What IS Stunts anyway?

[Cas]

This thread, I'm starting it after exchanging a few messages with Duplode about Stunts when compared to realistic driving engines. We all know that Stunts is different, but I wonder which characteristics we recognise in Stunts as unique and which of those we really embrace. In contrast, it'd be interesting to mention which ones we wouldn't miss if they weren't there anymore (or maybe we've come to love them all). I'm talking mainly about the physics in the game.

I can quickly think of powergear and how easily it is for a car to be shot very high up into the sky with just the power of its engine. These things, personally, I find attractive and would certainly miss. On the other hand, I would not miss coming from a jump and landing exactly where two pieces of elevated road meet and crashing instantly. I am also unsure about being able to remain upside down inside a pipe or going throw slalom stones or loops, whether I'd miss those or not. What do you guys think?

[Daniel3D]

Well, I don't remember what the interview said about what bugs were and what features.
But in my head I always had my favourites.

I always considered powergear to be a bug and didn't like it much. I tried to avoid it.
Something like it should be in a remake though. (Maybe only as long as you are on track). Because it is a characteristic I recognise in Stunts as unique.

Driving through stuff like the slalom blocks or the loop is definitely a bug and I don't care for it.

Driving upside down I always regarded as a cool feature. But a bit more realistic would be awesome.

Fluke crashes because you land wrong are irritating. But a better relationship between speed, downforce and weight vs distance could be interesting.

I think I favour calculated physics above stimulated ones. @cas, you probably know what I mean.

[Duplode]

I think an important aspect of Stunts is how it handles grip, oversteer and understeer. It doesn't need to be super realistic (in fact, it's probably better if it isn't), but any Stunts-inspired physics engine should give you a clear sense of the grip limits and make it possible to get it wrong at a corner both by leaving the track "through the tangent" and by spinning, as well as to sometimes correct spins through countersteering. More generally, the handling feel of the cars (at least the non-cheat ones) should not be too arcade-like (in the "change direction however you want" sense) but also it shouldn't feel like you are always driving on an icy lake (a problem seen with some remakes and demos over the years).

For something unrealistic, I would nominate the possibility of changing direction in mid-air by taking jumps while sliding or spinning. In this case, I guess there is a fine line between fun and ludicrous for potential implementations.

A curious case is that of jump boosts, that is, the way accelerating through a jump can, depending on your choice of gear/RPM on takeoff, get you some extra speed upon landing. As important a part of the driving techniques repertory as it is, it is easy to forget that 1990 Stunts didn't have it at all! (And 1990 Stunts is no obscure version with limited distribution: Luke Loehrer created the Competition Car back in the day specifically for the benefit of its users, and it was the one I had back in the nineties.) I'm unsure about how essential jump boosts really are; good arguments can probably be drawn either way. There also is its partner-in-crime, the aerodynamic resistance bug which makes it possible for most cars (the Carrera is a rare exception) to stay above their flat track top speed without getting slowed down. Changing that would nerf jump boosts by making the very high speed ones temporary.

[Daniel3D]

I think an important aspect of Stunts is how it handles grip, oversteer and understeer. It doesn't need to be super realistic (in fact, it's probably better if it isn't), but any Stunts-inspired physics engine should give you a clear sense of the grip limits and make it possible to get it wrong at a corner both by leaving the track "through the tangent" and by spinning, as well as to sometimes correct spins through countersteering.

I completely agree.
Maybe combined with front, back or four wheel drive and the possibility to drift.

[CTG]

What is Stunts anyway?

A great retro racing game to be enjoyed, and not to be overanalyzed.

Little less reverse engineering, little more racing, please!

[Cas]

Oh, but there is a reason for this   We're not talking about reverse-engineering; we're talking about re-creating the engine

[Daniel3D]

Oh, but there is a reason for this   We're not talking about reverse-engineering; we're talking about re-creating the engine

We're not talking about reverse-engineering; we're talking about re-creating the engine

we're talking about re-creating the engine

re-creating the engine
re-creating the engine
re-creating the engine

[I've been longing for a good successor for over 20 years... No pressure CAS]

[Cas]

Yes, we've seen many successors that are actually very different from Stunts or were never finished or both... Now I'm not saying that in this case it's easy and that I can assure you I'll do better than them, no... But there is a difference. I'm not trying to create a sequel for Stunts. I'm only wanting to make an engine from scratch that can load the files from original Stunts and be playable, so that we finally have a source code we can work on and mod. It's a different approach from that of disassembling and also different from making a new game, yet it is still challenging.

