dreamcast discussion

[CyRUS64]

Now that i've registered just to appease martin (j/k), we need some more interesting dreamcast emulation related discussion around here =)
Come on, someone must be interested! Ask anything u like...
Otherwise I might aswell just stop work on Icarus right now

CyRUS

[blizz]

Nooooooo keep going

[Martin]

Yeah, hmm.

How far are we from emulating commercial games? (Dreamemu and Icarus especially come to mind).

[Redah]

How would you emulate it? Would it read ISOs downloaded from the Internet? Could my CDROM drive read the GDROM discs?


:colgate:

[Slougi]

When will we have a 100% compatible DC emu that runs on a P1 133 Mhz with 8MB ram and a 1MB generic gfx card? J/K

What will you be working on next? Are u considering using plug-ins for gfx and sound as in n64 & psx emulation?

[CyRUS64]

I'm sure u will see some sort of display from commercial games - namco museum does a fade effect for example already - but getting commercial games displaying at anything acceptable will take a long long time. The powervr2 chip uses weird rendering methods and polygon types, that just arent comparable to other graphics chips. (eg: what the hell are volume modifiers and punch-thru polygons =) )
There is also the problem of emulating the gdrom dma for loading data from disk (virtual disks in my emu of course, NOT real gdroms), and lots of other more serious problems are bound to arise.

I'll personally keep working on katana samples, and once a variety of those (rather than just the kamui gfx api ones which ive worked on thus far) are running, then I can look into commercial emulation.

[CyRUS64]

redah: yes it would have to read isos downloaded from the internet. There was once some guy who claimed to have hacked linux to read gd-roms but I dont think it is technically possible to read them with a standard cd/dvd drive. I dont know enough to say for sure.

slougi: working on next? this is a life-time project i expect I also do work on a gameboy emu for dreamcast whose first new version for half a year will be solely dev'ed using icarus (hopefully at least). I dont have much time for it atm.

With regard to plugins, im not particularly fond of them. I almost prefer each emu having a uniqueness to it. I will probably have an optional gfx plugin spec so that external authors can make a plugin for icarus, but it probably wont be compatible with any other dc emus, just cuz there arent any around in active development that are at the same stage as me. If anyone who is skilled at 3d graphics and really wants to start on one now (and is serious+comitted), then they can always come visit me in #boob/#dcdev on efnet, and we can arrange something.

[Remote]

Is it mainly graphic emulation that is keeping you from progressing? What parts are / aren't emulated and what parts do you find especially hard to emulate?

[Slougi]

Originally posted by Slougi
What will you be working on next?

I meant if you will be focusing more on gfx, sound or cpu stuff for the time being.

[CyRUS64]

Remote: those samples are complete other than rendering so yes, that needs working on. as for everything else there is a hell of a lot of work to be done on the rest of the dc
As for commercial games it is gdc dma as explained in an earlier post that is halting them from getting further. I have to basically sit down and start reversing lots of the unknown commands used.

Slougi:not sound, but everything else. I want to get those samples looking better... ie: with textures. Then I'll go back to other stuff... I wont be attempting lighting or odd polygon types such as the volume modifiers and punch-thru polys for a long while though. I may have a play with sprites though cuz some demos do try and use them...
As for sound, the emu does already contain a modified (dc arm has some differing instructions and doesnt have thumb mode for instance) boycott advance arm core (thanks to Julien!) and it does execute ops and will run happily, but it is currently disabled by default and I just use my FakeARM (tm).
This doesnt mean sound is heard at all atm btw, since the dc has a third processor which is the sound synthesiser, the arm just communicates between this (an aica chip) and the sh4.

CyRUS