Fan-made tech demo of Starfox on the Genesis

[FuturePrimitive]

Game on!

[sheath]

Yeah, I'm watching the video again, it is possible we are seeing regular jail bars in the cut scenes but not during actual gameplay. Where I was coming from was this:

Duke Nukem Emulation:


Real Hardware:

[sheath]

Oh yeah, this was mentioned but not emphasized enough I think.

ResQ's Bonus rounds:

[djshok]

^ That

[Iron Lizard]

That place looks really shitty. They sound as bad as some the forums I'm on. I forget how awesome this forum is sometimes.

[Barone]

Once I thought AtariAge was bad; but then we got NintendoAge, "the real deal". At least, AtariAge has tons of useful information for Atari consoles owners/collectors, can't say the same about NA.
Oh, well...

[Thunderblaze16]

One thing I really enjoy about Nintendoage is that you can sell stuff really quick, unlike here but man. I always see at least 1 or 2 threads a week talking about game prices going high, what games well increase next, why games are so rare now and why do you still collect.

[john8248]

Awesome job, Stef! Sent you a PM that's kind of, sort of about this demo.

[tim333]

This demo is very cool, but I don't get kicking sand in NintendoAge's face (or, to be fair, some of their responses). What's the point, in 2013, of arguing SNES vs. Genesis? Surely that rivalry belongs in the past.

[kool kitty89]

Edit:
Also, it's interesting to note a lot of reasonably level headed comments in the Nintendo Age thread . . . and several complaining about 3GenGames' stupid comment too.

3 Gen Games always makes me laugh, so knowledgeable

9fps does sound pretty rough

Dude, it's a fucking demo. Can't you ever post anything that isn't negative about someone elses work?

Thanks for all kind comments I wanted to keep it private as it's still very preliminary, even for a simple demo... and I would have never imagine it could arrive here that quickly but anyway, here is the idea, we can do something close to the SNES Starfox on a stock genesis
The demo can be optimized in some way, i am really close to the original data structure format as i ripped them from the rom directly. For instance all the palette sub system use directly original rom data and code logic without any conversion. The original structures are heavily optimized for the SNES (many of byte stuff) so we can really do better if the made was made from scratch for the MD for instance

This is something I've wondered for a while, but:
Are all the objects in Star Fox rendered in realtime, or are some prerendered 2D vector animation that just gets rasterized? (and I don't mean the scaled/rotated sprite textures, since those are obviously 2D)

Also, are the polygons being rasterized with any compensation for aspect ratio, ore are square pixels assumed? (I forget if the SNES game bothers with this either) Running in H40 might be interesting, though you'd have a bigger horizontal boarder then, but squarer higher-res pixels and more DMA bandwidth. (maybe get away with double wide pixels -bytes rather than nybbles- without being too jagged -if you tried doing that in H32, it would be more obvious, though you could blur things a bit using H-scroll -shifting 1 pixel left/right at 60 Hz to blur things horizontaly)

It will probably help but the software bitmap engine will never go higher than 20 FPS (NTSC) or 25 FPS (PAL) so that is a strict high limit.
What is bad on real hardware is the infamous vertical cell scrolling bug which affect the first column :-/

Can you scroll the screen over to hide the cell scroll artifacts?

Indeed it does run a bit slower than on real SNES but not that much.
Starfox on SNES runs at variable frame rate, oscillating between 7 FPS on heavy scene up to 14/15 FPS on empty ones.
I still have some rooms for optimization and i think i can do something close to the SNES version.
Considering we do not cheat as the SNES that is not that bad, thanks to the blast processing

It hits 7 FPS with a lot more going on than your demo though, but again, we'll have to see how things go once the thing gets fully optimized. (I wouldn't be surprised with the MCD outdoing Super FX, but vanilla MD would be really interesting) The most impressive software rendering on 68k I can think of is Geograf Seal running on a 10 MHz x68k. (then again, you've got an 8bpp framebuffer to help there too, and a lot of RAM to help with some shortcuts)

I pretty much agree with you NeoVamp. If a 32X answer to StarFox were needed that game wouldn't have been better than what we already got in Star Wars Arcade, Shadow Squadron and even After Burner and Space Harrier. I did wish the Sega CD had more of a polygonal rail shooter like Star Fox though, but Stellar Fire and Silpheed pretty much delivered on that front.

