[kovarex] [0.17.66] Train waypoint reached even if disabled or removed

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boskid
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[kovarex] [0.17.66] Train waypoint reached even if disabled or removed

Post by boskid »

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Train contains following schedule:
- R (station on far right end)
- WP (waypoint, one with lamps and horizontaly aligned one below)
- L (stations on left)

upper WP is disabled when train can still repath to lower branch, but when train logic is already one schedule entry ahead.

Issue: train chooses upper path not conforming to schedule (it never reaches WP that is in its schedule)
Expected: disabling waypoint that is "partialy reached" (train did not reach it yet but is planning its route ahead) should force path recalculation and train should go by lower branch.

Same issue is when station is removed (instead of disabling it)

If i build isolated track and start placing rail signals in it, it will in fact force train to repath and it will choose lower branch.
wpfix-on-repath.gif
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quale
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Re: [0.17.66] Train waypoint reached even if disabled or removed

Post by quale »

I’m going to disagree that this is a bug. The train is committed to the WP station once its braking point has passed it, much like attempting to close a yellow signal won’t have any effect without a repath. I don’t think you should expect to change anything within the braking distance. If anything, it’s weird that repathing can force things that are ordinarily impossible. That seems to be more of an incidental convenience to both players and programmers than a solid design principle you should rely on.

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boskid
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Re: [0.17.66] Train waypoint reached even if disabled or removed

Post by boskid »

quale wrote:
Sun Sep 01, 2019 3:31 pm
I’m going to disagree that this is a bug. The train is committed to the WP station once its braking point has passed it, much like attempting to close a yellow signal won’t have any effect without a repath. I don’t think you should expect to change anything within the braking distance. If anything, it’s weird that repathing can force things that are ordinarily impossible. That seems to be more of an incidental convenience to both players and programmers than a solid design principle you should rely on.
boskid wrote:
Sun Sep 01, 2019 11:37 am
Same issue is when station is removed (instead of disabling it)
75143-remove.gif
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My question then is: which WP train managed to pass?

Second question: why even bother going through WP since it would be easier to repath and choose lower leg that has less penalty when going to station L?

quale
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Re: [0.17.66] Train waypoint reached even if disabled or removed

Post by quale »

boskid wrote:
Sun Sep 01, 2019 3:44 pm
My question then is: which WP train managed to pass?

Second question: why even bother going through WP since it would be easier to repath and choose lower leg that has less penalty when going to station L?
It passed the WP it remembered being there.

I don’t know too much about repath mechanics. I think the technical reason a repath doesn’t happen is that the train is already looking ahead at the L station, its braking distance having passed WP. L is now the only station that can trigger a repath if touched. If the devs decide it’s a bug, this is what would have to be changed.

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Re: [kovarex] [0.17.66] Train waypoint reached even if disabled or removed

Post by Klonan »

I would say, this is at best a minor issue,
I don't think it is worth looking into

I will leave this here for kovarex to determine the final reponse

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Re: [kovarex] [0.17.66] Train waypoint reached even if disabled or removed

Post by kovarex »

Not a bug.

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