Does ac reduce spell damage?

[kuniqs]

I've came across a fresh reddit thread where people were advicing against raising your resistances by sacrificing ac - they said ac also reduces fire damage etc.
I call bullshit, but crawl has gotten some changes since I last played it (ranged combat is the same as meele) so I'm confused a bit.
Does ac reduce elemental spell damage? Does GDR apply to ranged damage now?

[Sprucery]

1. AC reduces incoming damage from most sources by 1d(AC+1)-1. This occurs before resistances. This can reduce it to 0. You might still get poisoned, banished etc. though. Some electric attacks (such as shock, lightning bolt, electric eel blasts) only check half of your AC.

2. Torment, smite, and hellfire, electrocution, and a handful of other abilities/effects ignore AC. The only player-castable damage spells that ignore AC are freeze, refrigeration, sticky flame, static discharge, pain, vampiric draining, Olgreb's Toxic Radiance, ignite poison, and agony. Note that all of these spells also ignore EV.

[kuniqs]

Why thank you mister.

[Sprucery]

...also, GDR still only affects melee attacks.

[and into]

In terms of the question on that reddit thread, though, it depends. Giving up a little AC, on a character that already has good overall defense (HP, AC + EV, SH), for a resistance that is very useful for the area you are currently in... That can be worth it. Just keep in mind you are trading something that mitigates nearly *all* damage for something that only helps against a much smaller subset of attacks.

Also keep in mind that the first pip of rF+/rC+/rN+ gives more benefit than the next one, so sacrificing other defenses for your second pip is almost never worth it.

[Sar]

rN is 33%/66%/100%

[Arrhythmia]

rN is 33%/66%/100%

No, it's 50%/75%/100%

[Sharkman1231]

Really? It seems like that went in a year ago. Now I feel a bit better about the first level of the Black Mark mutation.