Cancelling dash momentum facing forward when falling

[magicsixball]

It's hard to title this one...

So this happened recently and I wanted to get to the bottom of it. S2J dashes off stage and holds backwards expecting the usual forward momentum, but it wasn't there. It's happened to me plenty of times, usually when going for drop zones, and can throw off your spacing if you aren't expecting it. This was an unfortunate example as S2J dies from a shine after the sequence above.

If you're familiar with pivot dropping (don't know if that's the actual name for it), or turning before falling from the edge, you've seen this kind of momentum cancelling before. However, what's interesting here is that falcon never turns around and continues to face forwards.

Here's what I came up with: To understand what happened, we have to look at falcon's environmental collision box, or his ECB. When falcon dashes, his ECB widens, keeping him onstage longer. The frame after you input a turn, his ECB tightens, and if the new ECB is offstage, the game puts him offstage without ever giving him a chance to turn. This keeps him from turning around while still canceling his forward momentum.

Above is a screenshot of falcon 1 frame after inputting a turn from on stage. The old ECB shows his dash ECB, and the new ECB shows his turn ECB. Because his turn ECB puts him offstage, falcon never enters his turn animation. You can't really do this consistently, however, since some frames of his dash won't make his ECB wide enough to put his turn ECB offstage.​

If falcon enters his turn animation at all (AKA if his turn ECB does not put him offstage), he will be facing inwards when he falls and will grab ledge (if he doesn't do anything else). It doesn't matter if he turns for 1 frame, 2 frames, 3 frames, etc. If his dash momentum causes him to slide off after entering turn, he will be facing inwards.​

Not all characters are able to do this, and if they can it won't happen very often. It may be a freak of nature that falcon is able to do it at all. From what I can tell, it depends on 3 things: how fast a character's dash speed is, how wide their dash ECB is, and how wide their turn ECB is. If it's ever happened to your character, let me know.​

Edit: Thanks to Sycorax for debunking my original theory! Turns out it's the marginal shift of your base position from your dash that puts you offstage in 1 frame after turn.

The only part of the ECB that controls whether your on stage is the bottom of the diamond (which is linked to a character's base position. It cannot shift horizontally without causing character movement)

Awesome, didn't know that! Hmm, so you're saying there is no transition between action states that shifts your base position. That makes sense.

So it really is a pivot on the last frame you're on stage, but it's not common. In my tests, i think like 2/3 last-frame pivots had at least 1 frame of Turn on stage. So your last frame of dash must be really close to the edge for the momentum to put you offstage in 1 frame.

 

[iAmMatt]

This is an interesting thread. Correct me if I'm wrong, but the same sort of momentum cancel would occur if you slide off the stage during jumpsquat and immediately hold the control stick in.

If you're familiar with pivot dropping

Also I think you're talking about pc dropping

 

[Sycorax]

magicsixball
Cool stuff, but I think your explanation is slightly off. The only part of the ECB that controls whether your on stage is the bottom of the diamond (which is linked to a character's base position. It cannot shift horizontally without causing character movement). If that point is no longer touching the floor, then your character has moved off the stage and is under the effects of gravity. The width of the ECB doesn't matter because what controls whether you're on stage or not is a single point at the bottom of the ECB.

I am pretty sure what is actually going on is the following. Pivoting doesn't stop your momentum instantly. You have a small forward velocity during Turn that quickly diminishes. In this clip, S2J pivots, but the speed on the first frame of the pivot is enough to push him over the edge. So his last frame on stage, he inputs a smash backwards. The next frame is calculated. The game stops almost all of his momentum (because he is pivoting) and updates his position. When his position is updated, he ends up off the stage. You can't be in Turn off stage so he is put in Fall, but with no momentum. And since he never entered a single frame of Turn, he is never turned around to facet he other way.

So it really has nothing to do with his ECB, just his base position (which his ECB is attached to when grounded).

This is an interesting thread. Correct me if I'm wrong, but the same sort of momentum cancel would occur if you slide off the stage during jumpsquat and immediately hold the control stick in.

Not really. When you jump, friction starts applying which slows you down before you cross over the ledge. That ends up not being that relevant here anyway because when you pass over a ledge and you are moving faster than your max air speed, you are instantly slowed to your max air speed (see Luigi WDing off a platform). Falcon's run speed is 2.3 and his max air speed is 1.12 so he slowed down considerably when he runs over the ledge. And jumping before doing it will not give friction enough time to get your speed below 1.12.

 

[magicsixball]

The only part of the ECB that controls whether your on stage is the bottom of the diamond (which is linked to a character's base position. It cannot shift horizontally without causing character movement)

Awesome, didn't know that! Hmm, so you're saying there is no transition between action states that shifts your base position. That makes sense.

So it really is a pivot on the last frame you're on stage, but it's not common. In my tests, i think like 2/3 last-frame pivots had at least 1 frame of Turn on stage. So your last frame of dash must be really close to the edge for the momentum to put you offstage in 1 frame.

Also I think you're talking about pc dropping

PC dropping is out of a walk, I'm talking about out of a dash (where you smash turn, not tilt turn)

 

[Sycorax]

so you're saying there is no transition between action states that shifts your base position

Not exactly? I'm not sure what you mean exactly, but one has to be very careful with the way they word these things. Shifts to your base position do occur during and between action states, but all such shifts are equivalent to movement. I emphasize this because, for example, people misunderstand how edge canceling works and think using aerials will shift their ECB to better slide off the edge, which is not true.

 

[magicsixball]

Not exactly? I'm not sure what you mean exactly, but one has to be very careful with the way they word these things. Shifts to your base position do occur during and between action states, but all such shifts are equivalent to movement. I emphasize this because, for example, people misunderstand how edge canceling works and think using aerials will shift their ECB to better slide off the edge, which is not true.

I got what you meant, I wanted to say like no tilts for example would change your base position from stand to tilt, only movement like dash or walk can change your base position. Thanks for clarifying though!

 

[Cressel]

So a last frame pivot makes him fall off momentum-less without turning around then? That's pretty interesting. I'm assuming this Captain Falcon exclusive, I don't think I've ever seen it happen before. Besides I can't think of much to give it use.

 

[Sycorax]

So a last frame pivot makes him fall off momentum-less without turning around then? That's pretty interesting. I'm assuming this Captain Falcon exclusive, I don't think I've ever seen it happen before. Besides I can't think of much to give it use.

It can happen with any character.