Trap changes

[Mikko Lehtinen]

Sounds excellent! I've got no complaints.

[jevansau]

Sounds very good.

One way to deal with the magical side would be to change the locate trap spells to a "improve searching ability/radius for a turn" spell.

Have you thought yet about the other side of the problem - disarming traps?

It is exciting to see work in this long neglected area.

Regards,
Jonathan

[Magnate]

Having monsters set off traps wouldn't be too difficult. But how do you decide how likely a monster is to notice or evade a trap? And once you figure that out, you need a lot of storage if you want every monster to maintain its own list of which traps it knows about. Maybe it would be easiest to only allow "obvious" traps to hit monsters.

Sangband deals well with monsters' awareness of player traps (you don't mention those, so I presume they're not in this phase). But I don't think it uses a separate trap layer - I think there is some hackery that treats traps as objects.

FA, however, does have a separate trap layer, or rather a more generalised separate terrain feature layer. I understand it's really quite brilliant - not sure how easy it would be to borrow rather than reinvent.

A traps.txt file is excellent, and fits well with my ideas for effects.

[d_m]

Sounds like a great plan.

Personally I would remove the (s)earch command altogether, since under your scheme the "optimal" play is to travel until you hit the "search detection boundary" and hit s. But maybe it wouldn't be such a big deal.

Probably, the best thing to do is get it coded up and let us all playtest it!

[Gorbad]

If we assume CunningGabe's plan is followed and the s key is only effective once, a magical 'detection-aid' could also be a timed effect which:

a) increases you search skill and/or radius for a timed period and
b) gives a guaranteed warning if a trap is within your radius (just not where) for that timed period ('Spidey sense is tingling')

This would increase anxiety (a good thing!) and provide the player with a choice ("I've dropped consumables earlier on the level, better get them before I hit a trapdoor" or "How badly do I want to see what that unID'd potion is over there, I know the area is trapped").

[Mikko Lehtinen]

1. Each trap has a rating of how hidden it is. A rating of 0 indicates that it is immediately obvious. A positive rating indicates that the trap starts out hidden.

Are you planning to randomize the concealment rating? For example, a trap door could have a rating 1d20, rolled when the trap is created. This would prevent gaming the system to get "just good enough perception to detect trap doors".

3. Whenever a hidden trap is within your search range, if your search rating is at least as high as its hidden rating, then the trap is revealed. This is completely passive detection; i.e., it does not require you to 's'earch or to be in 'S'earching mode.
4. Whenever you 's'earch, you make a check to spot traps as if you were using passive detection, but your search range is increased by 1, and your search rating is increased by 20. As before, if your (modified) search rating meets or exceeds the hidden rating, then the trap is revealed. 'S'earching mode remains the same as before; i.e., when it is on, you make a 's'earch with every step you take.

I would personally like to see Wisdom increasing Perception.

In D&D 3rd edition, Wisdom is associated with passive perception and Intelligence with active searching. Maybe INT could affect how much perception increases when you are searching?

I don't really think trap detection spells are worth implementing unless they add some tactical depth to trap detection. If the correct play is to always cast trap detection spell when you leave your detection area, it becomes just boring "extra work".

In Fay, I'm moving effects like Protection from Traps to scrolls to make them a limited resource. That way the player has to make a choice.

Also, only some kind of rooms are trapped. If a room has closets, it also has lots of traps on the floor; if a room has painted walls, it may have dangerous warding runes.

[Mikko Lehtinen]

One way of implementing trap detection spells in a strategically interesting way, and without extra work for the player, is this:

You only need to cast trap detection once per level. If you do, the spell lowers your maximum mana and increases your detection abilities for as long as you stay on the level.

EDIT: I really like Gorbad's detection-aid spell with the Spidey sense!

[Mikko Lehtinen]

Maybe Searching mode should be changed to work like this: If you are Searching, you will automatically perform the search command whenever there is an unsearched square next to you -- unless you see a monster.

That way you could usually just leave the Searching mode on and not bother with it.

Of course then you would need to track the searched status of each square. Or maybe even track the perception skill score used to search each square. Then you would only search if your current perception skill is higher.

[Mikko Lehtinen]

I got an inspiration from this trap discussion.

I decided to add a monster ability SET_TRAPS. If a monster with SET_TRAPS is generated with the dungeon level (not summoned), it has put some traps in the nearby dungeon!

This replaces the Create Traps monsters spell.

[CunningGabe]

Are you planning to randomize the concealment rating? For example, a trap door could have a rating 1d20, rolled when the trap is created. This would prevent gaming the system to get "just good enough perception to detect trap doors".

That's a good point -- I'll introduce some variability into the hidden rating. I'm also thinking of using something like buzzkill's idea where a trap might be better hidden depending on where it is placed. Also, I am planning to give traps level ratings, so a vault would include out-of-depth traps, just as it does with monsters and items.