[alanrotoi]

There are some bugs that can't be missed.
- The "turn in the air" trick.
- The "legal" shortcuts. The way we find to make shortcuts without penalty time (so there must be a shortcut penalty system and it must be fallible)
- Power Gear is THE classic trade mark of Stunts so can't be missed.
- and of course the Magic Carpet

In another order of things I would like to add:
- there  should be driveable on the decorative objects like buildings and Joe's bar
- a car builder, performance, chassis, size, etc.
- some kind of Jesus Power Gear just to drive on water.
- flying objects like zeppelins or balloons to have the possibility to use them to impulse the car speed, maintain/change a direction, make more jumps, etc. More aereal stunts.

things to miss:
- how easy is to get your car crashed or uncontrolled

A curious case is that of jump boosts, that is, the way accelerating through a jump can, depending on your choice of gear/RPM on takeoff, get you some extra speed upon landing. As important a part of the driving techniques repertory as it is, it is easy to forget that 1990 Stunts didn't have it at all! (And 1990 Stunts is no obscure version with limited distribution: Luke Loehrer created the Competition Car back in the day specifically for the benefit of its users, and it was the one I had back in the nineties.) I'm unsure about how essential jump boosts really are; good arguments can probably be drawn either way. There also is its partner-in-crime, the aerodynamic resistance bug which makes it possible for most cars (the Carrera is a rare exception) to stay above their flat track top speed without getting slowed down. Changing that would nerf jump boosts by making the very high speed ones temporary.

That's right! In Broderbund 1.0 version there aren't allowed jump boosts but it changed in BB 1.1. I knew them when I arrived at Zak's and started to use BB 1.1 version. This is detail or bug or something that can't be missed either.

[Cas]

Uhm.... this is a really interesting list. What I have so far for the engine is the pretty complete, but not fully, graphics engine, that is, the part that renders 3D shapes. I'm adding grills soon and spheres and line segments, which my older engine did not have. Wheels must be there too, but I'll leave that as the final item to add to the graphics engine because they're pretty complex. This part of the engine, the way I've devised it, will provide new features such as:
- The possibility to place objects not necessarily aligned with the grid, although they should be if they are active track elements or terrain elements, as they directly connect with adjacent ones
- All degrees of rotation on the Z axis (I'm using a Z = bottom-to-top coordinate system) for track elements. As before, only scenery should use this normally, but yes, you could place an object facing in any direction, not just multiples of PI/2
- Of course, the freedom to create new track and terrain elements, which would include cliffs and more stunts
- Multi-height maps, as my engine allows for placing stuff at any altitude

What I still have not started doing is making the actual physics engine, which is why I created this thread, to start having ideas on that. I intend to respect all of the physical attributes Stunts cars have, that is, the ones that work the way they're supposed to, like grip, torque, etc. For the ones that resulted from bugs, I don't think I can make them occur the same way, that is, reproduce them by creating the same bugs, but instead, I would have to force them to exist by "synthesizing" them. This should allow also the possibility of turning them on and off independently, but I guess we would all normally use them all on.

