Thinking Outside the Box:
Adjusting Your Biped

By Paul "Villam" Steed

The selected, scrawny, boxy individual is known as Mr. Biped. Biped is basically half of CS with Physique being the other half.

Next, we need to adjust the structure of the biped to match our model complexity (all those toes and digits won’t be necessary). With any part of but not all the biped selected go to your Motion command panel and click the Figure Mode button…

‘Figure Mode’ becomes more apparent in its effect later on when you begin applying animations to your biped. For now understand that this mode is mainly to tweak low level parameters of your biped or to provide a nice default position from which to attach or detach the biped to a mesh.

Now expand the Structure sub-directory by clicking on it and change the following parameters:

• Spine Links to 3
• Fingers to 1
• Finger Links to 2
• Toes to 1
• Toe Links to 1

Play around with the other settings and make sure you know the names for the various body parts of the biped. The reason for the toes and fingers is because this particular character like most I the game have mitts for hands and don’t really need to have the utility of all their digits. Changing the spine links are subjective and don’t have to be changed, I just prefer this number of links.

Now we’re ready to start NU Scaling the biped to match the model. First, hide the appendages on its right side since we’ll be using CS’s Mirror function to copy that info once we’re done. Next, grab the center of mass of the biped and pull it down to just above the top of the bottom edge of the crotch of the model and scale the yellow pelvis along the Z axis until it looks like this…

Note I rotated the leg slightly to make sure the hip pivot point is correct.

Scale the Thigh, Calf, Foot and Toe to match the mesh as close as you can. Don’t worry if they’re not exactly matching. You’ll see later on it doesn’t have to matter. As you adjust the leg keep in mind some rules of thumb I’ve picked up:

• start with the hips and work your way down
• freezing the model keeps you from accidentally selecting it
• remember that moving a foot will make the leg adjust accordingly
• don’t be afraid to adjust your mesh to better fit your leg
• also don’t be afraid to not have your biped match your model exactly
• remember that the hip, knee, ankle and toe joints are crucial to setting up the biped/model match; experiment with the motion of your biped joints to see exactly where they bend and envision your model deforming as it bends from that point with its given geometry
• turn the legs of your mesh so they’re facing forward
• scale the biped in the front view first and then the side view
• make sure the feet are scaled so that the bottom edge of the biped foot is flush with the bottom edge of the model’s foot.

Cool. Now go to first Spine link, select it and notice you can actually move it around as well as rotate or scale. Drag the upper body up so it matches the position of the upper model torso. This is extremely important since in Q3:A the upper and lower body have to be separate geometry and their juncture point is very important. In this case the bottom of the spine needs to be at the belt line exactly. Next, scale the top Spine link to help visually sense the chest of the character and scale the Clavicle along the X axis until the shoulder joint is at the right spot. Rotate the arm a little, too.

(Continued on next page)