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Eh. Apologies about the NT post below. Had a slight browser mishap. In any event, congrats Vic_Viper, that rules. Not of much use to emulator programmers, but makes our understanding of SMS hardware that much more complete, and paves the way for homebrew SMS 3D games.

While on the topic of 3D glasses, Zoop said in the other forum that Maze Hunter 3D ROM wasn't released because no emulators supported it yet. Is there I way myself or other emu programmers could get a hold of it so we can work on that? Also, I've been wondering about "supporting" 3D games. I wonder if it'd be enough to just toggle red/blue frames (assuming you never frameskip), or if it's necessary to try to combine the frames into one (effectively halving the FPS) with red and blue components. Either way it's not an ideal solution but better than nothing.

Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. Anyhow, it only seems to be used on the Sonic games for the water effect. In general the h-int handling in CHASMS seems close to accurate, the only usual bugs are for instance in Outrun GG where the horizon scrolling goes one line too far down; many other emulators also do this. The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up.

- vecna

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> Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design.

SMS Plus (w/ 16-bit color), Master Gear (DOS), and Meka support palette effects.

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> It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette.

You're right, the colors do suffer a bit, but this can be
implemented much faster than native 16-bit rendering.

Hey, Magic Engine (DOS) looked great, despite the palette tricks. ;)

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> Anyhow, it only seems to be used on the Sonic games for the water effect.

Space Harrier (SMS/GG), Gangster Town, Golden Axe Warrior (only in the overscan area), Gunstar Heroes (GG), etc. also use it.

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> The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up.

CPU emulators won't really run for (say) 227 cycles when you run them, it can be a bit more or less. I haven't seen any SMS emulators that take that into account and execute more or less cycles on the following lines.

This is just an assumption, but I have two ideas here; I know the Genesis VDP will 'read' certain registers at one part in a scanline, and will ignore updates until the next line. Could be similar for the SMS. Also, maybe the scroll value is only noticed at the end of the scanline, but before the next one, which is the same time period when the V counter and all those other end-of-line events occur.
Both concepts would explain the 'one line off' scrolling problems I've seen in some emulators. But none of it applies to Sonic which is either a timing thing or has some weird use of line interrupts nobody knows about yet.

My Homepage

Quote

> Eh. Apologies about the NT post below. Had a slight browser mishap. In any event, congrats Vic_Viper, that rules.
>Not of much use to emulator programmers,

Actually I made that schematics and reverse engineering, because I'm developing an adaptor for connecting the 3D glasses in the PC LPT port.
Then I think it's interesting to publish my findings so other people may be able to use the information too ...

And I say, it's usefull for emu programmers, because if the emulator knows which cicle of the 3D display is currently on the screen
it's able to don't lose sync in the 3D effect.

Quote

> but makes our understanding of SMS hardware that much more complete, and paves the way for homebrew SMS 3D games.

That's the idea .. =).

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> While on the topic of 3D glasses, Zoop said in the other forum that Maze Hunter 3D ROM wasn't released because no emulators supported it yet.
> Is there I way myself or other emu programmers could get a hold of it so we can work on that?
>Also, I've been wondering about "supporting" 3D games. I wonder if it'd be enough to just toggle red/blue frames
> (assuming you never frameskip), or if it's necessary to try to combine the frames into one (effectively halving the FPS) with red and blue components.
> Either way it's not an ideal solution but better than nothing.

In the SMS there isn't RED/BLUE frames. There is LEFT and RIGHT frames. That's why the SEGA-3D glasses roxx so much !
No red/blue lenses !!! That's COOL ! =)

Quote

> Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. Anyhow, it only seems to be used on the Sonic games for the water effect. In general the h-int handling in CHASMS seems close to accurate, the only usual bugs are for instance in Outrun GG where the horizon scrolling goes one line too far down; many other emulators also do this. The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up.

> - vecna

Quote

> Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette.

Meka does (I would believe 'properly'), as does BRSMS with the -palraster switch (which also turns on support for changing vscroll values each frame, which is actually not supported in a real sms (or gg or genesis in MG mode)... i found that out the hard way, thanks again Mike G.). Meka also supports proper emulation of changes to the sprite table in hblank, I think brsms does too butI don't recall offhand.

Quote

>Anyhow, it only seems to be used on the Sonic games for the water effect.

also Space Harrier, and the title screen of tetracycline (which none of you have seen, ahahahhahahhhh!).

Quote

>> Anyhow, it only seems to be used on the Sonic games for the water effect.
> Space Harrier (SMS/GG), Gangster Town, Golden Axe Warrior (only in the overscan area), Gunstar Heroes (GG), etc. also use it.

