Water Ski Tow Line Glitch

[AlyoshaTAS]

Hi,

 

I noticed this really obvious tow line glitch occur in both my emulator and the newly released A7800 emulator.

 

 

But, I can't determine anything that is wrong with emulation that would cause it.

 

So I am wondering if maybe this occurs on real hardware as well? If anyone has this game and might be willing to confirm if this glitch happens on console I would be appreciative.

 

Or, if this is already a known glitch and there is a reference as to what is happening that would be helpful too.

 

Thanks!

[+Mitch]

I do not recall seeing that on a real 7800 though it has been a while since I have played it.

 

Mitch

[Trebor]

I do not recall seeing that on a real 7800 though it has been a while since I have played it.

So I am wondering if maybe this occurs on real hardware as well?

 

It occurs on real hardware. This came up a few years ago while testing some hardware. Confirmed occurrence on an AT84, A1, and A3 serial.

[AlyoshaTAS]

Ah ok thanks for the info. It seems strange that they would release a game with such an obvious bug, but if that is the case then so be it.

 

At least I know I don't need to try to 'fix' it.

[Trebor]

Ah ok thanks for the info. It seems strange that they would release a game with such an obvious bug, but if that is the case then so be it.

 

At least I know I don't need to try to 'fix' it.

 

Strange (or sloppy/rushed) to release the game with such an obvious bug, indeed, there is no need to try to 'fix' it:

 

https://www.youtube.com/watch?v=Xp-2Sj78hnU

 

[+Mitch]

Weird, I don't remember ever seeing that. Obviously my memory isn't what it once was...

 

Mitch

[CPUWIZ]

Crap, who knows, maybe he is running it from my MCP cart and it is causing it? I believe everything you tell me about the 7800 these days. LOL

[Trebor]

Crap, who knows, maybe he is running it from my MCP cart and it is causing it?

 

No, sir...

 

The recent capture above is from a Water Ski cart playing back on an 'AT84 Serial' last night.

 

However, the "testing" part I mentioned was when you were designing the multi-carts. It was noticed to occur on them, and then I double checked an original cart on the various original hardware consoles.

[+-^CrossBow^-]

Now see...I have an AT84 serial unit and do not recall ever seeing this before either. I will have to load up the rom on my Mateos cart later in addition to the Anniversary #2 cart to test this.

[Trebor]

Now see...I have an AT84 serial unit and do not recall ever seeing this before either. I will have to load up the rom on my Mateos cart later in addition to the Anniversary #2 cart to test this.

 

Interested to know the results; if it does not occur at all, it wouldn't be the first (or the last) time there are mixed results with consoles of the same serial line.

 

It may be a tad surprising in the case of the glitch never happens though, considering the same effect is seen on an A1 and A3 serial console as well.

 

*EDIT: Another capture to demonstrate the glitch under original real hardware; this time during The No Swear Gamer's video @1:17. It can also be noticed several other times throughout the playback:

 

[Shawn]

Would it be very difficult to fix this glitch?

[RevEng]

I think it would require a fair bit of disassembly and analysis. I took a quick look, and I don't believe it's a hardware timing glitch. I believe there's a condition that the game isn't correctly accounting for in the very first frame of a 0-angle transition. (negative to positive, and visa versa)

 

The assembly code quality doesn't appear to be first rate. Lots of beginner type stuff like "and #$f0" followed by 4x "lsr" shifts, unnecessary register value reloads, and the like. I'm guessing the logic will wind up being a lot more spaghetti than usual, and I'm a bit overcommitted right now to take this on.

 

If anybody is interested, the rope angle setting/drawing routine is at 9CAE.

[Jinks]

Hmm. Never noticed anything with this game with the real cart and also the concerto.

[KevinMos3]

There are a lot of things that are out of alignment in this game. I realigned parts of the shoreline in my color & title screen hack a few years ago, but I didn't notice the tow line. It may be fixable by just moving the tow-line sprites to the left or right by a pixel, without even addressing any coding. I'd like to look at it sometime, but maybe someone else can get to it before I do. :-)