About the mentioned ones, this is how easy or hard they look to me at this point:
* Turn in the air: There are two things to this, which are making the car rotate in the air and actually make it start moving in another direction in the air. Both these things are easy to produce. What's difficult is to make the same cars have the ability as in Stunts while the cars that can't don't have it. That is, I would need to create a property in the RES files to actually account for this and it may happen that loading original cars would result in not the same cars having the feature unless they're edited. But yes, it can be done
* Legal shortcuts: This can totally be done and there are many approaches to this among which we can choose. As I progress with the engine, I'll come to you several times to propose things or ask and see what we like the most. The way Stunts calculates the track paths is super complex and I've been considering to de-automate it. That is, that the track designer actually has to set where the "checkpoints" are, so you can generate your own paths, even paths that go through places that don't look like continuous tracks. You can then be conservative and set lots of checkpoints following the track or you can be more liberal and place two checkpoints, one at the s/f line and another at the other extreme so that in the middle you can do virtually whatever you want. If you load a Stunts track, then no chance: it'd have to be automatic. I'll have to figure out how. But one thing is certain: I don't know the exact algorithm so the paths might be calculated differently.
* Powergear: Of course!  This one is very easy to reproduce. I could even follow the instructions in the wiki to ensure it happens with the same cars as in Stunts. But I am more inclined towards creating a new RES parameter where one could control if a car will have PG and what type.
* Magic carpet: It also seems straightforward, but I'm not very familiar with which cars can do it and under which circumstances. I tend to take these things as some magic that happens sometimes, so I'd need some input on that to be able to make them more faithful to the original Stunts.
* Drivable non-track objects: Of course. As long as you define its surface as drivable when you create the physical part of the shape. Probably it would depend on the slope too. Like, no surface with a higher slope than a certain value would be drivable.
* Car builder and parameters: As I mentioned, I would like to make it possible for one to actually configure as many details as possible, including the crazy features as part of the car, so this is something we won't miss. It should't be hard.
* Jesus Power Gear: This is a great idea I hadn't thought of!  The most similar existing Stunts feature/bug is the "fence-riding" one. Adding this is as easy or hard as the other configurable parameters. It's actually simpler than say, the magic carpet, because the car just has to go straight. Of course, it should remain above a certain speed or something like that.
* Flying objects: Uhm... I was thinking the whole physics engine based on parameters like those of Stunts cars. This would require something extra, like non-friction-based propulsion and steering. I don't see why it can't be done, but it's a whole different thing from the rest. I'm thinking balloons would be good for setting up cameras there. I'll make sure to make the engine leaving a "space" for this to be possible.
* More jumps and aerial stunts: Creating new stunts, like creating new scenery objects, can be done easily with the difference that for the former, you'd have to define the physical shape and drivable surfaces. I'm still struggling with a surface driving problem I've been asking Duplode about in an e-mail. I have to solve that to have a physics engine at all. With that solved, this should be easy too.
* Car easily crashed or uncontrollable: This was something I hated about Stunts when I first had it, but with time, I became used to it to the point that other car games sometimes feel toy-like to me, ha, ha. But yes, there are occasions when they are super annoying, like when you fall exactly between two elevated road pieces and your car breaks because you somehow hit a one micron high wall XD  I think this will naturally not happen in my engine. I hope.

[alanrotoi]

Nice compilantion and explanation. I can't reach that english level, sorry  . About the flying objets I thought a motionless zeppelin for example. The idea is (and we have another point here):

- 90º driving possibility: the chance to drive in 90 degrees in objects to add speed or change direction.

- About multi-height maps, it would be nice to have underground tunnels, more or less like the pipes. Hey! Also aereal pipes would be nice

[Daniel3D]

About the flying objets I thought a motionless zeppelin for example.

- About multi-height maps, it would be nice to have underground tunnels, more or less like the pipes. Hey! Also aereal pipes would be nice

Zeppelin's could be static in the air, as bouncing pad. Or as support.

I like the pipeline Idea. I had thought of the tunnel underground, but the pipe is a cool Idea.

[CTG]

About the flying objets I thought a motionless zeppelin for example.

- About multi-height maps, it would be nice to have underground tunnels, more or less like the pipes. Hey! Also aereal pipes would be nice

Zeppelin's could be static in the air, as bouncing pad. Or as support.

I like the pipeline Idea. I had thought of the tunnel underground, but the pipe is a cool Idea.

http://forum.stunts.hu/index.php?topic=2235.msg52234#msg52234

[Daniel3D]

About the flying objets I thought a motionless zeppelin for example.

- About multi-height maps, it would be nice to have underground tunnels, more or less like the pipes. Hey! Also aereal pipes would be nice

Zeppelin's could be static in the air, as bouncing pad. Or as support.

I like the pipeline Idea. I had thought of the tunnel underground, but the pipe is a cool Idea.

http://forum.stunts.hu/index.php?topic=2235.msg52234#msg52234

You are as always way ahead of us