Stunts 1.1 freeze glitch

[GTAManRCR]

Looks like 25 mins is the limit. I'm not done the track yet, but the game won't allow me to continue driving

[Daniel3D]

Did the game force you to stop driving? Or did you enter the replay file and played until the end?

[GTAManRCR]

The game forced me to stop driving

[GTAManRCR]

Tomorrow I'll try with 10 FPS too. This will likely 50 minutes of racing.
Conclusion: In normal simulation mode, Stunts 1.0, and 4-D Sports Driving lets you drive for 25 minutes, but Stunts 1.1 and 4D Sports Driving freezes after 10 minutes (After 20 minutes with 10 FPS mode). The question is: Why? Is this a bug with Stunts 1.1 source code?

[afullo]

Yes, the maximum is 25 minutes, since technically it would be 27:18.35 (32767 frames * 0.05 seconds/frame), then the time would overflow to -27:18.40 (-32768 frames * 0.05 seconds/frame, using 16-bit signed integers), with 25.00:00 being the nearest "sufficiently rounded" lower number; see here and here.

[Cas]

That is a good explanation!  We should test it with precise time measurement to verify if this is so. Also, we have to take into account that Stunts uses the old BIOS timer so one "second" in Stunts is surely not exactly equal to one real second. For a short replay, this isn't noticeable, but if you're driving for so long the odds are you'll find some discrepancy between an external, more precise clock and the internal time. The one that should break at exactly the value mentioned by Afullo is the internal clock, so it should display that time in the replay menu if it were possible to go there. Therefore, if measured only with an external clock, we can't be sure of how many frames were actually counted.

One thing we can do is measure how much "real time" it takes for Stunts to record a reachable, but large and well defined amount of time like, for example, eight minutes. Then extrapolate to estimate the actual number of frames when it crashes. It makes sense that the crash occurs as a sudden freeze with no system collapse, which would be the natural thing if it were a For loop starting from a negative number. I'm guessing that, if you were to wait for another 27 minutes to pass, the game would suddenly unfreeze and begin to overwrite the old frames. On the other hand, if it does crash with an error, it meas it is capable of overwriting at "negative" addresses relative to the segment where the frames are being stored.

[Duplode]

Following afullo's reasoning, I wouldn't be surprised if the 25 minutes limit were explicitly set in the code as 30000 frames. That would be similar to how the speed limit is set as 245 mph, with a little cushion before the unsigned overflow at 256/65536.

[GTAManRCR]

If we could unlock these limits and could drive for infinite amounts of time
I'd race for a day

[Daniel3D]

If we could unlock these limits and could drive for infinite amounts of time
I'd race for a day

The 24h of LeStunts

That would be one hell of a live race....

[Cas]

Something like that could be arranged. Or something a little smaller to try. For example, a pipsqueak plays the first 8 minutes in a way similar to that of LeStunts, then the other the pipsqueak in the "live team" is prepared to take over. When the first pipsqueak finishes, the second one starts and the first sends the replay for quick verification and so on. Maybe this could extend up to an hour. The problem is what to do with the partial laps.

[Daniel3D]

Hit escape at 8 min send replay to number 2, then upload it to forum. Nr2 continues on same replay then sends to 3 and uploads to forum. Number 3 drives until the 24 mark and uploads.

Or, 6 minutes 4 people.

[Daniel3D]

That won't work for more than 25 min. But no partial laps..

[afullo]

It could work with the versions of Stunts allowing to get past the 10 minutes threshold, since as shown in May 2018 the latest 10 minutes of race are stored in the replay. So, the partial (6 or 8 minutes) replays can be posted separately and checked after the end of the race.

[GTAManRCR]

Amiga version is the same -> 25 minutes limit with all two simulation speeds

[GTAManRCR]

Take one of the live races. You can drive the lap endlessly because start/finish is on a side track.

This is gonna off topic, but the opponents are completely idiots in Stunts 1.1, this track proves it. In Stunts 1.0, they can drive actually