From memory..

Power Strike 2 (GG)
Space Harrier (SMS/GG) & Space Harrier 3D
Gangster Town
Golden Axe Warrior
Gunstar Heroes
Sonic & Tails 2
Sonic
California Games
Championships Hockey
Poseidon Wars 3d

And probably many others.

As for giving away the ROM, I'll point it out that other 3D Roms are already out (Space Harrier 3d, Zaxxon 3d, Blade Eagle 3d, Poseidon Wars 3d, and Line of Fire) and it should be MORE that enough. If you really need it, feel free to e-mail me, though.

Quote

> And I say, it's usefull for emu programmers, because if the emulator knows which cicle of the 3D display is currently on the screen it's able to don't lose sync in the 3D effect.

Well, you'd only lose sync if you were frameskipping, and if you're frameskipping the 3d games are gonna look like crap anyway.

Quote

> In the SMS there isn't RED/BLUE frames. There is LEFT and RIGHT frames. That's why the SEGA-3D glasses roxx so much !
> No red/blue lenses !!! That's COOL ! =)

Well, I know that. But the shutter-style lenses for PC (for an emulator use) are very expensive. While it might be nice to have an emulator that supports them (I don't have a pair, unfortunately), for the rest of us, red/blue is probably the best emulation compromise.

But yeah, I agree. The fact that the SEGA had such "high-quality" 3d glasses that early in the game is exactly the kind of reason that SEGA kicks ass. :D

- vecna

Author	Message
vecna Guest	Palette raster effects, 3D glasses, etc. Posted: Thu Aug 31, 2000 6:13 pm
vecna Guest	Eh. Apologies about the NT post below. Had a slight browser mishap. In any event, congrats Vic_Viper, that rules. Not of much use to emulator programmers, but makes our understanding of SMS hardware that much more complete, and paves the way for homebrew SMS 3D games. While on the topic of 3D glasses, Zoop said in the other forum that Maze Hunter 3D ROM wasn't released because no emulators supported it yet. Is there I way myself or other emu programmers could get a hold of it so we can work on that? Also, I've been wondering about "supporting" 3D games. I wonder if it'd be enough to just toggle red/blue frames (assuming you never frameskip), or if it's necessary to try to combine the frames into one (effectively halving the FPS) with red and blue components. Either way it's not an ideal solution but better than nothing. Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. Anyhow, it only seems to be used on the Sonic games for the water effect. In general the h-int handling in CHASMS seems close to accurate, the only usual bugs are for instance in Outrun GG where the horizon scrolling goes one line too far down; many other emulators also do this. The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up. - vecna

Charles MacDonald Joined: 28 Sep 1999 Posts: 1197	Posted: Thu Aug 31, 2000 9:27 pm
Charles MacDonald Joined: 28 Sep 1999 Posts: 1197	Quote > Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. SMS Plus (w/ 16-bit color), Master Gear (DOS), and Meka support palette effects. Quote > It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. You're right, the colors do suffer a bit, but this can be implemented much faster than native 16-bit rendering. Hey, Magic Engine (DOS) looked great, despite the palette tricks. ;) Quote > Anyhow, it only seems to be used on the Sonic games for the water effect. Space Harrier (SMS/GG), Gangster Town, Golden Axe Warrior (only in the overscan area), Gunstar Heroes (GG), etc. also use it. Quote > The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up. CPU emulators won't really run for (say) 227 cycles when you run them, it can be a bit more or less. I haven't seen any SMS emulators that take that into account and execute more or less cycles on the following lines. This is just an assumption, but I have two ideas here; I know the Genesis VDP will 'read' certain registers at one part in a scanline, and will ignore updates until the next line. Could be similar for the SMS. Also, maybe the scroll value is only noticed at the end of the scanline, but before the next one, which is the same time period when the V counter and all those other end-of-line events occur. Both concepts would explain the 'one line off' scrolling problems I've seen in some emulators. But none of it applies to Sonic which is either a timing thing or has some weird use of line interrupts nobody knows about yet. My Homepage

