Trajectories for a biped in cycle mode

pixeldamage

Anyone know how I can switch on trajectory lines for a biped in cycle mode (In Place Y mode)? I've searched everywhere man and I can't find out how to get around the fact the object properties > trajectories is greyed out. Note: the trajectory button on the display tab doesn't work in the same way.


After watching a cgchannel video on the male walk cycle I found this problem which has got me proper stumped. The teacher mentions using Object Properties>Trajectories on the foot of the Biped but this doesn’t work in max2k9 as trajectories in the general tab is greyed out when using bipeds. I googled it and apparently they took out this functionality after max6 (which the mentor is using).

They mention the issue here http://area.autodesk.com/index.php/forums/viewthread/3808/

Mark Dygert

Biped has its own trajectories toggle.

It's in the biped menu under, Modes and Display > Display > 2nd to the last icon, looks like a squiggly line.

What he is talking about in that post was turning on trajectories for the dummy helpers that act as terminators at the end of the links. The biped trajectories toggle works fine on normal biped pieces, I'm not really sure why someone would want to display trajectories of the helpers...

pixeldamage

Vig wrote: »

Biped has its own trajectories toggle.

It's in the biped menu under, Modes and Display > Display > 2nd to the last icon, looks like a squiggly line.

Thanks for your reply, but I mentioned already that one doesnt work properly when the cycle "in place" button is in use. In the tut video (not online unfortunately) he shows the difference but that was in max 6

Mark Dygert

It would be helpful to know what the difference is?
How is it broken and what is it you want it to do differently?

When I turn it on and put a biped in in-place mode, it behaves like it always has.

pixeldamage

Sure Vig, that's why its annoying the video isn't online. My best description is that the one you mention gives an innacurate trajectory display when the biped is in "IN PLACE Y MODE". With the foot selected, I get a wiggly line along the ground that disappears when the foot slips back again. In the video, using the other trajectory toggle, there's a nice circular trajectory (I guess as it doesn't get confused when the foot comes back). The reason I wanted to find this one is that the tutor shows how you can shape the trajectory and smoothen out the kinks to make a nice cycle, IE if you have a nice circular trajectory you get a nice smooth animation.

Mark Dygert

OOoooo I think I know what is going on. Was your Biped originally moving forward, like you used footsteps to animate a walk cycle but need the biped to stay in place?

In place mode is a way to treat a character like they are moving forward but without them actually moving. Think of in place mode as a way to move the world around the character while its on. It was meant more as a temporary state you use to work on the character. So lets say you have a character running all over your scene like a wild kindergartner, you want to work on the contact points but don't want to move the viewport all over the place chasing the character down. So you put it in in-place mode work on the contacts, and then take it out of in place mode to get it moving again.

In-place mode does get used for games quite a bit but it does give you linear tragectories and not circular, making somethings difficult.

To get circular trajectories like you want I suggest you zero out the X position, killing its forward movement.
You do this by clicking on the COM, opening workbench and changing the top drop down menu from Rot Curve to Pos Curve. Set the filter to show X only. Then select all of the blue (x axis) points and delete them. This will still give you a nice up and down motion but now it won't actually move forward and back.

Mark Dygert

There is one more thing that could cause a snag and that is planted keys if you had any. You'll want to copy paste the pose on each frame, and turn the planted keys into free keys. Then you can zero out the X position.

You can also save out a few frames of the biped in the position you want, and save out the newly freed walk cycle before delete the X position keys, then load both clips into motion mixer on their own track group, and filter out everything but the COM forward/back on the position track, and reverse that on the walk cycle. Compute the mix and copy it to biped.

pixeldamage

Vig. Yeah I think you nailed it. I was doing exactly as you said, movement and then using In-Place to make the walk static. I understand why the trajectories were messing up; it was my first thought when i saw the dodgy trajectories. The thing is, the Object Properties window toggle for trajectories actually used to work with In-Place mode (even when the cycle was made using X-axis animation) but for some reason it doesn't after max6. I will definately try out your ideas, though i've got around the problem by eye-balling it and using the track view window curves as reference to smoothness. I have used a lot of planted keys as that's what seems to be recommended for each key where the foot touches the ground - so it seems i will have my work cut out. Not heard of workbench yet, this is my first venture into animation after several years of modelling/texturing/rendering.