Could Dreamcast et al handle this/that game/effect? *DC tech retrospective *spawn
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Cloofoofoo
Regular
Looks awesome. Has everything intact. Lighting , environment maps , motion blur( trails) . Even more peds and vehicles seem to spawn than other console versions. Textures seem upgraded no longer 32x32. Nice. Even a few extra yet cpu heavy stuff like more fences( as stupid as that sounds the other console version is missing quite a few and seem to had vu assembly to deal with it ) that uses sh4 assembley.
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Interview
Grand Theft Auto 3 for the Dreamcast - DCA3 Alpha Version Now Available
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Cloofoofoo
Regular
They already did a PS2 comparison. With motion blur on seems to be around 8:30 mark. Interesting differences. DC version inherited the colors of the pc version with a slight shorter draw distance than PS2. The effects also look like the pc version as opposed to PS2( the rain).
Edit: the video also highlights a big bug on the dc. When you set brightness super high it breaks the stages vertex colors. So it looks like it has none. It does and does provided you don't max the brightness.
Edit: the video also highlights a big bug on the dc. When you set brightness super high it breaks the stages vertex colors. So it looks like it has none. It does and does provided you don't max the brightness.
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What version did the textures come from because that seems small even for 2001
Cloofoofoo
Regular
Textures are converted from the pc version ( which if I remember right where something like 128x128) . Early days of the porting for vram reasons it was reduced to 32,32. Now it's the new vq converter that does better quality textures I believe by default everything ( textures) will be converted to he half the size by default ( so if 128x128 now 64x64) . 32x32 does seem low but believe it or not the PS2 version uses a lot of textures that size with low colors depths ( 4 bit colors). So it's not as bad as one would think. The improved textures is probably why it seems less muddled and overly sharp now( when blur is off). The models are intact from the PC version which some are higher than the PS2 version.
Cloofoofoo
Regular
Motion blur side to side with motion blur off. Performance hit isn't as bad as one would think for a post process effect on DC :
Seems like there's more active elements, so cars and pedestrians, but framerate does take a knock at numerous points. What's the 'motion blur' - drunk mode?
PS2 didn't look like that. A naive blend of previous frames doesn't seem quite right.Still, shows GTA could definitely be done on DC! Nice to have an answer to this question for once, and it upends a lot of assumptions/expectations about the hardware differences. Theories that DC couldn't do XYZ are disproven, and that brings in question other ideas about ports.
Cloofoofoo
Regular
Seems like there's more active elements, so cars and pedestrians, but framerate does take a knock at numerous points. What's the 'motion blur' - drunk mode?
Still, shows GTA could definitely be done on DC! Nice to have an answer to this question for once, and it upends a lot of assumptions/expectations about the hardware differences. Theories that DC couldn't do XYZ are disproven, and that brings in question other ideas about ports.
Motion blur is done pretty much like the PS2 version , using the front buffer as texture. This unfortunately isn't as easy to do in the DC because the framebuffer in the DC isn't usable a texture directly unlike other consoles so workarounds has to be done to make it possible. I think though why you think it looks like drunk filter because how wildly the framerate swings which affects how the blur appears, 15 to 30 fps during busy scenes.
Well they feel there's room for performance improvements. I know skmp has mentioned that they can get much closer to 30 fps with more time and work. There's also a lot of cool tricks that weren't used in its lifetime. For the fast tnl they are doing is making meshlets out of the models and using half of the CPU cache to store up to 128 vertices as fast scratchpad / general memory! To perform tnl quickly. Skmp has mentioned though it's meant to store 128 vertices the actual average usage is around 63 vertices and could render double of what they are doing( some overhead in other areas might need sorting first). While physics have been more optimized with sh4 asm ( apparently because of fences physics tanking frame rate unexpectedly, which seems to be the reason alot of fences are missing on the PS2 version) there's more stuff that hasn't been optimized to that level yet. I know they were working on something they call hybrid rendering that unfortunately didn't make it into this port, basically the dc buffers the verts for the scene twice taking a lot of memory, hybrid rendering allows direct submissionto the vram/gpu of the biggest polygon type ( usually opaque ) and leaves the others buffered. That should free up memory and keep performance same or even faster performance under certain conditions due to just blasting verts to the GPU as quick as they can. Imagine all this and this is not even mentioning the gpu quirkiness.
