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CharonsHelper
2020-07-10, 05:18 PM
I'm currently finishing up my RPG, Space Dogs: A Swashbuckling Space Western

One thing that I'm having trouble on, is the geometry of cover. I know how D&D and it's offshoots do it, but I was hoping for something a bit simpler to keep combat streamlined, as cover is a major part of firefights in Space Dogs. It gives a large penalty to attack (-8 penalty when attacks are generally 2d10 or 3d6 - vary by weapon), and a good bit of the tactics is how to push foes out of cover with grenades etc.

It all works fine in playtests, but it's the edge cases which are tricky. At present there is cover and partial cover as shown here: https://ibb.co/6m7sty9 - shown with 3 iconics facing off against a razorback

Yuji (the guy with the assault rifle & katana) has the cover penalty, Ekon (guy with revolver) has a partial cover penalty, and Princess (girl with rocket launcher) has no penalty.

(And yes - I do own all of that artwork.)

My current rule is that you start from the nearest corner to the foe (you get to pick if equal), and if it goes mostly through the cover then they have cover, if it's half or less then they have partial cover.

Does this seem to work? Is there a better/simpler mechanic that you've seen to figure it out, or one that you've thought of? I try to stick to the KISS rule in game design whenever possible.

Mastikator
2020-07-11, 04:20 AM
To make the question harder, what if the cover doesn't reach up all the way to their head?

I think the most practical rule is that the DM simply decides, or that taking cover is an active choice by the one in cover, they crouch or bend or whatever to give themselves the cover they need and they can maybe only do it from one angle?

Silly Name
2020-07-11, 07:26 AM
If I was playing Ekon, I'd feel a bit shafted because the map actually seems to show Ekon having a clear line of sight against the monster. The box, at most, would cover a small part of its lower body, not enough to seriously impair Ekon's ability to take aim.

Your system isn't bad, but looking at this case I would be tempted to say that if the "cover" provided is less than half a square's face, then the creature is not covered. If it is more than half it is partially covered, and completely obfuscating line of sight is total cover.

CharonsHelper
2020-07-11, 01:51 PM
To make the question harder, what if the cover doesn't reach up all the way to their head?

I think the most practical rule is that the DM simply decides, or that taking cover is an active choice by the one in cover, they crouch or bend or whatever to give themselves the cover they need and they can maybe only do it from one angle?

In this case, the crate is low cover, which has to reach approx your waist. Yuji can fire at the razorback, he just has the cover penalty to his ranged attack rolls, while Ekon has the lesser partial cover penalty.

If it was a wall, then Yuji couldn't fire at all.

I am considering just having the same cover penalty for everyone. It loses some tactical depth, but it'd be simpler.

icefractal
2020-07-11, 04:03 PM
Looks similar to the 3.5E D&D cover rules, except in those you get to pick which corner to use, so Yuji could draw from the NE corner and have partial cover (and that confusingly, a line tracing along a parallel wall counts as partial cover). I think it'd work fine, but IDK if it's as much more streamlined as you'd want - it still requires tracing 1-4 lines on a grid.

If you do decide to do just a single level of cover, you could go center to center. In this case that would be cover for Yuji, no cover for the other two. It reduces it to a single line to trace, and avoids questions about which corner to pick.

Pauly
2020-07-12, 09:33 AM
Wargames rules generally have moved away from different degrees of cover. Most rules now treat it as
invisible - cover - no cover
For extra differentiation cover can be hard cover or soft cover. Hard cover providing an extra or improved saving throw representing obstacles that will stop the attack. Soft cover just makes the target harder to hid representing things obstacles that block vision only.

Having played old school wargames that differentiated degrees of cover I found it slowed the game up and didn’t lead to better outcomes.

CharonsHelper
2020-07-12, 10:43 AM
Wargames rules generally have moved away from different degrees of cover. Most rules now treat it as
invisible - cover - no cover
For extra differentiation cover can be hard cover or soft cover. Hard cover providing an extra or improved saving throw representing obstacles that will stop the attack. Soft cover just makes the target harder to hid representing things obstacles that block vision only.

