If a New PSP Emulator Will ever be made , what do you think of the Req?

shashClp said:

Apply the usual 10x-20x rule for a console that has, to say the least, two 333Mhz cores (the Allegrex and the ME). Then start adding for the GPU and else, and you've your answer.

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I don't like those multiplier "rules" that people often mention, and I think that you don't actually agree with them yourself but are using them as a simplification for people who won't understand more technical explanations. But I think they've caused a lot of bad information and confusion in scenes.. usually people will pick whatever number justifies the context, so you might see 5x or 7x or 10x or 30x or whatever. Of course you already know everything I'm going to say so I'll say this for the benefit of other readers. Also, I've made posts like this before so if it starts to sound familiar you can just skip past it.

The problems with the rules are that for one thing, you can't just attribute a number to how "powerful" a platform is. People often come up with something based on clock speed of the main CPU, and as everyone knows different CPUs are capable of doing different amounts of "work" per cycle. More importantly, a platform will often have components that do more "work" than the CPU does. These are often ignored entirely, or at least not really well understood.

Another problem is that it doesn't address how good of a fit the "hard working" parts of the platform are for being emulated on another platform. Sometimes you can have a really intensive hardware operation that can be emulated really well because what you're emulating it on has equivalent hardware function. Other times things that are relatively simple in their original hardware implementation end up costing a ton of time to emulate because the CPU emulating it is not good at dealing with it. Take for example emulating floating point. If the platform you're emulating has fully IEEE754 compliant floating point and you're emulating it on a platform that also has fully IEEE754 compliant floating point, and there are otherwise no deviations, then you can emulate it really well. If, on the other hand, floating point implementations are incompatible (or the thing you're emulating on doesn't have floating point) then it's a totally different story, and now the operations take several times longer.

Finally, it depends on how the games are writte and what the goals of the emulator are. If the games require really tight timing then it could require a really slow emulator that's constantly switching between components it's currently emulating. Maybe only a small percentage of games need this, then it depends on how much performance the emulator author wants to sacrifice for compatibility. A lot of emulator authors shoot for high accuracy regardless of what games do, some just want to get the most popular games working well and will employ hacks to help them run better or faster.

In the case of PSP, there's a lot of potential for high level emulation. hlide, someone who knows more about PSP emulation than most others because he has worked on it extensively now, believes that PSP emulation may be meaningfully realistic on platforms that are much less powerful than current high end PCs. Even though PSP has a lot of hardware, a good deal of it isn't directly accessible to games - really only the CPU (and FPU/VFPU) and GU. The graphics map decently to high level 3D operations that a 3D card can. A lot of games won't be pushing the CPU anywhere near its limits and because of the abstracted nature of the platform will probably be yielding to the OS when they don't need CPU time. Especially when considering that many games aren't even clocking the CPU at 333MHz you'll see that many things won't really require heavy CPU emulation. Also, the abstracted nature of the device means that less overhead has to go into emulating the CPU because the memory accesses it can make are simpler and you don't have to count cycles.

an0ny said:

does it play most of the games?

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or go to the link I posted >.>

an0ny said:

men that emu sucks

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nope, it's very promising.