I think they said it best, that while it's easy to get something mediocre on screen for dc getting it to hit it's stride is as hard as PS2 due to needing completely custom code to leverage sh4 asm , sq , ocram mode( or even harder because it's performance ceiling is lower and fragile since one wrong line of code can completely make your frame rate tank). Which is not bad for a group of 5 people with no funding working on reversed engineered code. I guess the lack of market support sealed it's fate since it needed that kind of popularity for the developers to put the same kind of work they did on PS2 and vus asm.
Is this running off optical?
EsppiraK
Newcomer
It can be run from a CD but there needs to be file sorting and other optimizations that hasn't been implemented yet for it to run properly, right know the biggest issue is the SFX of pedestrians, they have some ideas on how to pack and sort the files on the cd to fix it but that is reserved for the next release, this is a video of an older build running from a CD which by the way has slower read times than an official GD-rom so no a 1/1
You can see how the game stutters when it has to load SFX, I think they added a quick not final workaround for the alpha release but I haven't tested it.
It can be run from a CD but there needs to be file sorting and other optimizations that hasn't been implemented yet for it to run properly, right know the biggest issue is the SFX of pedestrians, they have some ideas on how to pack and sort the files on the cd to fix it but that is reserved for the next release, this is a video of an older build running from a CD which by the way has slower read times than an official GD-rom so no a 1/1
Are you aware of anyone ever managing to burn GD-Roms, perhaps using modded firmware for a burner and specific CD-Roms? The true media for the device being locked away and the substitute being half the read speed being half the read speed (or less) with worse access times is one of the big bummers about game development and preservation for the DC. I hope my disks aren't rotting away like some CDs and DVDs have ...
Cloofoofoo
Regular
It can but it's not optimized for it atm( wasn't a priority for alpha release ) . Some work is needed on audio and disc drive related code. Pedestrian and other sfx cause a stutter not so much the radio music. Remember cd from like gdrom has a handicap of seek time but made worse by the fact it runs around 600 kb/s versus from 1mb /s
Cloofoofoo
Regular
Wow thats
Wow that's actually not half bad. I guess if they downsample enough and fix drive and sound code should be fine on the drive even if it's only half as fast as retail games.
It can be run from a CD but there needs to be file sorting and other optimizations that hasn't been implemented yet for it to run properly, right know the biggest issue is the SFX of pedestrians, they have some ideas on how to pack and sort the files on the cd to fix it but that is reserved for the next release, this is a video of an older build running from a CD which by the way has slower read times than an official GD-rom so no a 1/1
You can see how the game stutters when it has to load SFX, I think they added a quick not final workaround for the alpha release but I haven't tested it.
Wow that's actually not half bad. I guess if they downsample enough and fix drive and sound code should be fine on the drive even if it's only half as fast as retail games.
That looks better than I expected. Probably even an improvement over the PS2 version
davis.anthony
Veteran
Not taking anything away from the guys working on the port and looking at it purely from a visual comparison point of view, It still has to improve massively in some key area's to compete with the PS2 version:
- Draw distance is noticeably reduced and very poor in places (7:22 & 11:01 in the video show how much better draw distance is on PS2)
- LOD transitions are abysmal and happen extremely close to the player (11:42 & 12:43 in the video shows this off well, although it's visible all over the video)
- Performance visually lower than the PS2 version (developers have already confirmed the frame rate, which is lower than the PS2 version)
- Reduced texture resolution, which can be massive in some cases (noticeable throughout the whole video but 13:49 especially shows how much better textures are on PS2)
Now the game is noticeable sharper on Dreamcast but it's no doubt contributing to the low performance and ideally could do with the resolution dropping to help the frame rate.
So far this port is proving two things:
1. Dreamcast can, as some have suggested, handle a 3D GTA game.
and secondly....
