Creating a Distinctive Walk
Animating with Footsteps
Making a Biped Stop and Start Walking
Modifying Footsteps
In this lesson, you’ll learn how to copy and
paste biped footsteps to extend an animation. You'll also learn
how to adjust and bend the steps, and to produce the effect of walking
on uneven terrain. You'll also make the biped take a jump.
Set
up for this lesson:
- Continue
from the previous exercise, or open paste_footsteps_start.max.
Extend
the walk:
- Select
any part of the biped.
-
On the
Motion panel, in the Biped rollout, turn on Footstep Mode.
The Footsteps
sub-object level is activated, and only the footsteps can be selected.
- Right-click
to activate the Top viewport, then press Alt+W to maximize the viewport.
- Using
Select And Move, region-select footsteps 3 through 7.
-
On the
Footstep Operations rollout, click Copy Footsteps to place the selected
footsteps into the footstep buffer.
-
Click
Paste Footsteps to paste the selected footsteps into the viewport.
The new
footsteps appear next to the biped's current footsteps.
TipIf you have Transform gizmo on, use the
minus key (
-
)
to shrink the Transform gizmo, so it doesn’t cover up the footsteps.
- The
new footsteps can be moved as a set. Move them so the first footstep
of the new set is over footstep 7 of the original set. When footstep 7
of the original set turns red, release the mouse button.
Footsteps
from the original motion are inserted. Now there are 11 footsteps
visible.
- Press Alt+W to display four viewports.
- To
display the entire animation in the Perspective viewport, zoom
out and use Arc Rotate and Pan to adjust your view until the biped
and all 11 steps are visible.
- With
the Perspective viewport active, play the animation.
Since you
are still in Footstep mode, the Motion panel is available. This
is a good time to save your mywalk_pasted.bip file,
using Save File on the Biped rollout.
Scale
the walk:
-
Make
sure Footstep mode is active.
- In
the Top viewport, region-select all the
footsteps.
- On
the Footstep Operations rollout, turn off Length, and leave Width
selected.
- Set
Scale to 2.0 to double the spacing between
the left and right footsteps.
- Play
the animation.
The biped walks with legs apart.
- Set
Scale to 0.25 or smaller to reduce the
spacing between the left and right footsteps to half of the original
scaling (one-quarter the current setting).
If you
hadn't previously doubled this parameter, a setting of 0.5 would
have scaled the width by 50%.
Now the
biped puts one foot in front of the next.
TipIf
your character has big feet, or if it's walking on a wire or a ledge,
use Scale Width and Length to adjust the footsteps.
- Play
the animation.
The biped walks as if on a tightrope.
Bend
the walk:
- In
the Top viewport, select all the footsteps
from 7 on.
- On
the Footstep Operations rollout, set Bend to 20.0.
The footsteps
bend to the left, beginning at footstep 7.
- Play
the animation.
Walk
on uneven terrain:
You can raise and rotate the footsteps to create
the illusion of walking on uneven terrain.
- Make
sure that Footstep mode is still on.
- Maximize
the Perspective viewport.
- Use
Select And Rotate to select all the footsteps from 4 on.
- Use
the Transform gizmo arrows to rotate the selected footsteps approximately -15 degrees
about the X-axis so the footsteps go up a hill.
- Select
footsteps 8 through 11.
- Rotate
the selected footsteps about the X-axis approximately 21 degrees,
so that the footsteps go back down the hill.
- Select
footstep 11. Rotate it so it's parallel with the grid.
- Play
the animation.
The biped's feet follow the footstep placement.
Add
a jump:
If there is a period of time during a footstep
animation when neither foot is on the ground, the software interprets
this period as a jump. There are several different ways to create
a jumping animation. In this set of procedures, you’ll move footstep
keys in Track View to make the jump.
Move
footstep keys in Track View:
- Select Bip01.
On the Motion panel, in the Biped rollout, turn on Footstep Mode,
if it isn't already on.
- In
the viewport, right-click and choose Curve Editor from the quad
menu.
Track View is displayed.
- On
the Track View menu bar, choose Modes > Dope Sheet. Pan the controller
window until you can see the Bip01 Footstep track
displayed in Track View.
In Dope
Sheet display of footsteps, each blue block represents a left footstep,
and each green block represents a right footstep. The length of
the blocks is the period of time that the foot is in contact with
the ground during the footstep. The spaces between the blue and
green blocks represent periods in which the biped is not supported
by the left or right foot.
- Resize
the Track View window, or zoom into the track so you can see the
start and end frame numbers on each footstep.
- Select
footsteps 11 through 15 by drawing a box around them in Track View,
or by dragging a selection region in the viewport.
In Track
View, notice that footstep number 11 starts at frame 165.
-
On the
Track View toolbar, click the Slide Keys button.
- In
Track View, click in the center of footstep 11 and drag it to the
right until the number 166 (indicating the first frame of footstep
11) increments to number 180. Release the mouse button.
This creates
a gap between step 10 and 11. The keys in the other biped tracks
adjust to the change in the footstep track.
By creating an area in the footstep track where
neither foot is supporting the biped, you have changed a walking
step into a jumping step
- Minimize
Track View and then play the animation.
- In
the viewport, move footstep 10 so it is next to footstep 9.
- In
the viewport, move footsteps 11 through 15 so there is more of a
gap for the jump. Move these footsteps about 5–7 units in
the X-axis direction.
Now, if
you shorten the duration of footstep 10, you can accentuate the
jump.
-
On the
Track View toolbar, click Move Key.
- In
Track View - Dope Sheet, click the right edge of footstep 10.
A white
dot appears only on the right side of the key to show it's selected.
- Drag
the right edge of footstep 10 to the left to shorten the duration
of the key. Change the key so it ends at frame 160.
- Play
the animation and observe the jump.
- Turn
off Footstep Mode.
Make
the biped crouch before the jump:
The preparation for the jump, between footsteps
9 and 10, looks a little stiff because the biped is not crouching
enough before jumping. Resetting a vertical key will fix this.
-
On the
Motion panel, in the Track Selection rollout, click Body Vertical.
- Move
the time slider to frame 153, where there is a Body Vertical track
key.
- Press H and select Bip01, the center
of mass.
-
Move
the center of mass down approximately –5 units. Then
on the Key Info rollout, click Set Key.
If the biped jumps back to its original position,
click Set Key and try again. Click Set Key when you have a crouching
position as illustrated here.
- Move
the time slider to view the animation.
There appears
to be a glitch in the motion. There are two Body Vertical keys next
to each other that are causing this problem.
- Move
the time slider to frame 153.
-
In the Key Info rollout,
click the Next Key arrow to move to the next key at frame 154. Then
click Delete Key to remove this second key.
- Select Bip01
R Foot.
- Move
the time slider to frame 167. Click Body Vertical and raise the
foot slightly, so the biped's knee is bent.
-
On the
Key Info rollout, click Set Free Key to hold the bent knee position.
Set additional keys on the foot if it hyperextends before it hits
the ground, or if it goes through the ground at takeoff.
- Play
back the animation and observe the motion.
- In
the Track Selection rollout, click Body Rotation. Move the time
slider to frame 160. Using the Transform gizmo, rotate the center
of mass so the body pitches forward.
The jump
looks more natural now. The result should be similar to the jump
in footstep_jump_final.bip.