F-Theta

Started by Ghegs, July 28, 2020, 11:29:42 am

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Ghegs

https://twitter.com/ls_create/status/1288137312623144960

Somebody's creating a top-down racing game for the Famicom with some really impressive effects. As well as some impressive 8-bit T&A.

The Twitter account has some additional videos of the game as well. Hopefully the project will proceed and we'll eventually get something playable out of it. Hell, I'd pay money for a physical release.

Thanks to cuilanA for bringing this to my attention.

P

That's darn impressive, both technically and aesthetically! I usually say the genre generally works better in 3D than 2D, but this looks like it could be very fun.


Just hoping that it won't be released on one of those destructive cartridges that fails to convert between 3.3 V and 5 V.

Ghegs

Quote from: P on July 28, 2020, 01:29:16 pmI usually say the genre generally works better in 3D than 2D

It tends to, yeah. Which is a big bummer to me personally, since racing is probably my favorite genre, but Famicom is my favorite console, and other than very few actually good racers on the system, there's just no bringing these two loves together. This could be at least something to bridge the gap.

I've occasionally toyed with the idea of making a Neo Drift Out -type of game, but that'd require learning some serious FC programming.

P

I've also been toying with ideas of a 2D racing game in the style of Neo Drift Out. It's not a beginner project for sure. Something single-screen, like Sprint 2 or Super Off-Road, would be easier to start out with, but I would really like some better car physics with drifting possibilities.
That would need two types of friction: one wheel-friction when the car runs in the direction of the steering, and one boat-like friction when the wheels looses their grip due to various conditions, and the steering has no effect.

MWK

I wonder if it's some kind of trick or the real "bitplane rotating" magic happening here, just like in Mode 7.
Nevertheless, awesome and impressing!

P

You mean like some kind of mode 7 hardware in the cartridge? Judging by the low resolution and small screen I think he is faking a pseudo-bitmap mode by redefining the pattern tables in CHR-RAM as needed, possibly with help of raster effects. The vertically split screen is also evidence of that, since there is no way to split the screen vertically and use hardware scrolling.

As long as the pseudo-bitmapped display is no larger than the pattern table, it should be possible to address every pixel on that display (colours are still limited though, thus "pseudo"). But there must also be enough time to update the whole bitmap display every frame, or maybe every second frame or something. The intro with the race queen and the goal sequence seems to pseudo-bitmap the whole screen, but they are also played at a low frame rate and plays a fixed film clip.

The cars and parts of the time and speed displays seems to be made of sprites. You can see that the "km/h" briefly disappears when a car is horizontally aligned to it due to the 8 sprites/scanline limit being reached.

Ghegs

July 31, 2020, 04:00:13 am #6 Last Edit: July 31, 2020, 04:23:42 am by Ghegs
Quote from: P on July 29, 2020, 04:39:03 amI've also been toying with ideas of a 2D racing game in the style of Neo Drift Out. It's not a beginner project for sure. Something single-screen, like Sprint 2 or Super Off-Road, would be easier to start out with, but I would really like some better car physics with drifting possibilities.

I wonder if the R.C. Pro-Am games could be used as a base for a rom-hack version of a Neo Drift Out-esque racer? The engine seems solid enough (it's by Rare, after all), so if it would be possible to make the maps longer point-to-point affairs and tweak the physics to be a bit more drifty, that'd be pretty close to what I'm envisioning. Of course removing the combat elements, oil slicks and such would also be needed...

Or maybe Eliminator Boat Duel, come to think of it?

P

I'm personally not good with ROM hacks, and thinks it's easier to code everything from scratch, but if I had disassembled code of those games I could maybe learn some tricks how they do various things.

MWK

So, P, maybe they used the same trick/method as in Bad Apple demo?

UglyJoe

Quote from: MWK on August 02, 2020, 02:05:59 pmSo, P, maybe they used the same trick/method as in Bad Apple demo?
That's what the effects reminded me of, as well.

P

Yeah, not that I know how Bad Apple works, but I would guess at least the intro uses some similar method to playback full screen animation. Bad Apple is black and white, so colour is not a problem there.

Ghegs

Okay, so I managed to get my hands on the game, and I've been playing it for a bit.

There are 8 courses, and you race through the first four of them in "Skill Level 1" gameplay mode, and the second four in "Skill Level 2" gameplay mode. The aim is finish three laps before the time runs out, and while there are AI cars on the course, the game doesn't track placement at all, they're just moving obstacles. The last gameplay mode is Practice Mode, and it allows you to choose any of the eight courses and race three laps on it without the time limits and AI cars. It also doubles as a time attack mode, but the best times aren't saved, the cartridge doesn't have a battery.

The AI cars are the real challenge. The courses can get very narrow and hitting the other vehicles brings yours to a stop. And the time limits aren't very forgiving, so even just a few mistakes can spell doom to your race. There's no continues either, if you time out it's Game Over and you have to start the whole four-race set from the beginning. But the whole thing takes like 10 minutes, so it doesn't take long before you're back for another go at it.

The game's mechanics are simple. It's just A to accelerate and B to brake, there's no gear shifting (even just between low/high like in F1 Race) or anything else that I can discern. There are no car settings to tweak either. It's really the game's visuals that make it stand out, and though the graphics look simple at a glance, the game does things that I'm not sure if any game released during the system's original lifespan does. The framerate is on the lower end, but it's still perfectly playable. The music is of high quality as well, very good tunes.