2. Dreamcast cannot handle the PS2 version of GTA3.
- Draw distance is noticeably reduced and very poor in places (7:22 & 11:01 in the video show how much better draw distance is on PS2)
- LOD transitions are abysmal and happen extremely close to the player (11:42 & 12:43 in the video shows this off well, although it's visible all over the video)
- Performance visually lower than the PS2 version (developers have already confirmed the frame rate, which is lower than the PS2 version)
- Reduced texture resolution, which can be massive in some cases (noticeable throughout the whole video but 13:49 especially shows how much better textures are on PS2)
Now the game is noticeable sharper on Dreamcast but it's no doubt contributing to the low performance and ideally could do with the resolution dropping to help the frame rate.
So far this port is proving two things:
1. Dreamcast can, as some have suggested, handle a 3D GTA game.
and secondly....
2. Dreamcast cannot handle the PS2 version of GTA3.
How do your observations relate to the PC version on PC? Were they limitations of that version, or could that version scale to (and beyond) PS2?
davis.anthony
Veteran
Coincidentally the same channel I used for the DC vs PS2 video also did a PS2 vs PC video around 8 months ago.
- Draw distance noticeably better on PC
- LOD transitions noticeably better on PC
- Texture resolution better on PC (Although not on ever texture and the increased rendering resolution is likely also helping)
That's a bit of a one sided take IMO.
Textures are lower in some places and higher in others with the current build, which doesn't yet have all the texture conversion and streaming optimisation in place (probably little to no streaming optimisation really).
In some ways they're limited by the scalability settings of the PC version, which appears to be making them use higher than PS2 setting in some areas e.g. geometry, object and traffic density, physics calculations on additional obstacles like fences not present in the PS2 version. If they could cut back down to the lower complexity that the PS2 version used (which would need a lot of work from an modeller / artist) they would free up both memory and CPU time. Enough to match the PS2 in all areas? I dunno.
Also, with KallistiOS iirc access to the optical drive is slower than for commercial games, using a lot more CPU and not using all the hardware features available to commercial games. Something to do with optical drive DMA...?
With motion blur on, fillrate will be an issue for the DC, but without it, it's probably only during certain situation like with heavy rain settings for cinematics like with the intro.
DC can't actually drop to a lower resolution like the one PS2 used for GTA3. It's 640 x 480 - Sega made the decision to base the design around high IQ and built the binning and tiling stuff into hardware for performance reasons. It took a ton of work off the CPU and meant they could rapidly sort and ID lots of polygons - faster than the later PC version of PVR2, with a fraction of the CPU overhead.
Internally the DC is always 640 x 480 24+8bit, it's one of the reasons its ouput always so good, and with the hardware flicker filter it's also why interlaced output was always so good.
I mean, it's currently handling above the PS2 in several areas. 640 x 480 RGB progressive scan is a pretty huge step up, and the object density, geometry, and collision upgrades definitely won't be free.
But at this level, are these really "versions" in any meaningful way? It's the same game. It plays the same, uses the same rules, looks and runs worse in some ways, looks and runs better in others (e.g resolution x frame rate).
It's already close enough for the argument to be well and truly over IMO. I'd say the same for a PS2 version of Shenmue that had slightly worse texture quality but a more stable frame rate, or for a PS5 game that had a slightly lower max dynamic resolution than the SXS version.
davis.anthony
Veteran
unprofessional conduct, this breaks our community rules. Do not respond to this.
I'm just stating what I see.
I've not seen any, do you have any time stamps?
The draw distance etc is well below what PC uses above PS2.
Any time stamps for this stuff?
Which I can't see in the video....
It's no where near close enough imo.
It's not the same as GTA3 though, as you would be porting to a more powerful platform and not porting to a lower performing one, and given the hardware differences, PS2 should be able to offer major graphical upgrades over DC in a theoretical Shenmue port.
Poor comparison, if the gap between PS5 and XSX equaled the DC and PS2 gap, you would be looking at much more then a difference in dynamic resolution.
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