sorts, basically just reversing the endianness.
2) Optimized VDP1 - The Saturn's VDP1 is in many respects very similar to the PVR in the Dreamcast, I must make use of the similarites.

That's what's on my list right now, hopefully after the first is done (which will take a while, believe me, cpu emulators are no easy task to write) things will move along much faster.... hopefully.

To Link2k4: Actually, the 2D parts of the saturn are a lot more complex to emulate at any sort of speed. And the main reason I even started on porting yabause was to see if it was possible to emulate the Saturn on the Dreamcast. I truly don't know what the future holds, but I doubt that alone I'll be able to get full speed. Who knows, only time will tell on that one.

Thanks, Blue crab,I am glad you cleared it up. I hope you can pull this off. I will be rooting for you now and in the future. :}