Acrobatics - tic tac - underwhelming

[BraselC5048]

Running the math for a tic tac (Martial Arts), it just seems, well, lackluster. The height limit is low, but not too bad. The problem is the very narrow space required to do it. I have a character with Basic Move 10, and even she can't do it on anything more than 5' apart. Even worse for more normal characters. I fail to see much benefit from doing it when the walls are just 3 feet apart - you can climb that even if it's perfectly smooth by bracing between them.

Scaling from some Tomb Raider screenshots, which is more along the lines of what I, and I suspect most people, think of as what a high power acrobatic character can do, it's seems she can do it from a standing start (possibly with extra effort) between two surfaces 8 feet apart, possibly as much as 10 feet, but I'll stick with 8. Estimating her stats at around DX 15, HT 12, something like that, I would assume she has Basic Move 8. Which is the same distance in feet as how far apart she can do it.

She seems to have a maximum elevation gain of about 20 feet. Which is 2.5 times her Basic Speed. Elevation gain each bounce seems to be about 5 feet, or a quarter of that.

Which would seem to pretty much write itself rules-wise as Basic Move feet apart, (adding running start to Basic Move on the ground level), 5/8th Basic Move of height in feet gained each time, and a maximum height gain of 2.5x Basic Move feet.

Seems more like what a high-powered Basic Speed 8 could do. Any thoughts?

Also, would extra effort increase the height limit, or not?

[Anthony]

Super Jump, perhaps?

[Xaviien]

I would think the height you could gain might also be limited by the distance between the walls.
There are not as many videos of people doing this as I would have expected though.
http://m.youtube.com/watch?v=we8WuOC1yUE

[Flyndaran]

Originally Posted by Xaviien

I would think the height you could gain might also be limited by the distance between the walls.
There are not as many videos of people doing this as I would have expected though.
http://m.youtube.com/watch?v=we8WuOC1yUE

I imagine it's like jump kicks. They look awesome but are at best risky and almost always near useless in real life.

The rules involve distance between walls as it is.

[Mailanka]

I understood the point of tic-tacs as speed, not height. You don't try to tic-tac up a mountain, you climb it. But if you need to get over the top of a fence at the end of a narrow alleyway during a foot-chase, then a tic-tac is in order.

[BraselC5048]

This video (20 seconds in) and this screenshot (more accurate distance, although I can't find the ones I scaled it from) shows what I'm thinking about as what most people think of it. It just seems that even with extreme basic move (move 8 is gold medal winning olympic gymnast IMHO), not being able to do it between walls you can't touch at the same times just seems wrong. Heck, not even basic move 10 being able to do it seems wrong. It just seems like basic move feet like I posted above would model high-power characters better.

Originally Posted by Xaviien

I would think the height you could gain might also be limited by the distance between the walls.
There are not as many videos of people doing this as I would have expected though.
http://m.youtube.com/watch?v=we8WuOC1yUE

That video is pretty much the strongest argument possible against RAW. Your video scales to about 8.5 feet width, and about 3 feet elevation gain each time. I don't think he's basic move 15, which is what RAW would require for that. Going by what I came up with, and using my horizontal versus vertical jumping distance graph I made, trading height each time for distance (6.75 feet long and 4.25 feet up to 8.5 feet long and 3 feet up) results in him being basic move 6.75, which actually sounds about right. The shaded black bar in this picture is the maximium RAW allows. I was planning to photoshop the width between the walls down, but he's already taking up more space then the maximum GURPS would allow! ! Considering he doesn't even fit within the bar while doing it, I suspect it might not be possible to do it in a width that narrow. I think it's pretty likely that RAW grossly underestimates both borderline cinematic reality and real life.

[BraselC5048]

Originally Posted by Ransom

Those Tomb Raider videos look to me less like tic tacs and more like repeated jumping and grabbing. I think the problem might not be that raw doesn't allow high-skill characters to emulate Laura Croft, but that you're trying to use the wrong mechanics to do so.

No, it's definitely a tic tac, the video even says they're doing a chimney jump (the same thing) with at least 4 bounces to get an achievement. Also, I've watched complete playthroughs of that game, and jumping and grabbing looks very different. And requires in that game a rather (for practical gameplay reasons) visible ledge to grab onto, which from the same level looks like this (red arrows), not there in the video. The reason it looks like that is that doing it in the game requires you to hit a button to shove off, and the pause is simply there to give the player time to hit it - it's a necessary for how the gameplay mechanic works. The shove off isn't automatic, and the player has to be given enough time to see the character in that position to recognize the position and timing and do it. It's also worth pointing out that the distance in the game is about the same distance as the real life video Xaviien posted.

Definitely a tic tac in the game, and I even somewhat surprised myself how closely it seems to model the video you posted. Seems to pass the real life test, and also gives the results you expect for high powered acrobatic characters.

[Bruno]

Originally Posted by BraselC5048

That video is pretty much the strongest argument possible against RAW. Your video scales to about 8.5 feet width, and about 3 feet elevation gain each time.

I think your problem is how you're measuring distance, because those numbers seem... absurd?

The stairwell is 18 bricks wide, you can see them in the foreground. One standard brick is 3 5/8" wide, plus about 1/6" mortar per brick, gives a width of 68 1/4" or 5.6875 feet, which is around the standard width of a sidewalk. Proportionately to the parkourist, the stairwell visually checks out as about the width of a sidewalk, not the width of a sidewalk plus 50%ish.

