Link Mocap walk cycle to a path?

[Morne]

Hi all

It's been a while since I last did this. So, I have some mocap of a walk cycle that I added to my bibep. How can I use that walk cycle to make my biped walk on a spline path?
If it's easier with CAT, then by all means let me know the "steps" with that instead (hehehe, steps)

[joconnell]

Biped is really really old so it doesn't have this at all. What I did when I was doing digital doubles on a few things was counter animate the character so that it walked on the stop, cached this walk on the spot to a point cache file and then measured how far the planted foot travelled and over how many frames. Say you're animating at 24fps, most people take two steps a second so it'll take roughly 12 frames for the planted foot to slide backwards. If it moves 1 metre in scene units over the course of 12 frames, then your biped probably moves at 2 metres every 24 frames or one second. If you've a spline that's 20 metres long, you divide the length of the spline by how long each left / right pace is so you end up with 20 metres divided by 2 metres every second and get ten seconds total to walk the length of the path. So you set one keyframe at the start of the path at frame 0, and then have a second keyframe at the end of the path ten seconds worth of frames later.

[AlexP]

Surely there is an automated way to do all that though?

[Morne]

Biped is really really old so it doesn't have this at all. What I did when I was doing digital doubles on a few things was counter animate the character so that it walked on the stop, cached this walk on the spot to a point cache file and then measured how far the planted foot travelled and over how many frames. Say you're animating at 24fps, most people take two steps a second so it'll take roughly 12 frames for the planted foot to slide backwards. If it moves 1 metre in scene units over the course of 12 frames, then your biped probably moves at 2 metres every 24 frames or one second. If you've a spline that's 20 metres long, you divide the length of the spline by how long each left / right pace is so you end up with 20 metres divided by 2 metres every second and get ten seconds total to walk the length of the path. So you set one keyframe at the start of the path at frame 0, and then have a second keyframe at the end of the path ten seconds worth of frames later.

Wow that sounds very impressive. It's probably more impressive if you speak Greek. So what would all that translate into english?
:- )

I'm happy to do this with CAT. It has the standard walk on the spot thing. I can probably figure out how to load the mocap files. For the rest I understand WHAT to do, I just need to know HOW to do it
:- )

[Morne]

Surely there is an automated way to do all that though?

Jip, you would think. I feel like I just woke up and it's the dark ages

[joconnell]

Surely there is an automated way to do all that though?

I did a script for it but you've got to work out the pace distance yourself

[Morne]

I did a script for it but you've got to work out the pace distance yourself

Sounds awesome. Would you mind sharing the script pretty please with some basic instruction on its use? I'm sure I can work out the pace distance, my calculator has some funny buttons for this - sin cos tan, sounds greek so I'm sure it will help
:- )

[Morne]

This looks interesting. Think I will try this in the meantime:
http://download.autodesk.com/esd/3ds...Number=d0e6680

Sounds almost like what John was saying

[AlexP]

I did a script for it but you've got to work out the pace distance yourself

Cool
Do find this sort of thing a bit frustrating with max. Any time ive just wanted to put some simple characters in, doing simple things like walking along a line it always turns into some epic mission. Seems like such a basic function that should be built in to the bipeds or whatever.

[Morne]

Whooohooooo this works NICE!
Thanks for stearing me in the right direction John!

So if others are interested you can replicate this like so:
Draw a spline with curves up and down or whatever path you want your dude/dudette to walk on
Measure the spline length with the measure utility in the utility panel.
With John's calculations, take the length of your spline (in meter) and divide by 2 and then multiply by 24 (24 frames a second) so you know how many frame it will take to walk the length of the spline
Create a dummy and path constrain it to the spline
Select your CAT object
In the globals panel for your cat rig (after adding motion layer) enter the number of frames you calculated earlier as "end"
Pick a node (the dummy) and tick "Walk on Path Node"

I'm sure you guys can figure out the rest

Will test a bit later if this also works with mocap

[YoyoBoy]

The CAT Motion Layer thing could be so great. The problem I've had with it is that the initial walk cycle that it gives you is pretty bad for most things. I can't tell you how many hours I've spent tweaking those curves just to try to get something that looks natural.

But here are a bunch of very good CAT video tutorials for you with really low audio: http://download.autodesk.com/us/3dsm...ies/index.html

[Morne]

Just when I thought I'm getting somewhere

What am I missing here. When I load some mocap for my CAT rig, it scales the while thing out of proportion. For example the torso and legs are suddenly 100 times longer, looks like an extreme giraffe. Same mocap file works fine on same size biped rig
Tried various combinations of mapping the bones, all result in same thing?

[Morne]

OK I'm going a bit back and forth here...
Seems I will end up using biped for this since most of characters are already rigged and skinned with biped. I can't figure out how to make my biped walk with the dummy on the path.
I have the lenght of my path. I worked out how many steps the biped should take to walk the distance of the path and have just the right amount of frames. But then when I scrub the timeslider or play, the biped doesnt stay with the dummy, it walks away from the dummy?!?

I'm with AlexP on this one, how can something so simple not be built in, it's 2014 after all. Very frustrating

[joconnell]

Is the biped walking on the spot when he's not linked?

[Morne]

Is the biped walking on the spot when he's not linked?

No, I couldnt figure out how to do that. I tried then to counter the movement by adding a minus value to the distance between the footsteps to make the biped walk backwards to counter the movement from the dummy. That didnt work either