Please explain Jump-skill to me

[Jon_Dahl]

High jumping is about reaching a certain height.
Long jumping is about reaching a certain distance.
What if both are needed simultaneously? Let me give you an example:

Subject is standing in front of a log, which is 3 ft tall and effectively fills the whole 5*5 ft square. Subject needs to jump over the log to the other side. What is the DC and is this high jumping or long jumping? And what is the DC?

I'm thinking that by RAW this jump is impossible. Why?
You have to cover at least 5 ft of distance if you want to jump over the log. But since you only reach the required vertical height at the MIDPOINT of your jump, you can't jump over it if you're standing in front of the log. Therefore you have to have at least 6 ft of distance to the log.
Summa summarum: No character in the world (without magic) can jump a 3 ft log in from of him or her, without taking some distance first.

[DemonRoach]

By RAW, I think you'd be right.

This is one of many points where the DM makes a call, assigns an eyeballed Jump DC to get over the obstacles and the game continues. :smallsmile:

[candycorn]

From the SRD, Jump skill:
Hop Up
You can jump up onto an object as tall as your waist, such as a table or small boulder, with a DC 10 Jump check. Doing so counts as 10 feet of movement, so if your speed is 30 feet, you could move 20 feet, then hop up onto a counter. You do not need to get a running start to hop up, so the DC is not doubled if you do not get a running start.

DC 10 check, and then walk off.

[Seharvepernfan]

Also, when jumping distance, you jump vertically at 1/4 the distance. So, if you jump 40ft. out, you jump 10ft. up at the midpoint of your jump.

[Ashtagon]

RAW, it is impossible.

Common sense, you place one hand on the log, and jump with your body going lateral to the ground while using your hand for balance.

If you mean literally jumping over it though, nah.

[candycorn]

RAW, you jump up on the log, and walk off, and it's quite possible, as I outlined earlier.

If you're small size, you climb it.

[Ashtagon]

RAW, you jump up on the log, and walk off, and it's quite possible, as I outlined earlier.

If you're small size, you climb it.

Well yeah, there's that too. But literally jumping over the log, without touching it, is pretty much a superhuman task.

RAW, a long jump of 10 ft is DC 20 with a standing start, but only allows for a vertical clearance of 2.5 ft. We need a vertical clearance of 3+ ft, after travelling 2.5 ft horizontally (assuming you start from the centre of your space).

A 3 ft high jump from standing start is DC 24. Given that in a long jump you move vertically 1/4 the horizontal distance, I'm quite happy to allow high jumpers to move horizontally up to 4x the vertical distance jumped.

So, DC 10 if you hop up then step down. DC 24 if you want to literally jump over it.

[candycorn]

Which makes sense, since hopping up and jumping down uses 15 feet of movement, and jumping over uses 10.

Note, however, without a running start, that 3 foot jump DC is doubled, meaning a daunting 48 DC.

[Ashtagon]

Which makes sense, since hopping up and jumping down uses 15 feet of movement, and jumping over uses 10.

Note, however, without a running start, that 3 foot jump DC is doubled, meaning a daunting 48 DC.

Actually, I had already doubled the DCs to account for that.

[Chronos]

Note also that, by RAW, you get just as high on a long jump as on a high jump, anyway.

[Mystify]

Note that jump doesn't account for lifting your legs. You don't need 3 feet of jump to get over a 3 foot obstacle. It measures how much distance your head gains, and by extension the top of your reach.
"A high jump is a vertical leap made to reach a ledge high above or to grasp something overhead." i.e. the rules are not talking about jumping over an object at all. Hence, you must account for lifting your legs yourself.
By strict RAW, you can't jump over anything, period, because it doesn't talk about jumping over objects.

[Hiro Protagonest]

Well, let's see what the rules say...

Long Jump
A long jump is a horizontal jump, made across a gap like a chasm or stream. At the midpoint of the jump, you attain a vertical height equal to one-quarter of the horizontal distance. The DC for the jump is equal to the distance jumped (in feet).

[Dr_S]

Well, let's see what the rules say...

aha, but you have to reach a height of 3 feet and maintain it for 5 feet, you'd need to have travelled 6 feet before reaching the object, 6 feet after and 5 feet to clear the object. A Long jump distance of at least 21 feet.

because if you reach a quarter of the total distance during the entire jump then at the mid point you've traveled half the distance total but the max height, so half as high as you've risen, which means that we can estimate (though I realize this doesn't work in real life but since the mechanics are explained linearly, the calculations should be done so as well) So if one were to jump 12 feet with the mid point over the object, when they reached the object they'd have traveled 3.5 feet forward and have likely only risen 1.75 feet, slamming their shins into the side of the object and then face planting so hard.

In real life hopping over an object like that, no running start would be a nigh superhuman feat. (not the 3' tall bit but maintaining that jump for 5') so I'd suggest either trying to meld the high jump and long jump rules or house rule something based on the 21 foot jump. It seems either way you do it, the DC should be over 21 at a very minimum.

