I’ve got a root motion montage of a jump that’s ending before touching the ground, that way I can extrapolate the current acceleration/gravity force extending the animation until the character touches the ground IE is jumping off a ledge higher than the current mocap animation.
Now, current acceleration is obviously: Accel = Delta Velocity / Delta Time
All I want to do is to set the initial impulse/gravity to that value so it will continue the motion seamlessly.
In order to do so I apply only once:
Character->AddImpulse(Accel)
Now, this is where the problem starts, it looks like the Acceleration vector is off by two orders of magnitudes, IE I need to multiply it by 100 in order to obtain a visually correct and seamless motion.
I’d say “visually” cos I’m not sure at all that how a random multiplication by 100 could make it right, unless my AddImpulse idea is flawed from the beginning…
(I thought maybe a strange meters/cm conversion for that 100 scale, because it just looks perfect so I’m quite puzzled).
Is that the right way to approach this problem (inserting gravity/acceleration into a character) or is there another way?
If I understand correctly you want to set your character velocity to a predetermined value on the Z axis(falling).
What I would do is get your current velocity: FVector CurrentVelocity = GetCharacterMovement()->Velocity;
And then set the Z value to your calculated falling velocity CurrentVelocity.Z = Accel;
Now you can apply this to your character movement like this: GetCharacterMovement()->Velocity = CurrentVelocity;
to ensure you only change the vertical velocity. You might have to do CurrentVelocity.Z += Accel;
if you want to add velocity and not completely calculate it yourself
I’ve tried to fiddle around with Velocity at first but it always creates a discontinuity, as you can’t add Acceleration value (m/s2) into a Velocity value (m/s), they are two different motions and curves.
I can’t see how gravity and acceleration are handled internally unless I want to go deep and study CharacterMovement class, which I think it’s what I have to do anyway hmmmm
I found something that looks to me as that you should use AddForce instead of AddImpulse.
Maybe I’m wrong, but it’s worth a shot as AddForce doesn’t adjust for fps, and you mentioned multiplying your value by 100 which would be close to the fps you are probably getting
Oh thanks a lot, that’s very interesting, it makes sense finally!
The key point there is that AddImpulse will add a ** 1-second worth** of impulse, while AddForce you’d need to call it for a duration and it’s per frame-based, but I can’t do that as I haven’t got a tick function for that!