Having played old school wargames that differentiated degrees of cover I found it slowed the game up and didn’t lead to better outcomes.

Yeah, I'm now leaning towards a single level for cover for the sake of speeding up combat. That was really always my default, I was just seeing if I could make multiple levels work.

I am considering having an increased cover penalty if the target is adjacent to the cover - the idea being that they'll be up against it and actively using it for protection. I mean, being up against a big tree would be better protection than having a tree be halfway through the firing line.

Plus, it wouldn't lead to awkward situations where you use a grenade to push them away from cover, only for them to move backwards so that they crate/whatever is still between you and providing the same protection. And since there is no geometry involved, it shouldn't slow down gameplay.

Silly Name
2020-07-12, 10:56 AM
For my part, I'm not really opposed to having varying levels of cover, or having geometry involved - but I'm one of those guys who is endlessly seeking a balance between crunchy, tactical combat and keeping things fast and exciting, and I have learnt that it is a very fragile balance that is easily shattered if I get too involved in trying to create interesting tactical decisions.

There is always the option of presenting rules for more a complex cover system as "optional", with the default being the simple cover system.

CharonsHelper
2020-07-12, 11:20 AM
For my part, I'm not really opposed to having varying levels of cover, or having geometry involved - but I'm one of those guys who is endlessly seeking a balance between crunchy, tactical combat and keeping things fast and exciting, and I have learnt that it is a very fragile balance that is easily shattered if I get too involved in trying to create interesting tactical decisions.

There is always the option of presenting rules for more a complex cover system as "optional", with the default being the simple cover system.

I totally understand that. Over the several years that I've worked on Space Dogs, I have had several systems where I spent a long time coming up with an intricate system. And then when I look at it again a few weeks later, I grimace and strip it down to be more streamlined.

I do like to think that my system is better for it, as I think that said systems have more depth with the same complexity than if I'd just started with a simple system from the word go.

But yeah, I'm trying to make a system which is a mix of being both tactical and feeling fast/furious, which is a tightrope at times.

But anyway, considering how common cover is in Space Dogs relative to a D&D style system, I'm definitely leaning towards a single cover level, with maybe an extra level when the target is adjacent, since that's easy to figure out.

tyckspoon
2020-07-12, 11:48 AM
But yeah, I'm trying to make a system which is a mix of being both tactical and feeling fast/furious, which is a tightrope at times.

But anyway, considering how common cover is in Space Dogs relative to a D&D style system, I'm definitely leaning towards a single cover level, with maybe an extra level when the target is adjacent, since that's easy to figure out.

Well, the obvious solution here is for rocket-launcher girl to blow up the crate, thus damaging the enemy in the splash and obviating the problem for the other two >.> If they're really lucky the crate is also full of inexplicably explosive things.


I think what I would maybe go with is only one level of cover, but if the item you want to use for cover isn't large enough than you have to actively Go To Ground/Take Cover behind it. In this case, a waist-high barrier probably isn't really cover for the Razorback; your characters are going to be aiming for center mass unless there's some compelling reason not to (and if they're specifically aiming elsewhere that's what a called shot rule would be for), so any shots that would have hit the cover below the Razorback's waist can, in-fiction, be considered to just be misses anyways. Think of it like aiming for a target that is standing on top of a block versus one that's on a pole - although the block is easier to hit than the pole, in both cases it's just as easy to hit the actual target.

But the item is clearly large enough to provide significant obstruction, if you adjust your body to better make use of it - the Razorback has to actively kneel/crouch/squat behind it; he would take the Go To Ground action. He would now have the benefit of being in cover, but with hampered movement representing the awkwardness of exiting that position - can't charge/run out of that position, have to spend an action or use extra movement to leave cover, penalized melee attacks if somebody engages you while you're there.. whatever rules you've decided on to represent being Prone/knocked down can probably be reused here. You could also tie this into a more complicated determination of whether you're in cover, if you want - if you Go To Ground, then the defender gets the benefit of the doubt. If there is any line between attacker and defender that crosses the cover item, the defender is assumed to be doing their best to put it between them and the attacker, and they get the cover benefit. If they have not Gone To Ground, then if there is a line that does not cross the cover, the attacker can avoid the cover; in this case the defender is not giving their full attention to protecting themselves, and the attacker can find a chance to take the clean shot.

