[0.17.66] Rail signals for reserved blocks change to circuit-closed state when train re-paths

Things that has been reported already before.
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farcast
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[0.17.66] Rail signals for reserved blocks change to circuit-closed state when train re-paths

Post by farcast »

If the close condition of a rail signal becomes true while the block is reserved (not occupied), and the train that reserved those blocks re-paths, the rail signal will change to the circuit-closed state.

This can lead to trains stopping instantly, and inconsistent circuit output behavior (assuming 74862 isn't also a bug).
Rail_signal_circuit_close_on_repath_bug.gif
Rail_signal_circuit_close_on_repath_bug.gif (2.2 MiB) Viewed 1670 times
Trains are running on nuclear fuel, and the game was running at half speed using the editor tool while recording.

How to reproduce:
  1. Build the attached blueprint.
  2. Fuel trains with nuclear fuel and set to automatic.
  3. Turn on the constant combinator at Start.
What I expect to happen:
The lamp in the top example should stay on as long as the train has reserved, or occupies, the middle block.
The train in the bottom example should move without stopping.

What happens:

Top example:
  1. Train reserves the middle block.
  2. Topmost rail signal becomes red, and its closed condition becomes true.
  3. Lamp turns on.
  4. Train stop point hits red rail signal, causing train to repath.
  5. Topmost rail signal switches to circuit-closed state, and stops outputting a circuit signal.
  6. Lamp turns off, even though nothing has changed about the state of the middle block.
Bottom example:
  1. Train reserves the middle block.
  2. Left rail signal becomes yellow, and its closed condition becomes true.
  3. Train stop point hits red rail signal, causing train to repath.
  4. Left rail signal switches to circuit-closed state.
  5. Train instantly stops at Left rail signal.
Efficient inefficient design.
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kovarex
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Re: [0.17.66] Rail signals for reserved blocks change to circuit-closed state when train re-paths

Post by kovarex »

Hello, there are several situations, in which train is able to stop faster than normal.

This specific problem would be solvable by not allowing the circuit network to "tap" the signal, until the new path and reservation has been finished.
This and other related problems are all solvable, but it is not worth the trouble, as the player encounters it very rarely and we want to finish the game before retirement.
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boskid
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Re: [0.17.66] Rail signals for reserved blocks change to circuit-closed state when train re-paths

Post by boskid »

Moving to Duplicate as it should be fixed for 1.1.0 by 90015
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