Talk:Half physical damage

I'm mentioning this because I have seen it in spoilers before; from what I see in mhitu.c, half physical damage would not stack. The game simply checks for the property; if you have it, it divides the damage taken by two. Therefore, having two half physical damage artifacts would have no benefit. Granted, this is extremely unlikely in vanilla nethack, as one would have to have changed alignment somewhere to carry both the Master Key of Thievery and the Orb of Fate at the same time, but in SLASH'EM this is relevant, what with the addition of the Gauntlets of Defense and the Hand of Vecna, both of which can easily be gotten by one character.

It would seem that the same should hold true for half spell damage. However, half spell damage and half physical damage may stack with each other, I'm not sure. This would be worth investigating, which I may do later. -Ion frigate 01:07, June 10, 2010 (UTC)

From looking at the source, half spell and physical damage work the same way, just checked at different times (naturally). If set, then the damage is reduced to one half, rounding up. As you said it only checks for the property being set, so it does not stack.

Half physical and half spell should work fine together. Since the orb of fate confers both, it'd be kinda silly for them not to work together, wouldn't it? -- Qazmlpok 01:28, June 10, 2010 (UTC)

Well my question is whether or not damage from effects such as psi bolt and geyser is reduced to 1/2 or 1/4 if you have both properties. It seems that it's only ever 1/2, from looking at the source. Anyway, I think I'll add this to the article. For example, it makes half physical damage artifacts not as desirable in SLASH'EM, since anybody can get the Hand of Vecna fairly easily with a few burned Elbereth squares, and that gives half physical damage as well as hungerless regeneration. -Ion frigate 05:42, June 10, 2010 (UTC)

Oh, that's what you meant. That'd only happen if it checked for both at once, and I don't think it ever does. There's nothing absolutely preventing it from working that way, it simply doesn't. On a minor additional note, breath attacks are not subject to half spell (or physical) damage, according to a comment in zap.c. -- Qazmlpok 11:35, June 10, 2010 (UTC)

How much detail to keep?

64 new footnotes. And I did not even review them.

I do not want to prepare the 3.4.3 or the 3.7 sections of this article.

Thinking about deleting most of the "covered" section. The "uncovered" section is based on one good informative source code comment and that one reference provides lots of value.

Also note, the previous version of this article did not even say whether half physical damage applies before or after damage reduction from armor class. (Answer: damage reduction from AC applies first.) That is far more important for strategy than knowing whether an arrow trap is covered.

What do you think? Furey (talk) 01:47, 7 July 2024 (UTC)

My inclination is "most sources of physical damage except:" and then list the uncovered ones currently. Wondering if there's any other angles I might be missing. --Umbire the Phantom (talk) 08:49, 9 July 2024 (UTC)

Mitre of Holiness vs shapeshifted vampires

It's true that vampires are M2_UNDEAD, but only when they are not in shapeshifted form.

Here's the code: https://github.com/NetHack/NetHack/blob/NetHack-3.6.7_Released/src/mhitu.c#L1705

      if (dmg) {
        if (Half_physical_damage
            /* Mitre of Holiness */
            || (Role_if(PM_PRIEST) && uarmh && is_quest_artifact(uarmh)
                && (is_undead(mtmp->data) || is_demon(mtmp->data)
                    || is_vampshifter(mtmp))))
            dmg = (dmg + 1) / 2;

is_undead is false for a vampire in shapeshifted form (a vampire bat, fog cloud, or wolf), but is_vampshifter is true. So the Mitre of Holiness does not provide HPD for a wolf, but does provide HPD for a vampire shapeshifted into a wolf.

In many ways a shapeshifted vampire still behaves the same as unshapeshifted vampire, but in other (not documented) ways, it does not.

The vampire article and the vampire monster class article don't explain this very well. Furey (talk) 01:45, 10 July 2024 (UTC)