Vic_Viper Joined: 12 Jul 2005 Posts: 55	Posted: Fri Sep 01, 2000 4:40 am
Vic_Viper Joined: 12 Jul 2005 Posts: 55	Quote > Eh. Apologies about the NT post below. Had a slight browser mishap. In any event, congrats Vic_Viper, that rules. >Not of much use to emulator programmers, Actually I made that schematics and reverse engineering, because I'm developing an adaptor for connecting the 3D glasses in the PC LPT port. Then I think it's interesting to publish my findings so other people may be able to use the information too ... And I say, it's usefull for emu programmers, because if the emulator knows which cicle of the 3D display is currently on the screen it's able to don't lose sync in the 3D effect. Quote > but makes our understanding of SMS hardware that much more complete, and paves the way for homebrew SMS 3D games. That's the idea .. =). Quote > While on the topic of 3D glasses, Zoop said in the other forum that Maze Hunter 3D ROM wasn't released because no emulators supported it yet. > Is there I way myself or other emu programmers could get a hold of it so we can work on that? >Also, I've been wondering about "supporting" 3D games. I wonder if it'd be enough to just toggle red/blue frames > (assuming you never frameskip), or if it's necessary to try to combine the frames into one (effectively halving the FPS) with red and blue components. > Either way it's not an ideal solution but better than nothing. In the SMS there isn't RED/BLUE frames. There is LEFT and RIGHT frames. That's why the SEGA-3D glasses roxx so much ! No red/blue lenses !!! That's COOL ! =) Quote > Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. Anyhow, it only seems to be used on the Sonic games for the water effect. In general the h-int handling in CHASMS seems close to accurate, the only usual bugs are for instance in Outrun GG where the horizon scrolling goes one line too far down; many other emulators also do this. The h-ints on Sonic during the water stages show somewhat more severe bugs, however. I'm just wondering if anyone else has looked at this and gotten it to work correctly. There seems to be some things about the h-int handling that we still don't fully understand, but it's entirely possible my code is just messed up. > - vecna

Heliophobe Site Admin Joined: 25 Oct 1999 Posts: 2029 Location: Monterey, California	Posted: Fri Sep 01, 2000 5:07 am
	Quote > Also, it's come to my attention lately that CHASMS seems to be the only emulator so far to properly handle h-int palette changing (let me know if I'm wrong!), due to the high-color native nonpaletted design. It's possible to hack the palette effects in 8-bit color, but it's generally nasty and can't be done for Game Gear games well due to the 512 color palette. Meka does (I would believe 'properly'), as does BRSMS with the -palraster switch (which also turns on support for changing vscroll values each frame, which is actually not supported in a real sms (or gg or genesis in MG mode)... i found that out the hard way, thanks again Mike G.). Meka also supports proper emulation of changes to the sprite table in hblank, I think brsms does too butI don't recall offhand. Quote >Anyhow, it only seems to be used on the Sonic games for the water effect. also Space Harrier, and the title screen of tetracycline (which none of you have seen, ahahahhahahhhh!).

Zoop Joined: 24 Jun 1999 Posts: 1732 Location: Paris, France	A list ? Posted: Fri Sep 01, 2000 6:49 am
	Quote >> Anyhow, it only seems to be used on the Sonic games for the water effect. > Space Harrier (SMS/GG), Gangster Town, Golden Axe Warrior (only in the overscan area), Gunstar Heroes (GG), etc. also use it. From memory.. Power Strike 2 (GG) Space Harrier (SMS/GG) & Space Harrier 3D Gangster Town Golden Axe Warrior Gunstar Heroes Sonic & Tails 2 Sonic California Games Championships Hockey Poseidon Wars 3d And probably many others. As for giving away the ROM, I'll point it out that other 3D Roms are already out (Space Harrier 3d, Zaxxon 3d, Blade Eagle 3d, Poseidon Wars 3d, and Line of Fire) and it should be MORE that enough. If you really need it, feel free to e-mail me, though.

vecna Guest	Posted: Sat Sep 02, 2000 12:06 am
vecna Guest	Quote > And I say, it's usefull for emu programmers, because if the emulator knows which cicle of the 3D display is currently on the screen it's able to don't lose sync in the 3D effect. Well, you'd only lose sync if you were frameskipping, and if you're frameskipping the 3d games are gonna look like crap anyway. Quote > In the SMS there isn't RED/BLUE frames. There is LEFT and RIGHT frames. That's why the SEGA-3D glasses roxx so much ! > No red/blue lenses !!! That's COOL ! =) Well, I know that. But the shutter-style lenses for PC (for an emulator use) are very expensive. While it might be nice to have an emulator that supports them (I don't have a pair, unfortunately), for the rest of us, red/blue is probably the best emulation compromise. But yeah, I agree. The fact that the SEGA had such "high-quality" 3d glasses that early in the game is exactly the kind of reason that SEGA kicks ass. :D - vecna

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