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Re: Nice demo, but why does it die?
THe one thing I'd like to say in response is that:
Liken and Quorum both have to emulate the processor, like SoftPC. The NeXT
on the other hand has a 68K family processor. So instead of emulating the
whole processor you grab the graphics and system calls. This is a lot different
than SoftPC and the emulation of a PC on NeXT hardware. This is the big reason
that SoftPC is slow. It not only has to emulate the processor but it has to
intercept graphic calls to the bios and hardware. A much more difficult job
than what's done in Executor. Liken is the same in that respect.
I would say that Executor is more in the same line of emulators for the Mac that
run on the Amiga and Atari, that is same family of processors so instruction
set mapping or emulation is not needed.
I understand that for the Atari and Amiga you need the ROMS, etc.
I'm not trying to take anything away from Executor, I think it's a great
program. But I also think that SoftPC and Liken were more difficult to write
just because you have the added difficulty of supporting the native processor
that the stuff originally ran on through software.
I've written a software emulator for a vector processor for a PC. This
included all registers and a couple of vectored interrupts. Ran fine, but it
was a pain to support interrupts.
I hope you see my point.