[kovarex] [0.17.60] Items degroup between splitters

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sirOrangJuice
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[kovarex] [0.17.60] Items degroup between splitters

Post by sirOrangJuice »

Groups of items break up when going though splitters positioned like this:

Code: Select all

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Blueprint:

Code: Select all

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
Video:
downstream splitter.mp4
(8.9 MiB) Downloaded 154 times

Possibly related to viewtopic.php?f=29&t=65493

gabberworld
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Re: [0.17.60] Items degroup between splitters

Post by gabberworld »

yeah i see what you want todo at here, you want move upper stuff to bottom, bottom stuff to center and center stuff to up

sirOrangJuice
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Re: [0.17.60] Items degroup between splitters

Post by sirOrangJuice »

No. Since the items all arrive at the same time, I would expect them to pass through the splitters undisturbed. Instead the first copper and iron plate get ahead when passing through the first splitter.

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Re: [0.17.60] Items degroup between splitters

Post by slippycheeze »

sirOrangJuice wrote:
Wed Aug 21, 2019 9:43 am
No. Since the items all arrive at the same time, I would expect them to pass through the splitters undisturbed. Instead the first copper and iron plate get ahead when passing through the first splitter.
You should probably keep in mind that "the same time" vs at different times is not necessarily going to be visible to a human. It doesn't take much to be 1/60th of a second offset, and that'd give dramatically different behaviour. This is the root cause of many of the apparent but not actual "errors" where splitters generate different outputs for what look like the same inputs.

Splitters are strictly deterministic, the issue is that the inputs vary in ways that are imperceptible to a human, so they strictly deterministically produce apparently different outputs for apparently identical inputs.

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Re: [0.17.60] Items degroup between splitters

Post by tehfreek »

slippycheeze wrote:
Fri Aug 30, 2019 5:39 pm
Splitters are strictly deterministic, the issue is that the inputs vary in ways that are imperceptible to a human, so they strictly deterministically produce apparently different outputs for apparently identical inputs.
Normally I'd be right with you on that, but the debug info in the video shows the single sequence of items being split in two after the splitter so human perception needn't be involved.

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Re: [0.17.60] Items degroup between splitters

Post by sirOrangJuice »

slippycheeze wrote:
Fri Aug 30, 2019 5:39 pm
You should probably keep in mind that "the same time" vs at different times is not necessarily going to be visible to a human. It doesn't take much to be 1/60th of a second offset, and that'd give dramatically different behaviour.
This is why all items are released simultaneously using a timer.


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Re: [0.17.60] Items degroup between splitters

Post by boskid »

I am almost certain this is duplicate of 65493

In above example, issue is with lower left spliter and incoming transport lines. Bottom two lines are merged up to circuit controlled belt so they are almost always active with moving items. Items in middle belt (both lanes) degroup when they enter transport lines that is merged up to spliter and this makes this issue duplicate (at least in my opinion)

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Re: [0.17.60] Items degroup between splitters

Post by Jon8RFC »

Same thing? Paste in map editor, play, let the items catch up, then pause. Place one block of solid fuel on the outer edge of the circular belt for each set

Depending upon either where the solid fuel is placed or some tick coincidence if I place the solid fuel on at a later time than the other solid fuel, the belts with the purple chests on them either always gets a gap, never gets a gap, or gets a gap on occasion. They don't always behave the same and I couldn't readily figure out a rhyme or reason.
Image

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Re: [0.17.60] Items degroup between splitters

Post by boskid »

Jon8RFC wrote:
Thu Sep 05, 2019 4:35 pm
Same thing? Paste in map editor, play, let the items catch up, then pause. Place one block of solid fuel on the outer edge of the circular belt for each set
(bp)
Depending upon either where the solid fuel is placed or some tick coincidence if I place the solid fuel on at a later time than the other solid fuel, the belts with the purple chests on them either always gets a gap, never gets a gap, or gets a gap on occasion. They don't always behave the same and I couldn't readily figure out a rhyme or reason.
Your setup is not ideal.
1/ Placing solid on inner lane of your clock generator gives less ticks than placing it on outer lane
2/ In your setup, when there is gap, items start to change lanes hiding this gap creation and further reducing reproducibility and gives some randomness (that is: spliter state may decide if next item will go left or right lane, by simple picking up some items there may be different outcome)
3/ Issue is with spliter with merged input lines. To show this issue input line must be inactive for some ticks and then become active again: in this case, first item is moved by (what it looks like) one tick forward.
4/ With solid fuel on inner lane, timming is too short to trigger inactive lane periods.

Here is my reproduction that is based on my observations for 65493 and it works great: first item on inner belt is moved ahead by a lot. Because with them(observations) i was able to execute such big degroup, i assume this is duplicate (same reproduction for two different issues is quite unlikely)
73872-long-belt.zip
(200.55 KiB) Downloaded 40 times
73872-long-belt-begin.gif
73872-long-belt-begin.gif (729.23 KiB) Viewed 1476 times
73872-long-belt-end.gif
73872-long-belt-end.gif (645.5 KiB) Viewed 1476 times

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Re: [kovarex] [0.17.60] Items degroup between splitters

Post by kovarex »

Duplicate: 65493

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