[Fixed - persists in 3.70beta1] movement slow while zoomed in when snow crust

[Plotinus]

I used the arch 3.70b package on Manjaro Linux, I have 8GB of RAM and 3.3 GHz CPU. Resource usage looks okay, urw's only using 5% of my cpu, and the memory usage is also fine.

In the character creation menu, everything is fine and the game responds instantly to keypresses. However once the character loads, it takes 1000 miliseconds to respond to each movement keystroke, literally five seonds to walk five spaces forward, and turning around is slow too.

Things that I have tried that didn't make it faster - i exited the game completely between each of these changes, then undid them before trying a new one:

• changing SPEND_DELAY_ADD to be 1 (instead of 10)
• changing OLD_HARDWARE_MODE to be YES (instead of NO)
  
• [changing SCALE_QUALITY to 0 (instead of 2)

things that helped a little bit now it takes 300ms to respond to a keystroke, which is still pretty slow:

• changing idle animation to be NO (instead of YES)

I would've tested map lighting effects but I already had that turned off.



Things that are fast:

• character creation
• F6 map, including typing markers
• character inventory
• F4 scrolling through spells
• naming an animal
• walking and turning on the worldmap

Things that are slow:

• walking, turning around while zoomed in
• F3 examining tiles

UPDATE: I loaded a different character where it is summer and the movement is fine. The character that was experience slowness was in Swidden, waist deep snow, solid crust

[Plotinus]

New update: I loaded up a character for whom it is Soil month. There is thigh deep snow and no snow crust. The game is as fast as normal. So I think I've narrowed it down to something about checks involving movement on snow crust taking a long time on Linux.

[Plotinus]

It might be more complicated than that. I'm playing with a third character now, a migrated character where it's Early Center month and there's a snow crust on knee deep snow and everything's fine. I can provide a saved game of the brand new character, Egel, that inspired this post.

I thought it might be that Egel doesn't have skis (the soil month and center month character do) but I took off the skis and it wasn't slow for this migrated character either.

[ineedcords]

I too have experienced delayed response to key presses on Windows 10 so I think it could be due to the game code rather than platform specific performance regression or a library etc.
I have zero data on this though and that's why I have not submitted a bug report on this yet.
If devs ask for any testing/reports happy to do so & report back on the Windows side while Plotinus covers linux end.

[Plotinus]

What are the circumstances it's happening for your character? Time of year? What is your character trying to do? Is it a new character or a migrated character from the previous version?  Maybe we can narrow it down where the problem is.

[Erkka]

Also, just to confirm: is the character alone in the zoomed-in map, or are there a number of other creatures also moving around?

[ineedcords]

Also, just to confirm: is the character alone in the zoomed-in map, or are there a number of other creatures also moving around?

In my case, (1) it was in zoomed in map (2) it was me moving plus 12 dogs, 4 bulls, 1 sow.

[Plotinus]

Also, just to confirm: is the character alone in the zoomed-in map, or are there a number of other creatures also moving around?

Egel has a large pet reindeer, starting scenario Not all who wander are lost, spring start.

But my other character Behtter who didn't have the problem had two reindeer and a dog.

[ineedcords]

What are the circumstances it's happening for your character? Time of year? What is your character trying to do? Is it a new character or a migrated character from the previous version?  Maybe we can narrow it down where the problem is.

Mine is a character that has been created on 3.63 and migrated to 3.70b.
It was beginning of summer with snow still on the ground and ice on rivers.
I have a camp rapidside; in that tile there is a shelter on the ground, a cellar, a few timber (slender/tree trunk/branches etc) and nothing else (i.e. it's not my main camp with many items on the ground).
In zoomed in map, I was coming back to this shelter tile, by moving eastward after spending a day peeling bark.

As I played on, I got further into the summer and I currently don't seem to have any slowness. It is now Seedtime month and obviously no snow left on the ground.
Operating under the theory this all has to do with snow crust calculations, it all makes sense that it is back to "normal/responsive" state now. I might see it again next winter.

[Plotinus]

I had a thought it might be related to rendering all those little fires in the not all who wander are lost, so, with yet another character, where there is calf deep snow and a thin crust, i lit 11 fires in an open mire with one slender trunk each. but this didn't cause any noticable slow downs.

I do think it's something about the snow crust but it's not as simple as it first looked.

[Sami]

Plotinus, or anyone who's experiencing this,

if you have a savegame where this lag can be experienced feel free to send it.
Make sure that it really works reliably so that the lag is there for you even if you save and re-load the character.

[Plotinus]

I checked and it is still slow, so I've sent him to you. Thanks for looking at him for me.

I no longer think it's about the snow crust -- none of my other characters are having this problem

[Sami]

With great certainty the cause of this has been found, with the help of Plotinus' savegame.
It's not about crust. It's about line-of-sight checks where see-through visibility of saplings is checked in clumsy and slow way. It's not a problem normally but in case of many fires (and some other situations too) the line-of-sight checks accumulate in such a fashion that builds up little lag check-by-check, and finally the critical mass is reached where the game becomes all too slow.
To make the sapling see-through checks faster we can fix the issue.
The new beta and thus the remedy is expected to be released next week.