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deedub777
22-09-2015, 20:27
Hello SMS,
hope this short example helps you track down the problems, good luck.

Track and other details shown in vid...


https://youtu.be/bIQvE79E_30

Roger Prynne
22-09-2015, 22:30
Have a read of this.... it might explain some things.

http://forum.projectcarsgame.com/showthread.php?39365-bmw-320-gr-5&p=1121559&viewfull=1#post1121559

SUBGTRACER
22-09-2015, 22:33
Hmmmmm just seems some times we are going around in circles :( and we don't have ovals !

deedub777
25-09-2015, 10:28
Have a read of this.... it might explain some things.

http://forum.projectcarsgame.com/showthread.php?39365-bmw-320-gr-5&p=1121559&viewfull=1#post1121559

well I read three pages of "I don't know what". One line answer then? How does a slight side to side alignment relate to a dead stop. - confused, sorry

deedub777
25-09-2015, 10:29
Hmmmmm just seems some times we are going around in circles :( and we don't have ovals !
I don't understand what you mean?

Vennt
25-09-2015, 12:26
well I read three pages of "I don't know what". One line answer then? How does a slight side to side alignment relate to a dead stop. - confused, sorry

The dev mentions they found an accumulation error with the simuation of the suspension, an accumulation error is a pretty nasty bug to find because often the steps to reproduce it are as hard to pinpoint as the bug itself, and you pretty much need to reproduce a bug to be able to find its cause and fix it.

A simple example of an accumulation error:

Lets say that your steering wheel position, when centred, is a 0, and every time you turn left a 1 is added to a counter, and every time you turn right a 1 is taken away from it, if you turned left once, then turned right once, the final number should be a 0 again(Start at 0, add 1 for turning left, take away 1 for turning right, puts you back to 0).

In an accumulation error, there could be a bug that instead of taking away 1 when you turn right, only 0.99 is taken away, so the first time you turn left 1 is added, then turn right 0.99 is taken away, and instead of being at 0 like you would expect, your final counter is 0.01, very close to 0 but not exact, the next time you turn left a 1 is added, and turn right again 0.99 is taken away your counter now reads 0.02, instead of 0, this is the "drift" the dev mentions, the numbers are drifiting from where they should be because the wrong amount is being added or taken away little by little, so an accumulation error can be thought of as a small bug that can, over time, have big effects.

Now errors that build up over time like this can be difficult to spot because if they only cause a problem after 30 minutes of play, and the dev tests the system out with only 20 minutes of testing, he may never see the bugs effects happen.

This is why when reporting bugs, it's best to give as much detail as possible, not just track and car, but playing session length, how long you were on track etc. because this makes the devs job of reproducing such problems much easier.

(Although I'd personally prefer to have to debug an issue like this than a type of 'bug' called a "Race Condition", which despite it's name isn't just a sim bug, it'is a type of timing issue with multithreaded programming where the timing between threads can get screwy and 'jammed', with this type of issue even just using a debugger to look at he code can solve it temporarily for the dev, so a dev can almost never actually reproduce the issue at all while looking at the code running, all very quantum, just looking at it affects it :P)

deedub777
25-09-2015, 13:19
@Vennt I really appreciate you taking the time to explain in context.

In the linked video it shows the event occurred 13m18secs into a qualifying session with 01:41 to go (so a 15 min quali session).
I was on lap 4 of my quali run. Laps were taking about 1:49 and I was 1:07 into the lap so (assuming outlap was about 2:10) total driving time was about 8:43.

During the race I was on lap 5 of 7 doing similar lap times to quali, high 1:40s.

Not sure how much more info I could've provided :)

VR-Mustard
28-09-2015, 23:31
https://youtu.be/yFJgbc1iHJo

Tell me again that this game isn't completely broken..

wyldanimal
29-09-2015, 03:56
The dev mentions they found an accumulation error with the simuation of the suspension, an accumulation error is a pretty nasty bug to find because often the steps to reproduce it are as hard to pinpoint as the bug itself, and you pretty much need to reproduce a bug to be able to find its cause and fix it.

A simple example of an accumulation error:

Lets say that your steering wheel position, when centred, is a 0, and every time you turn left a 1 is added to a counter, and every time you turn right a 1 is taken away from it, if you turned left once, then turned right once, the final number should be a 0 again(Start at 0, add 1 for turning left, take away 1 for turning right, puts you back to 0).

In an accumulation error, there could be a bug that instead of taking away 1 when you turn right, only 0.99 is taken away, so the first time you turn left 1 is added, then turn right 0.99 is taken away, and instead of being at 0 like you would expect, your final counter is 0.01, very close to 0 but not exact, the next time you turn left a 1 is added, and turn right again 0.99 is taken away your counter now reads 0.02, instead of 0, this is the "drift" the dev mentions, the numbers are drifiting from where they should be because the wrong amount is being added or taken away little by little, so an accumulation error can be thought of as a small bug that can, over time, have big effects.

Now errors that build up over time like this can be difficult to spot because if they only cause a problem after 30 minutes of play, and the dev tests the system out with only 20 minutes of testing, he may never see the bugs effects happen.

This is why when reporting bugs, it's best to give as much detail as possible, not just track and car, but playing session length, how long you were on track etc. because this makes the devs job of reproducing such problems much easier.

(Although I'd personally prefer to have to debug an issue like this than a type of 'bug' called a "Race Condition", which despite it's name isn't just a sim bug, it'is a type of timing issue with multithreaded programming where the timing between threads can get screwy and 'jammed', with this type of issue even just using a debugger to look at he code can solve it temporarily for the dev, so a dev can almost never actually reproduce the issue at all while looking at the code running, all very quantum, just looking at it affects it :P)


@Vennt I really appreciate you taking the time to explain in context.

In the linked video it shows the event occurred 13m18secs into a qualifying session with 01:41 to go (so a 15 min quali session).
I was on lap 4 of my quali run. Laps were taking about 1:49 and I was 1:07 into the lap so (assuming outlap was about 2:10) total driving time was about 8:43.

During the race I was on lap 5 of 7 doing similar lap times to quali, high 1:40s.

Not sure how much more info I could've provided :)

Length of Time.

Yes exactly my Point in this Post..
http://forum.projectcarsgame.com/showthread.php?39365-bmw-320-gr-5&p=1127455&viewfull=1#post1127455

The Dev ( Casey Ringley ) was talking that it shows up in LONG session times...
My Experience is that it happens in Short Session times, 5 to 10 minutes of actual on track time...

So I'm wondering if what the Devs found is different than what's causing the Landmine issues.

svenvangent
30-09-2015, 21:42
This one is also big fun :cool: https://www.youtube.com/watch?v=WSGSx2NraJw