(And then there'd be Action Roll as a character skill/feat/perk/trait/whatever, which would allow the character to ignore the usual penalties/action costs for entering and leaving cover, for those guys with shotguns who somehow manage to carry out a running gunfight while rolling, diving, and crab-walking between cover, all without missing a beat in reloading, aiming, and shooting back.)

Nifft
2020-07-12, 03:48 PM
Geometry adjudication proposal:

1 - Attacker picks a point: any corner of his space, or the center of his space.

2 - If the attacker can find any line from that point ending at the center or any corner of the defender without touching cover, the attacker can make an attack.

3 - If the defender can find any line from that point to one of the defender's corners or center which does intersect cover, then the defender has cover.

You need to think in 3D to deal with low cover like in the picture, but the adjudication works as well on cubes as it does on squares, and the results might be forward-compatible with space-combat.

CharonsHelper
2020-07-12, 10:34 PM
Geometry adjudication proposal:

1 - Attacker picks a point: any corner of his space, or the center of his space.

2 - If the attacker can find any line from that point ending at the center or any corner of the defender without touching cover, the attacker can make an attack.

3 - If the defender can find any line from that point to one of the defender's corners or center which does intersect cover, then the defender has cover.

You need to think in 3D to deal with low cover like in the picture, but the adjudication works as well on cubes as it does on squares, and the results might be forward-compatible with space-combat.

I'm thinking that I'll stick with corners, as I don't believe that picking the center of the space would be beneficial to either side. But really, I think that I'm going to end up basically using largely the same geometry as d20 games, as the ways I've tried to tweak it end up being more confusing. Though I am going to go a bit more into 3-d aspects, such as firing over cover from the high-ground etc. But yeah, other than the corner thing - it's pretty much what you suggest in practice.

I guess that there are only so many ways that you can do geometry on a grid.

As for being compatible with starship combat - that's a non-issue in Space Dogs. The starship combat is intentionally very streamlined and abstract. I even have fluff for it being largely 2-d; because in-system starship propulsion is via gravity engines, which push/pull at large gravity wells such as stars and planets, so ships move much faster when they stay in the plane of the system. That, and I don't have to deal with momentum because the gravity engines can't keep pulling/pushing beyond a certain momentum, which happens pretty quickly. However, you can push it up a bit faster if you're following in the wake of another ship, making it so that combat does happen as opposed to being able to run away forever.

Finally, starship combat is designed so that the alpha tactic for the PCs is virtually always to board the enemy ship, bringing combat back to the infantry/mecha level ASAP.

Each space combat round is five minutes long, and since normal combat rounds are 3 seconds, there is enough time between rounds to board, do a lot of damage, and either take over the ship or get back to your own starship before their buddies can do much about it either.

Anyway - sorry for the ramble, but I'm pretty proud of how the starship combat integrates into the game. Most other sci-fi TTRPGs with much crunch that I've seen tend to have starship combat be a mess, or at least complex enough that the players & GM generally go out of their way to avoid it. (Note: I do still feel that way about my own vehicle system. Its usable - but nothing to write home about. I partially got around it by intentionally making vehicles sub-par in combat relative to mecha - whose rules I like a lot more - so there is little reason for combat vehicles to show up.)

kyoryu
2020-07-13, 09:49 AM
What I'd probably do here, with the assumption that all cover takes a full square...

Attacker picks a corner to shoot from.

If you are on-axis, you either have cover or not.

If you are off-axis, trace from your corner to the two far corners. If one is clear, you have half cover. If both are clear, it is a clear shot. If neither is clear, they have full cover.

For half-height obstacles, "full cover" becomes "half cover" and "half cover" becomes "quarter cover".

This is slightly permissive on the attacker's side (to get rid of arguments of "I COULD TOTALLY HIT THAT" and de-emphasizes one-block cover.