The issue is: pistons powered in certain way don't act at all for no reason i can understand.
On the attached screenshot i showed some concraptions that uses very specific way for powering (when you place a block in front of piston, it pushes
that block across, making redstone powered for short amount of time (too short to unpower redstone torch))
if i'd attempt to explain this behaviour it would be that redstone that goes trough piston that unpowers it stops redstone giving block updates to next pistons (but still will power things like lamps)
On screenshot i marked pistons that got activated and those that didn't
link to save file https://www.dropbox.com/s/zzvqz6u1l251eo5/piston%20bug.rar?dl=0
Attachments
Comments
migrated
migrated
I'd say duplicate of MC-11193.
When the redstone dust turns on, both pistons receive an update. If the piston with the block in front gets powered first, it pushes the block away, turning the redstone dust off. As the 2nd piston tries to act on its update, it is no longer powered, thus not extending. The order is somewhat random.(MC-11193)
If you want to ensure that other pistons get powered first, you have to BUD-power(MC-108) the piston that turns the redstone off and update it with another piston.
On your 2nd contraption, you don't power the piston, while on the 3rd contraption it works because the block you place turns the dust beneath it into a dot.
Redstone torches and comparators need a longer signal; redsone lamps and repeater turn always on.
(For redstone torches see [MC-6099] last comment)
migrated
Please remove this report as a duplicate of MC-11193
MC-11193 shows incorrect update of contraptions using trough-block powering, while here:
I power pistons directly,
This bug happens ONLY with pistons
Your explanation is better than mine but not explains what happens in my last contraption, where both pistons marked get the same signal length but only one retract
(edit) may be considered a duplicate of MC-6099
migrated
Please describe the issue in detail. Your description does not make things very clear and the screenshot doesn't help, especially with things placed at different heights.