Could Dreamcast et al handle this/that game/effect? *DC tech retrospective *spawn
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Cloofoofoo
Regular
Not 100% what's he is doing but that's not how it works. Basically it's all procedural , made algorithms for making the meshes dynamically , keep allocation in check since he divided what's drawn on screen into chunks of blocks( basically hundreds). Not to mention his work on getting vertices fast as possible cycle wise on the CPU is something that is general purpose.
And youre misunderstanding how the drawing stuff on screen for dc WILL take vram. It's that simple , this guy is drawing 100,000 vertices ( and probably over at this point) each 32 byte, your looking at over 3 mb vertex buffer. It's no free lunch.
And it's Minecraft... He's basically working on world generation / user created , it's a real game scenario. It's a pretty big feat pushing what he is pushing for his Minecraft clone game.
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It sort of already runs better than GTA4 on PS3 xD
Definitely hitting those milestones! Once the clipping is figured out, I'd dare say it's playable!
davis.anthony
Veteran
Possible in a tech demo yes, as the video proves.
But possible in an actual game? That's a different kettle of fish.
But possible in an actual game? That's a different kettle of fish.
I'm sure it could be used in some pretty impressive scenarios!
davis.anthony
Veteran
It would depend on the game really, a world like Shenmue? I'm not so sure.
But something like Power Stone 2? Maybe...
It's possible I'm reading the documentation wrong, but it looks like the GS cannot do colored specular as easily as the PVR.
A vertex on the PVR has two colors, a multiplicative color for diffuse lighting and an (optional) additive color, for specular. There's no fillrate cost for enabling the additive color, but, when it's enabled, it does take up more RAM in the scene buffer to store the extra color data, and some extra bandwidth to write and read it. (Maybe there is some setup cost too, but I'm not sure.)
The GS appears to only support a single, multiplicative vertex color. It has a mode that does something similar to the PVR's second color, which adds the alpha value to all color channels (a white specular). but if you want a PVR-like (TexColor * VertColorA + VertColorB), where VertColorB is not white, it looks like on GS you have to use a second pass with additive blending to do it.
The lighting in VF4 ties into gameplay (to indicate different types of hits), so desaturating the lighting isn't an option. You can't fake the specular lighting with the multiplicative lighting (red light on a blue outfit wouldn't show), so you have to do two passes. At that point, it's not a big extra cost to replace the vertex specular with an environment map, so that the highlights don't disappear between vertices.
The arcade textures seem like they would fit. I've only ripped the textures for the attract mode for Final Tuned.@TapamN , speaking of Naomi 2 to DC theoretical ports, what do you think of the ps2 assets being used for DC? I feel ike it would have the arcade textures with maybe two lights and for the water pool/snow arenas, it would be alittle more simplified. Maybe the snow wouldn't deform and be more like doa2, which i wouldn't complain about
Character texture size varies by a lot more than I would expect. Akira and Shun Di around 550KB after compression, but Pai and Lei-Fei are less than 300KB. The arena in VF4FT's attract mode is about 700KB after compressing everything. After adding HUD textures, you could probably fit everything in 2.5-3MB.
I think the PVR could handle the PS2's geometry, with vertex specular instead of environment map specular, but the bigger issue would be doing the lighting and skinning on the SH4. Some stages have render to texture effects, or spotlights on the arena, which might need to be cut.
You're right. I wasn't feeling well, so I didn't think through how to phrase it correctly. My mistake.
No numbers, but I would estimate most PS2 games reserve around four to eight MB of main RAM for textures.
Just because Rockstar had trouble getting the streaming to work on the PS2 does not mean GTA3 is beyond the DC. It's the first game of it's kind on a console, so it's not remotely close to using the full potential of the PS2.
While the sequential read speed does matter, usually the bigger problem with streaming from any spinning disc (CD, GD, DVD, or HDD) is the seek speed. Seek speed would depend on the physical construction of the disc drive, including things like the motor used and the weight of the laser assembly, so physics would put a limit how much of an advantage in seek speed the PS2 might have over the DC. I doubt the difference in seek speed is as big as the difference in ideal sequential reads.
And there's a lot of work to do with getting GTA's streaming to work besides bandwidth, like memory fragmentation or correctly building the map chunks, so "Rockstar had trouble with streaming" is too broad to assume that bandwidth was such a big problem that it's impossible to get working on the DC.
I think I remember hearing that there's a pirate version of GTA3 with most of the radio stations removed, so that it can run from a CD instead of a DVD. That's strong evidence that the PS2's top read speed for DVDs isn't required for GTA3.