I would personally like to see Wisdom increasing Perception.

In D&D 3rd edition, Wisdom is associated with passive perception and Intelligence with active searching. Maybe INT could affect how much perception increases when you are searching?

One of the changes ewert made in his fork (and which I incorporated) was to make WIS and INT both contribute to searching skill. At the moment, they both contribute equally.

[fizzix]

Having monsters set off traps wouldn't be too difficult. But how do you decide how likely a monster is to notice or evade a trap? And once you figure that out, you need a lot of storage if you want every monster to maintain its own list of which traps it knows about. Maybe it would be easiest to only allow "obvious" traps to hit monsters.

Here's how I envision this

Obvious/unavoidable traps (example pits) If you enter this square you fall into the pit. You cannot disarm these traps, they are a feature of the dungeon. The best you can do is climb out the other side. Monsters always avoid these if possible, if not they just take the damage.

Obvious/avoidable traps (example turrets) Everyone can see this trap. However, you can avoid the effect with sufficiently high dexterity (or proper resistance). Again intelligent monsters avoid these if possible. If they can't, (and they're intelligent) they may attempt to disarm it.

Unobvious/avoidable traps. (example darts, teleportation squares) Entering the square will set off the trap. Monsters don't know about these, and don't bother avoiding them. You always get a saving throw against the trap. Monsters don't bother avoiding these, but get a saving throw just as a player. Generally monsters get a better saving throw than the player. These traps can be created by spells.

We could even include a "IMM_TRAP" flag for some skilled monsters like master thieves, master rogues, harowen, sauron, wormtongue, etc. These monsters never set off avoidable traps, and always succeed in disarming avoidable ones.

So basically the idea is that monsters are generally dumb or overconfident in their abilities to avoid a trap. Can this be manipulated for player benefit? Yes. But I think it's actually a fun way of manipulating monsters.

Of course we need to figure out how to deal with a stat-drain dart hitting a monster. Or even more confusing, one that steps on a summoning square.

[Old Coach]

With the ideas put forth so far, there are just awesome things that can be implemented to enrich the game. Everything from Varyo placing fire turrets to the elemental themed vaults.

The vault with air, fire, earth, and water turrets in opposite corners (or wings), maybe with their appropriate monsters, with halls that spiral or lead into the central room with the chromatic turret that fires off something attention grabbing like power dragon breath. Only rogues need apply to this vault...

And let us not forget about the monster turret - that shoots (summons) a monster every few turns once activated (by stepping into the room or inspecting a chest). Of course, I like the idea of it shooting snaga at the @'s head for damage equal to the hapless goblin's health, but I have strange idiosyncrasies like that.

I am getting giddy with the coolness that an updated trap system can bring!

[CunningGabe]

The basic functionality is mostly done; I should have something playtestable in a day or two. I'll post here once I make the pull request to summarize what is included and what I still plan to do (which is quite a lot).

[CunningGabe]

The new trap code is now in v4! Here is a summary of the changes so far:

Changes:
1. Detection
	a. All characters have a detection radius of 1, or 2 when they search.
	b. Secret doors are always detected when they are within detection radius.
	c. Some races/classes have had their search skill changed, and WIS/INT both contribute to search skill.
	d. Mimics and Lurkers are detected if search skill surpasses 45 + DL/2.
	e. Traps are detected if search skill surpasses their hiddenness rating, which is approximately 35 + DL/2 +/- 5 for an average trap.
	f. Trap detection spells haven't been changed yet, nor has the DTrap border.
2. Evasion
	a. It is now possible to evade a trap if your DEX is high enough.
3. Trap types
	a. Traps now enforce a min level and a max level.
	b. Many traps have been split into multiple types, with deeper traps being more dangerous.
	c. Chest traps are completely gone.
4. Under the hood
	a. Traps have been removed from terrain.txt, and a new trap layer has been created.
	b. Some small amount of work has been done to make use of the terrain flags, and unhardcode terrain types. 
	(For example, try adding PWALK to the granite walls, and then walk right through them!)

I would encourage you to try to play without using trap detection. I haven't decided yet how I will deal with that exactly, but for the moment, I think the game is playable without it.

There are currently not very many kinds of "deep" traps -- only 3 kinds are possible after DL50. Fixing this is one of my first priorities, and I will be drawing from the trap brainstorming thread. You can add your own traps if you want them to use an effect that already exists.

I am also planning to work on the other 2 mechanical aspects of traps -- disarming and evasion. Eventually, a trap will have a rating for how hidden it is, how hard it is to disarm, and how hard it is to avoid setting it off. One of the thoughts I've had is that magical traps, like teleportation and summoning, could possibly be made so that they cannot be disarmed except by magical means. So you either avoid them completely, or try to tiptoe on to them and evade the trap.

Any comments, bug reports, etc. are welcome!

[Derakon]

Neat! I should probably fire up v4 one of these days and get some actual playing in...