Extreme performance hit heading into city with 3d FOV enabled

[esotericist]

Describe the bug

While testing some changes to fix monster evolution erroneously increasing with changes in cataclysm start date, I went into town and found the game taking in excess of 1 real-life wall-clock second for every step, sometimes as much as 2 or 3 seconds.

Steps To Reproduce

Steps to reproduce the behavior:

1. Load attached savefile
2. Try to move around (waiting doesn't seem to have the same impact)
3. Watch it sluggishly attempt to do things

Expected behavior

Ideally, it should be just as fast in town as it is when out of town. With 3d FOV, some slowdown is probably inevitable, this seems a bit much.

Screenshots

Profiler!

Versions and configuration

• OS: MacOs
  • OS Version: Name: Mac OS X; Version: 10.14.5; Build: 18F132;
• Game Version: 0.D-5069-g6be2679ca8-dirty [64-bit]
• Graphics Version: Tiles
• Mods loaded: [
  Dark Days Ahead [dda],
  Disable NPC Needs [no_npc_food]
  ]

Additional context

Save file.
evolutiontest.zip

[esotericist]

Options, in case you need them:

options.json.txt

[Midaychi]

Shady Side.zip

Simply walk east to load in the farm multi-zlevel silos and observe this slowdown.

GAME REPORT:

• OS: Linux
  • OS Version: LSB Version: n/a; Distributor ID: ManjaroLinux; Description: Manjaro Linux; Release: 18.0.4; Codename: Illyria;
• Game Version: 0.D-5099-gdc2cc104eb-dirty [64-bit]
• Graphics Version: Tiles
• Mods loaded: [
  Dark Days Ahead [dda],
  Magiclysm [magiclysm],
  Bens GF recipes [Tolerate_This],
  Garden Pots [growable-pots],
  Medieval and Historic Classes and Shields [Medieval_Stuff],
  Mythological Replicas [nw_pack],
  Modular Turrets [modular_turrets],
  Salvaged Robots [Salvaged_Robots],
  DinoMod [DinoMod],
  Hydroponics [hydroponics],
  Mythical Martial Arts [MMA],
  sees-player icon, +attitude [sees_player],
  Urban Development [Urban_Development],
  More Locations [more_locations],
  Mapgen Demo [mapgen_demo],
  Fuji's More Buildings [FujiStruct],
  Beta National Guard Camp [national_guard_camp],
  Disable Mutagens [no_mutagen],
  No Survivor Armor [no_survivor_armor],
  Bionic Slots [cbm_slots],
  Sleep Deprivation [sleepdeprivation],
  NPC traits [npc_traits],
  Mutant NPCs [mutant_npcs],
  More Survival Tools [More_Survival_Tools],
  Vehicle Additions Pack [blazemod],
  Tanks and Other Vehicles [Tanks],
  Folding Parts pack [deoxymod]
  ]

[Midaychi]

as of dcd9f1d
one or more of the changes in the last day and a half has significantly improved performance around zlevel buildings when zlevel vision and zlevels are enabled. The speed isn't 100% to how it was before this issue cropped up but it's close enough that it's very playable.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. Please do not 'bump' or comment on this issue unless you are actively working on it. Stale issues, and stale issues that are closed are still considered.

[kevingranade]

This should be fixed by #32012
Overhauling the algorithm is certain to replace any existing errors with all new errors.

[kevingranade]

I'm removing this from the 0.E blockers because 3D_FOV is still not default-on, we will definitely be shooting for that for 0.FoV, and because we have basically no prospect of addressing it in a timely fashion.

[esotericist]

should be fixed as of #42835