His first kickoff is 13 bricks off the ground, 13 times 2 1/4" height (standard brick) plus about 1/6" mortar per brick = 21 2/3" height, a pretty reasonable jump height.

His second kickoff is 19 bricks off the ground, 45.9"

He hits the destination wall with his toes 18 bricks off the ground and is clearly loosing jumping height, but he can grab the top and clambers over.


EDIT: You might be having problems with the extreme fisheye effect caused by the very short lens on cellphones and the nearly-on-the-ground camera angle causing some really severe foreshortening. Combine that with the parkourist travelling into the background and things get pretty distorted.

[BraselC5048]

Originally Posted by Bruno

I think your problem is how you're measuring distance, because those numbers seem... absurd?

The stairwell is 18 bricks wide, you can see them in the foreground. One standard brick is 3 5/8" wide, plus about 1/6" mortar per brick, gives a width of 68 1/4" or 5.6875 feet, which is around the standard width of a sidewalk. Proportionately to the parkourist, the stairwell visually checks out as about the width of a sidewalk, not the width of a sidewalk plus 50%ish.

His first kickoff is 13 bricks off the ground, 13 times 2 1/4" height (standard brick) plus about 1/6" mortar per brick = 21 2/3" height, a pretty reasonable jump height.

His second kickoff is 19 bricks off the ground, 45.9"

He hits the destination wall with his toes 18 bricks off the ground and is clearly loosing jumping height, but he can grab the top and clambers over.


EDIT: You might be having problems with the extreme fisheye effect caused by the very short lens on cellphones and the nearly-on-the-ground camera angle causing some really severe foreshortening. Combine that with the parkourist travelling into the background and things get pretty distorted.

The biggest way it could be off is if the video is stretched in one dimension or another. I count 10 bricks high as being the same measurement on the screenshot on both sides. His apparent height seems to remain within about 10% from the first kick off to when he grabs the wall, so there doesn't seem to be any significant height distortion. There is a fisheye effect for distance, but I measured his height at the point he was doing the kick off, not while running up. Like I said, it's within 10% or so, and it seems (depth being very hard to measure here) no more than a foot and a half deeper into the picture than the first kickoff, so it seems that there's no significant height compression. I concur with the 13 and 19 bricks measurement, and the ratio between the number of bricks and measurements on the picture is within 10%, again. His first kick off was above the level of the railing, it would have to be (legally, in the states) about 30" off the ground, and he hit 3 bricks higher than that. Which comes out to a rather major difference, but none of us have any real idea how high the railing is.

I still get his own height on the second shove off, which is 6ft, assuming that's his height, and there seems to be no way around that. His apparent height is the same before, during and after that point, so there's not a lot of room for variation. I measured width scaling from his height (to the point of the first kickoff on the left wall, that's required to get the distance right) as 8.25 feet, and there seems to be no way around that.

Running it past the smell test, I find it highly unlikely that a large, curved stairway like that would be standard sidewalk width. Nearly all my experience and judgement would make it a couple of feet wider.

Considering he fails to gain height on the second bounce, but also stays about the same height, it's hard to figure out what exactly it represents in GURPS. A full 7 yard running start gets him the correct height on the second bounce, but still 2 feet short horizontally. The question is what to consider the second bounce. He goes the full distance, but fails to gain height, but the way the description in Martial Arts is written, he could still do that although failing to reach the opposite wall. Although I don't quite get how the heck you can fail to reach the far wall and still hang from it at the same height you started.

So considering what I've learned here, and fixing a very open flaw in the initial draft, here's the revised draft of my rules, actually closer to the mechanics from RAW that the first draft:

Improved draft of the rules - your horizontal distance is half your jumping distance, standing plus any running start or distance since the previous bounce, and minus a foot at the end, and your vertical distance is your high jump distance, standing plus any running start or distance since previous bounce. That would get sustainable distance back to about right, and let the guy (assuming Basic Move 6) in the video's 9.5 foot long (on first bounce with running start) and 62 inch high bounce trade distance for height for a 8.25 foot long and 72 inch high jump. (I need to do a spreadsheet making distance/height easier.) The second bounce is about a foot short on the far wall ((Basic Move 6 +2.5 yard start) x 2, -3 is 14, halved for 7, then -1 foot for 6 feet, or two feet or a little more feet short), but close enough to grab the top and maintain height (after grabbing). Your maximum height is still Basic Move x 2.5 feet.

From the "high powered acrobatic character" (move 8) above, that would be a 13.5 ft long and 7ft high initial bounce (although at no point does she get anything like that much), although the maximum for more than one bounce is about 8.5 feet long and 56 inches up. The long distance for a running start seems long, but it's only 1.5 feet more than her standing long jump anyway. anyway. Considering the scaling from the picture above could easily be 9-10 ft if measured differently (my method underestimated distance), and 56" is pretty darned within the margin of error for 5 feet, that doesn't seem to bad. Maximum height still fits, as it did from the beginning.

That seems to be the final draft, fits everything well (enough), matches what feels right for both Move 6 and 8, and considering that in real life height and distance are a tradeoff, more or less passes the reality check to within GURPS resolution.

[Celjabba]

Looking at the video, I count 19 pavements for the width of the stairs. Thats 209 cm at a standart width of 11 cm+ joints: 230 cm at most, 7ft 6 in. Possibly less if the pavement is thinner (10.5 cm or 10 are not uncommon), no more given the relative size of the foot over the pavement imho.

Celjabba