Still, I wouldn't mind seeing more polygonal games released for the Sega CD that attempted to max out both 68000s and the Graphics CoProcessor, not to mention DMA to the Genesis VDP. Those were the technical feats that I wanted back in 1992-3. Once the 32X came along I was imagining Tomb Raider and Virtua Fighter, not Chip-assisted SNES games.

You probably aren't going to see games "maxing out" both 68ks on the MCD, but a game using the CD CPU to handle all the rendering and math while the base game engine (logic, I/O, etc) runs on the MD would probably work out OK.
Whether you used the ASIC would probably depend on the game. ASIC can only render in 2 Mbit (1-bank) word RAM mode, so it must be halted during VRAM updates, otoh, if you do 100% CPU rendering, you can use 1 Mbit bank mode where you can toggle 2 128 kB buffers between MD and MCD end. (so render with the sub-CPU at full speed and zero waits)
With the amount of texture mapping and scaled and/or rotated sprites in some parts of Star Fox, the trade-offs of using the ASIC would probably be preferable to CPU rendering alone.

The silly gradient could probably be done with the background color trick no problem, not sure if it could rotate tilt too though.

That wouldn't really help. The gradient issue isn't just sub-palette related, but more a problem with 9-bit RGB. You'd need to dither and/or use approximated shades of other colors to do the same sort of green gradient.

Is it even 2x slower? I thought Starfox on the SNES ran at ~10fps. I also laughed at the comment about it being windowed. Did he forget SNES Starfox runs in a 224x190 window?

I'm pretty sure it peaks at 15 FPS, but drops below that quite often. (normally doesn't drop below 10 FPS though) This demo is a lot choppier than the SNES game (average and minimum framerate), but that's not that surprising given it's totally software rendered, running at higher res, and an almost straight port without optimization on the data end. (the geometry and drawing ends are MD specific though . . . that wouldn't work otherwise -MD also has the big advantage of packed pixels . . . might not run this fast on Atari ST for that reason, then again the ST managed to keep pretty close with most 3D games it shared with the MD so maybe not)

Oh yeah, I always found Starfox on ZSNES to be hilarious cracked out:

https://www.youtube.com/watch?v=2q0A-U_n4Mw

I wonder if we could get that level of performance with some help from the SVP chip/Sega CD/32X.

Ugh, I hate older versions of SNES9x and ZSNES for this reason: no frame limit on Super FX games (and, apparently, generally inaccurate VRAM DMA limitations). The game should be capped at 15 FPS, but some emulators run it at 30, and it ruins the feel of the game (not to mention cutting off sound clips in some cutscenes). OTOH, some newer emulators still don't speed limit the Super FX, so you get a solid framerate cap but no slowdown. (which, admittedly, is rather nice . . . sort of like overclocking Super FX on real hardware -some games might be able to use Super FX 2 chips too . . . not slapping SFX2 onto older carts, but swapping ROMs onto Doom or Yoshi's Island -Star Fox 2 style; Stunt Race FX was originally intended for SFX2 iirc, which is why it struggles so much with SuperFX1)

Someone needs to make a request to the Nintendo guys that they see how well they can do getting Starfox up and running on a stock SNES. That's right, no SFX chip.

Different topic: but personally, I'd be interested in seeing how the SNES handled 3D with just a DSP-1 chip . . . the basic cheap "cheater" chip used from day 1 on the SNES. The SNES CPU would suck at handling the 3D math, but it might do OK with the DSP helping with the math and the CPU just handling the rendering. That, and rendering to a mode 7 screen rather than horribly painful tiles. (bitplanes suck)
Using SA1 might be interesting too. (10 MHz 65816)

Again, a different topic though. (not that the SNES's main CPU couldn't/shouldn't have been faster from day 1 . . . we can only speculate why it wasn't)

Actually, if yo watched the EMUreview,
https://www.youtube.com/watch?v=AmHsQfXwppE
He says that the maker of the FX chip made a very primitive 3D demo game using the only the snes hardware and showed it to nintendo. Nintendo asked if he could do better and he said that it couldn't get better using such limited hardware.