The PVR supports seven texture pixel formats: RGB565, ARGB1555, ARGB4444, YUV422, normal map, 8BPP palettized, and 4BPP palettized. They all take two bytes per pixel, except for the palettized formats, which are 1 byte or 1/2 byte per pixel. All of these can also be VQ compressed, which reduces the texture size by 1/8th, plus codebook overhead.
Palettized textures were used, but I don't think any commercial game ever used VQ compressed palettized textures. I could have sworn I read on one of Simon's posts here that ImgTec only created a compressor for 4/8BPP VQ right as the DC was being canceled, and it was intended to be released in the final SDK version, but I'm not finding it. Maybe it was the dcdev Yahoo Group?
The PVR's VQ can't flip or mirror codebook entries, so any compression that does that would have to run on the CPU, either using the CPU to decompress to a texture, or drawing tilemaps with polygons. The KoF games used uncompressed 4BPP textures to store 16x16 character tiles, then used quads to build the characters.
Skies of Arcadia had bloom in a cutscene.
It's really not. You could easily create a DC game with bloom. The issue isn't "can the DC do it in a real game" but "are the gains from bloom worth the cost?" It costs fillrate, polygon count, and texture resolution/variety to do bloom, and it might be better to skip bloom and use those resources for something else. Sonic Adventure 2 at 30 FPS with bloom is totally doable, but 60 FPS without bloom is the better option.
davis.anthony
Veteran
The whole point of the discussion is could it handle the PS2 version of GTA3, everyone has acknowledged multiple times that it could handle an alternate version of GTA3 in some form or another.
So yes, if streaming was a big issue on PS2, it's likely to be an even larger problem on DC.
Well yes, GTA:VC and GTA:SA proved that.
We have actual Tweets from a developer highlighting how difficult the asset streaming was, and again, the discussion has been around the PS2 version.
Google shows up nothing for this so called stripped out GTA3 for PS2, and even then, side by side tests would need to be completed to see if there's truly no difference in asset streaming or loading.
So it's not evidence at all.
Yeah, theres definitely something weird about ps2 and the colored speculars. Easiest way to see it is when you pick zack's alien costume and taunt; the light actually reflects on his body on DC. There's nothing there on ps2.
As far as a theoretical vf4, the way pvr renders is the main reason i think it would look closer to arcade than what we got on ps2. Yes, i agree things like rtt and certain lights would probably be removed (just like ps2 lost a bunch) but i still think it would look damned good! I'm sure the spotlights could stay, they just probably wouldn't light the fighters the same way. Hopefully a tech demo could show it someday!
Hey, sonic Adventure 1 was 30fps, so 2 wouldn't be half bad at 30fps with bloom, but i get what you mean! Cutscenes at 30fps including bloom would be nice, too!
From my understanding with ian Michael, everything was on the CD version for ps2. Maybe he forgot to mention it. Either way, i bet it could all be compressed to a cd in mono if need be. Or somgs could be shortened, and most would barely notice. The coders over on DC said all the gamedata is only 200 megs, so that leaves alot of room for audio and those little videos.
I hope we get to see the full potential of DC someday soon!
wow where do I get a 32 meg ram mod done and what do I need to take advantage of it lol
It's working on 16megs now, so no need!
I keep forgetting how realistic thst scene in MakenX looks! I could never put my finger on why f355 didn't look as good. I just attributed it to texture res and screen res in general, lol. Did you see the cool effects in skies later on with that deathstar looking thing?
Cloofoofoo
Regular
Well both projects are huge undertakings , there isn't much to report so quickly.
On the GTA 3 side of it they tested gdrom drive with a burned copy and it runs fine no issues. The game itself full assets is only 200 to 300 MB on the disc and not to mention the layout hasnt been optimized so it doesn't look like it won't be any trouble what so ever. Another thing the save format from the PC version is extremely wasteful and saves data not even the PS2/Xbox version do leading to a huge 1 mb file that won't fit on vmu. They are gonna have to chop it down to size.
Graphics side they found the PC version files are console unfriendly to the max its a miracle it even runs like this. Seems they are going to make a dc native version model format that actually uses triangle strips( what DC prefers for max speed) because currently it does not. Textures are being converted pvr format . Lastly the biggest changes are gonna have to be optimization of the rendering, clipping and culling are being added which is a huge task. It's not a question if the DC can run the PC version of the game it's a question if 2/3 people can stick it out to do this huge amount of work and optimize graphics. It already runs on stock 16 MB Dreamcast and on cdr so two of the biggest hurdles are out of the way.
For the Minecraft clone I noticed he responded to some guys with some stats, he is pushing alot of vertices second as is (over 4.2 million a second @ 30 fps) and seems to want to optimize more to push even higher at a unflinching 30 fps. To match the GameCube version it seems ( he is working on both simultaneously).
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Absolutely. Especially when pps was mostly hovering in the 1-3 million pps the whole gen, lol