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edward406
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Broken Timer
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So I found a way to abuse the timer in F-Zero (the NTSC version atleast). I'll start with how I found this trick.

Last night, I was doing a few runs on some of the practice tracks, and as I sometimes do, I wasn't recording. After playing Port Town II a bit, I started to have a good run. Just as I come up to the finish, I pause the game. The timer reads 2'11"58 and I'm right near the finish. I figure I may as well record it from here just for record keeping in case it's a new time (not as an actual video proof though). Before recording, I'm guessing how many frames from the finish line I am. It looked like two, but it also looked close enough that it could be one. If it was one, it had to be a 2'11"59 or 2'11"60. I start recording, hit start, and get a 2'11"60, and I figured, "nice, a new best." Afterwards, I go to examine my video just to see at what point I crossed the line. I start advancing frame by frame. The timer first advances from 2'11"58 to 2'11"59... I advance one more frame, the timer goes to 2'11"60 and the race is over.

Immediately I knew something was wrong. I knew no matter what, the timer is supposed to advance "03 every 2 frames. I couln't understand how the timer advanced "01 two frames in a row. I did a TAS after this to see how this happens. It turns out, that even when paused, every frame the game must be switching the value for what gets added to the timer. What this means is how long you pause for can effect how the timer advances on the second frame after unpausing. I say the second frame, because, the first frame (for whatever reason) is always consistent with what the timer last advanced.

So if the timer advanced "02 the last frame before pausing, it will always advance "01 the next frame the game advances after unpausing and vice versa. Now, if the game was paused for an odd number of frames before unpausing, the game remembers that it is supposed to advance "01 on the 2nd frame after unpausing, so even after advancing "01 on the first frame, it does it again on the second frame.

It was after this that I realized this trick could be used to slow the timer down.

I made a TAS showing how much time can be removed.

Now for a normal player, using this trick would be somewhat similar to playing roulette and betting on black or red. The reason being that it is obviously too difficulty to know when to pause the game so that the last frame has advanced "02, and then unpause it after an odd number of frames.  Based on how the odds work, it is more likely that this trick will cancel itself out. i.e. the odds of advancing "01 two frames in a row are the same as advancing "02 frames in a row. Ulimately though, with enough luck, this trick can be used to remove potentially significant amounts of time from the timer.

Technically this trick is not cheating, so it certainly isn't against the rules. That being said, I also think it's a bad idea to allow as it's entirely lucked based and can be used to unfairly remove time. I'm thinking it would be best to make it so that if you submit a time, that the use of the pause button cannot be allowed in a run, otherwise it is disqualfied.

"It's the F-Zero spirit!" -Yazzo
samurai goroh
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First thing that came into my mind when seeing this topic was that you used pause to rig the time and seems I was right.

More than just banning pause, doesn't the trick only work when you do it consecutively?
Because you might want to pause the game each time you cross the finish line to check your time, and with this rule you aren't allowed...

edward406
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samurai goroh wrote:

First thing that came into my mind when seeing this topic was that you used pause to rig the time and seems I was right.

More than just banning pause, doesn't the trick only work when you do it consecutively?
Because you might want to pause the game each time you cross the finish line to check your time, and with this rule you aren't allowed...

It is possible to do without doing it consecutively. I made a quick video showing what happens when a human player tries it.

In the first instance I reduced my time a little, and in the second instance some time was added. For the most part though, it cancels itself out. There are four outcomes that can happen to the timer when pausing and unpausing. Of those four, two of the outcomes will have the timer advance normally as if nothing happened. The other two outcomes will either add "02 twice, or "01 twice. If playing a race, you would probably only pause four times to check the timer. The odds of getting "01 added twice all four times would be 1/256 (1/4 x 1/4 x 1/4 x 1/4).

Though the odds are very small, I believe it shouldn't be allowed so as to prevent any luck from being added to runs. I understand this is a crappy thing as some people depend on pausing the game to check their splits. That being said though, no video proof is required unless the time is a FZC Best/WR, so there would be no way for FZC staff to know anyways. However I would still strongly encourage not doing the trick as it does allow for the possibility of unintentionally altering your time.

If people who are competeing on the ladder would still prefer to be able to pause at least four times to check their lap time, they should speak up as I wouldn't mind it. Otherwise it will be an all out ban on pausing during NTSC runs.

If people don't want an all out ban for the ladder, I feel there should at least be a ban on pausing when submitting for a WR/FZC best runs. "04 can make all the difference in making or breaking a WR run, and there is no sense introducing more luck to the equation when it is possible to avoid.

"It's the F-Zero spirit!" -Yazzo
edward406
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Since I haven't heard any opposition to making pausing against the rules for a FZC Best/ WR run, I'm going to go ahead and add to the rules that if submitting a FZC Best or WR video, there can be no pausing of the game mid run. This rule will only apply for IL runs on the NTSC version (The PAL version timer is unaffected by pausing as the timer always advances "02 every frame) and for all times submitted after the date of this post, November 5th, 2014.

For people who are not required to submit video proof, it is only fair that this rule applies as well.

That being said though, when submitting times to FZC which are non FZC Best/WR's, you are submitting times on a basis of an honor system, therefore I can't actually enforce this rule on your times unless you willingly post videos of your runs.

"It's the F-Zero spirit!" -Yazzo
Uchiha Madao
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what a crappy glitch.

fortunately we had rules that required videos for WRs and site bests so adding the extra no pausing to them is easy.

"Patience is useful in any moment"
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