The cutscenes, that happen after every race (though not in practice mode), with the race queen further show off the technical prowess and they also work as a reward for the player. I'm not sure if dev has shown all the cutscenes in his Twitter account, but some of them do get very...bouncy. The game has more T&A than the rest of the console's library combined, probably more than all 8-bit systems' libraries combined. And I'm sure there's a final cutscene after beating the fourth race - maybe Skill Level 2 even has a unique one? I'll do my best to finish them both so I can record the footage. So far I haven't even managed to beat Skill Level 1, my best was getting to the last lap of the last course and timing out while just coming out of the last corner.

It's a fun game with simple mechanics, but the audiovisual elements certainly make it punch above its weight.

P

I was almost expecting a very short demo, but it sounds like it's a neat little game, simple gameplay-wise but technically and artistically impressive. Hope I can get to play it someday.

So framerate is slow, I guess it's using 2 or more frames to update the screen during the game as well. The blocky graphics also makes me think it uses entire single-colored BG tiles as large meta pixels, or maybe a meta pixel system with 4x4-pixel blocks or something.

I don't think any commercial games used these type of techniques much at all, but that's mostly because the Famicom have smooth hardware scrolling and good sprite hardware. Some other computers and consoles that lacks sprites and/or scroll had to use this type of technique to animate the screen at all, but still they seldom scroll as smoothly as F-Theta does as they often just move the entire BG tiles one square each scroll step.

Compare MSX and Famicom versions of Zanac, PC-88 and MSX versions of Xanadu vs Faxanadu, MSX and Famicom versions of Romancia and Drasle Family among many other examples. These games on systems without hardware scroll (MSX2 lacks vertical hardware scroll) have a small screen with large surrounding status bar areas to make the part of the screen that needs to be updated every frame smaller. The Famicom on the other hand is limited to one status bar (or more with some mappers or a special trick) either above or below the screen as it needs to split the screen update horizontally to avoid the status bar from also scrolling with the rest of the screen.

Ghegs

I managed to beat Skill Level 1, after an extended play session and having to start from scratch a few times. Beat it just by a hair, I literally had one second left on the clock. Though the game does that thing where, after the time runs out, you car still rolls forward for a while, allowing you to just edge over the finish line. That's always cool.

There indeed is a final cutscene after finishing the last race, and it has the expected amount of cheesecake in it. Full video of Skill Level 1 here! Sorry for the age-restriction, but apparently Youtube is strict about this sort of thing nowadays, and I don't want to risk getting my channel banned, even though I don't actually monetize it. Just don't wanna risk losing all the vids I've uploaded over the last decade and a half because Youtube takes offense to pixel boobs.

I also discovered this tweet from the developer. Two of the pics relate to F-Theta, and one to his other game. Since I don't know any Japanese, I had to use Google Translate on my phone. Based on that horribly mangled translation, so take this with a huge grain of salt, there's a way to preview one of the animations, and there's a way to increase the time on the clock by 5 seconds. Maybe one of our Japanese-fluent members can shed some more light on this?

And now to start working on Skill Level 2...

P

QuoteThough the game does that thing where, after the time runs out, you car still rolls forward for a while, allowing you to just edge over the finish line. That's always cool.
That's a neat touch. I like this thing in this type of game. :)


Nice find on Twitter! I'll give it a quick translation:

He first says what type of board he uses (I guess it's the same for both his games):
Mapper 2 (either UNROM or UOROM), 256 kB PRG-ROM, CHR-RAM (as is expected with this type of graphic effects), vertical mirroring. He says that the silkscreen mirroring indication on the board shows the reverse mirroring from the one used (so it says H instead of V). But that's no different from official cartridge boards by Nintendo (it's actually the homebrew/emulator scene that got the mirroring thing backwards for some reason, so "vertical mirroring" is what Nintendo calls "H-scroll").

He then goes on saying that kazzo is able to both read and write to the ROM, so if you are using kazzo to dump the cartridge, be careful not to overwrite it. I guess the cartridge is using flash-ROM (which is a rewritable type of ROM). This also means the game has the means for saving data in an unused spot of the flash, but I guess it doesn't.

So it doesn't sounds like he minds if people dumps the ROM. Hopefully the ROM will show up some time. He also said that he will keep producing the cartridges until 2022 though.

He says you can also reprogram it with a ROM you made yourself if you like, using like a flashcartridge (but you are limited to 256 kB UNROM games of course) but you will have to resolder the mirroring jumper if you need to change the mirroring (or solder a slide switch so it can be changed back more easily).


Now to the secrets. It's those pictures in his tweet and two for F-theta and the other is for the other game he made "Utakata Synopsis;".

For the first F-Theta secret it says that before the Stage 4 demo starts you should hold a certain button pressed and you will see something you are not supposed to see (!). This also works with the last demo at the ending.
The first screenshot shows when you should start holding the button. But it says that you have to discover which button yourself. On the second picture, the red text says something like "Just what what kind of changes will happen when you do this? You got to find out!" ...intriguing!

Now to the second F-Theta secret. It simply says that you can gain 5 seconds by pausing the game and entering a certain command. The number of times you can use this trick depends on how many tracks you have completed, so it might not really be a cheat. I'm not sure if it's the number of times per game or the number of times per track.
It says you have to figure out the command yourself again.

I guess you could try the Konami command (AKA the Konami code)?