Though if you're asking just how to move over it, use the DC 10 climb and move off it method.

[Mystify]

aha, but you have to reach a height of 3 feet and maintain it for 5 feet, you'd need to have travelled 6 feet before reaching the object, 6 feet after and 5 feet to clear the object. A Long jump distance of at least 21 feet.

because if you reach a quarter of the total distance during the entire jump then at the mid point you've traveled half the distance total but the max height, so half as high as you've risen, which means that we can estimate (though I realize this doesn't work in real life but since the mechanics are explained linearly, the calculations should be done so as well) So if one were to jump 12 feet with the mid point over the object, when they reached the object they'd have traveled 3.5 feet forward and have likely only risen 1.75 feet, slamming their shins into the side of the object and then face planting so hard.

In real life hopping over an object like that, no running start would be a nigh superhuman feat. (not the 3' tall bit but maintaining that jump for 5') so I'd suggest either trying to meld the high jump and long jump rules or house rule something based on the 21 foot jump. It seems either way you do it, the DC should be over 21 at a very minimum.

Though if you're asking just how to move over it, use the DC 10 climb and move off it method.
Again, the rules are not designed for jumping over an object. What you are trying to do with th RAW is hop over the stump with your legs sticking straight down. The rules are designing for jumping up and reaching things above you. There is literally nothing in the RAW about jumping over objects.

[ericgrau]

Also, when jumping distance, you jump vertically at 1/4 the distance. So, if you jump 40ft. out, you jump 10ft. up at the midpoint of your jump.
This is RAW too. That's how you do it. If the log is 3 feet high it's a DC 12 to clear it both vertically and horizontally, or twice that without a running start.

It's also true that hopping up on top of the log instead of clearing it is a little easier.


There is literally nothing in the RAW about jumping over objects.
Except this:


Long Jump
A long jump is a horizontal jump, made across a gap like a chasm or stream. At the midpoint of the jump, you attain a vertical height equal to one-quarter of the horizontal distance. The DC for the jump is equal to the distance jumped (in feet).


There's also no need to complicate with further details for a round log. You only need to worry about the high point of the log. Simply put the curve of the log is sharper than the curve of the jump, so at all points besides the high point you have even more clearance than the high point and your'e totally fine. A flat-topped object would be a little more complicated, but a RAW jumping curve is so shallow you'd only need to jump a small amount higher at the peak to also clear the corner.

[Ashtagon]

hmm, ok, so I didn't account for the fact that the log is 3 ft at every point.

So you need to maintain a height of 3 ft over at least 5 ft. That means that at the midpoint, you need to achieve a height of 4.875 ft, which is equivalent to a long jump of 19 ft. This is DC 19, or DC 38 from a standing start.

If playing by 3.0e or d20 Modern rules, add +5 and +10 to the running and standing start DCs respectively.

[Acanous]

IRL if something was 5 feet tall and 5 feet across (Like say, a small car) it would be extremely difficult to jump over (There are athletes that can do this, but not many).
eyeballing the thread, that DC24 check looks the most accurate, aside from the DC10 hop, which is also accurate.

[Dr_S]

Again, the rules are not designed for jumping over an object. What you are trying to do with th RAW is hop over the stump with your legs sticking straight down. The rules are designing for jumping up and reaching things above you. There is literally nothing in the RAW about jumping over objects.

I was using the height achieved during a LONG jump as quoted already in the post I was quoting, but since this forum doesn't allow for quote-ception, it got removed from the bit I quoted. It would be irrational to apply the same "reaching" rules to long jump and high jump, that line was clearly added to the long jump for clearance purposes as it's no one long jumps with their feet straight down. (low ceilings, or jumping over obstacles)



There's also no need to complicate with further details for a round log. You only need to worry about the high point of the log. Simply put the curve of the log is sharper than the curve of the jump, so at all points besides the high point you have even more clearance than the high point and your'e totally fine. A flat-topped object would be a little more complicated, but a RAW jumping curve is so shallow you'd only need to jump a small amount higher at the peak to also clear the corner.

The OP uses the same 6' estimate I did in his last sentence, which suggests that this jump is perhaps along the length of the log (i.e. in a 2D plane showing our jump it would not have any noticeable curve)

You could use advanced maths like Ashtagon and save yourself 2 feet however you're not going to end up saving yourself that much on the DC and linear estimations are a lot quicker to do at the table (not to mention that we calculate movement through diagonals as an extra square every other move... so making accurate real life trig calculations might not be consistent)

So imo, 4h+d = the distance of a long jump required to clear an object where h is the height and d is the distance for which that height must be maintained.

OP you're right that without the extra distance you'd be SOL by RAW because they do not describe clearing an object without having tons of room. If I were DMing though, I would say, add 1 to the DC for every foot the jumper wants to make the jump shorter. (and that the distance shortened must be evenly split between both sides)