why don't these pipes connect?

5 blocks further

Any tips?

is this still heapening?

Further investigation led to this:

Every engine has one orientation in which it doesn't connect to anything... But i've no clue what the actual direction depends on :/

Every engine rotated once further:

Well, kind of obviously, only wooden or emerald kinesis pipes connect to the front, but as for everything else... very strange.
@asiekierka
@AlexIIL

Somehow a world reload fixes it temporarily for me... however I'm not sure how this is happening. It doesn't seem to be a sync issue (connecting from a different client doesn't change anything).

yes unfortunately, and I haven't been able to work out what causes it :(

just noticed that optifine is involved in the second set of screenshots

is it possible that a (partially) incorrect blockpos is being passed allong in the checks if it can connect or not?

It happens server-side, and I have reproduced it without optifine so its not to blame this time.

Its possible that an incorrect blockpos is being passed along somewhere, but I haven't found it yet.

is this still an issue?

latest buildcraft-7.2.8 for 1.8.9 has same problem

euh not in that setup, that redstone engine is not suposed to connect to the wooden kinesis pipe because it proveds to weak power (becuase it's basicly free power)

also closing this as nobody else reported this heapening so should be fixed (as long as optifine isn't involved)

Well this is fixed in 7.99.x but not 7.2.x

yes but i don't think we will be doing anymore 7.2.x releases unless critical world devouring bugs pop up with the development being focused on the 8.0 branch

so no more 1.8.9 support?
perhaps possible run 7.99.x in 1.8.9 ?

correct, with the development being focused on 1.11 there is no 1.8.9 support at this time

that's very pity...
so.. me'll try to fix it myself.
maybe you can tell me where to look please?
me still new in java

if you want to try and fix it yourself and do a PR you are more then welcome to
as for where to look: the only thing i can say is look at the engine placement code and anything related

at some point an effort was made to fix this but none of the devs found the root cause, it is most likely an incorrect blockposs being passed somewhere or an incorrect shifing of it to check

@0142929 it's likely to be somewhere in https://github.com/BuildCraft/BuildCraft/blob/7.2.x/common/buildcraft/core/lib/engines/TileEngineBase.java, or in the methods related to it.

thanks very much!