Circular distances cuts diagonal reach attacks short

[chaosvolt]

Describe the bug

It's the classic, a bug that has been in Cataclysm in general probably for as long as circular distances have existed. When using a reach weapon, trying to aim 2 tiles diagonally won't work if circular distances is on, cutting it off with only 1/2 range. This is of course inintuitive to the player who's expecting their spear to work within what seems to be the correct distance (instead of having to be conscious about whether they're a knight's move away or dead ahead instead), and is inconsistent with behavior when circular distances is off.

Steps To Reproduce

1. Load up with circular distances turned on.
2. Spawn in and wield a spear.
3. Hit f and attempt to aim due diagonally in any direction.
4. It will stop you at only a range of 1/2.
5. Turn circular distances off.
6. Observe you can now attack 2 tiles away in that direction.

Screenshots

Versions and configuration

• OS: Windows
  • OS Version: 10.0 2004
• Game Version: 6dcdd71 [64-bit]
• Graphics Version: Tiles
• Game Language: []
• Mods loaded: [ Bright Nights [bn], Arcana and Magic Items [Arcana], Cataclysm++ [Cata++], C.R.I.T. Expansion [crt_expansion], Elevated bridges [elevated_bridges], Medieval Mod Reborn [Medieval_Mod_Reborn], MST Extra [MST_Extra], Arcana/Cata++ Patchmod [Arcana_Cata++_Patch], Arcana/C.R.I.T. Patchmod [Arcana_Crit_Patch], Mining Mod [Mining_Mod], Tankmod: Revived [Tankmod_Revived], No Fungal Monsters [No_Fungi], Disable NPC Needs [no_npc_food], Faster Stamina Regen [stamina_regen_buff], Manual Bionic Installation [manualbionicinstall], Nonperishable Overhaul [Nonperishable_Overhaul], Simplified Nutrition [novitamins], SpeedyDex [speedydex], Stats Through Kills [stats_through_kills] ]

Additional context

I attempted to look through the code to fix this myself but had no such luck.

[Empyrean-Heaven]

Maybe this would help? https://github.com/CleverRaven/Cataclysm-DDA/pull/34749

[chaosvolt]

That was merged before the divergence point Coolthulhu updated BN to before reviving the fork (may 2020), so no.

[chaosvolt]

Just tested DDA (build 2023-05-08-0408) and of course they still have the bug. :V

Looks like they've went the route of "actually attacking 2 tiles away is an exploit" as per: https://github.com/CleverRaven/Cataclysm-DDA/issues/16400#issuecomment-214458037

The inability to attack the squares in the corners of the box surrounding the player is intentional.

[kholat]

It is a question of rounding. A 2 tile reach attack means it has a reach of 2 tiles of distance in cardinal directions, but if you attack 2 tiles diagonally, that would mean 2*sqrt(2) which is closer to 3 than 2, I suppose this is why the devs have chosen 1 is the better rounding option and therefore marked "intentional". (from 1.41 to 2 is cca 0.6, from 2.82 to 2 is cca 0.8)