Argonaut provided a basic demo for Starglider on the SNES, but suggested custom hardware to go beyond that. The programmers of that demo were not behind the Super FX chip, though. Argonaut Software comissioned Ben Cheese to design the Super FX (MARIO-1). He's notable for designing the DSP in the Flare 1 and related Slipstream chipsets (among other things, planned for use in the Konnix Multisystem), and Argonaut knew of him from the Konix project. (on another note, the other 2 designers of the Slipsteam -Martin Brennan and John Mathieson- went on to design the Atari Jaguar -Brennan first joined Atari in 1989 to complete the Panther GPU, but convinced Atari to take on the Flare 2 "Jaguar" project)

Not to mention, to make a 32X game, you have to be good at programming everything in software for two SH2 CPUs AND be able to work with a tiny amount of RAM. Stef is already really good at programming for Genesis, so that is the easier platform to work with.

It's not much RAM compared to the Sega CD or any 5th gen console, but it's still a lot more than the MD. You've got just 64kB of work RAM in the MD, and for a game like this, you've also got to renter into that RAM before copying to VRAM. (to cut down on that, you could render smaller strips of tiles at a time and DMA that to VRAM as needed, but even that would be limited)

32x gives you 256 kB of work RAM for the SH2s and dual 128kB framebuffers to render into . . . you could code the thing a lot sloppier on the 32x and still blow any Super FX (or SFX2) game away easily. (well, aside from some 2D SNES PPU specific stuff)

That's not the point here though, the point is showing how far the MD hardware can be pushed for this sort of game. (something the Sega CD hasn't been pushed at either -Stellar Fire is a pretty basic showing of that, and no other game even tried a fully polygonal game on the CD)

[Barone]

no other game even tried a fully polygonal game on the CD

Starblade says "hi!".

[Robotwo]

I like how 3gens "solution" to this discussion was to start a "Gen vs SNES" thread on NESdev :P

And somehow he thinks its all fair that the NES is way less powerful than the MD because it's older,
yet he completely overlooks that the stock MD was released 2 years before the SNES.

[NeoVamp]

Oh no, the hostility and popularity comment was towards NeoVamp. I don't think he likes me very much.

Just because I questioned your 32X comment? you think people are hostile because they question you?
I always question people's motives when they sprout "omg use 32X" because its 2013 and using the 32X makes as much sense as just using the latest hardware.

I have no ill feelings towards you, and I feel my comments were only aimed at your "use 32X" message, if that upset you then I apologize.

That said, people do tend to be dicks on the Internet, and I guess I've grown a thicker skin because of that, and it probably reflects in the way I present myself.

[TrekkiesUnite118]

I like how 3gens "solution" to this discussion was to start a "Gen vs SNES" thread on NESdev :P

And somehow he thinks its all fair that the NES is way less powerful than the MD because it's older,
yet he completely overlooks that the stock MD was released 2 years before the SNES.

Yeah I found that kind of funny. And the NesDev thread has some fun nuggets in it too. For example there's this post:

The SNES is technically supperior in all areas, and the so called faster CPU of the Megadrive is a hoax made by Sega fans, because even if it is clocked faster it needs more cycles to do anything making it roughly the same computing power as the SNES' CPU.
This is not surprising as the SNES is more recent

While I know that this is an issue and does slow down the 68k, it seems to be making a mountain out of a molehill if you ask me. It seems SNES fans have started throwing this around as a sort of catch all to any argument about the CPU in the Genesis.

[Barone]

The SNES CPU is 30% slower than the Genesis one in most of the cases, to begin with.