In previous tutorial, i have teach you how to add bone to a character. But, if you test by moving the bone, the character look wired. So, we need to optimize the bone in order to have best result when doing animation.
Part 2 – Optimizing the character and bones use for animation.
Step 1. Optimize body bone
The body bone is use to hold the body shape and it is the root of all bone. When we need to move the position of the character, we can move this bone. To adjust the shape affected by the body bone. We need to use the binding tool. Press and hold on the bone tool icon in the toolbar, the binding tool icon will appear. Select it.
Select the body bone and the knot affected by this bone will be highlighted with yellow color.
Press on the knot and drag on the bone and connect the knot and bone. To remove control points from the bone, Ctrl-click (Windows) or Option-click (Macintosh) a control point that is highlighted in yellow.
Connect the knot and the body bone like show below.
Step 2. Optimize hip and shoulder bone
Shoulder bone is use to connect the arm and hip bone is use to connect the leg and the body. In this character, these bone only use for connection and they will not affect the shape. So, we need to fix the position and rotation of these bones.
First, we disable all the connection from these bone to the shape. Select binding tool and click on the left shoulder bone. You can see some knot of the shape are highlighted. To remove control points from the bone, Ctrl-click (Windows) or Option-click (Macintosh) a control point that is highlighted in yellow. Repeat for right shoulder and the hip bones.
Second, we need to disable the rotation of the bone. Use the select tool to select the shoulder bone. Then you will see the option panel for joint:rotation. click on the “enable” check box to disable it.
Repeat for the right should and two hip bone.
Step 2. Optimize head and neck bone
The head and neck bone is use to control the movement of head. To have a better result, i have to limit the movement of the neck and head bone.
Select the neck bone. From the properties panel. Set the rotation constriant to -15 to +15 degree.
Then, only connect knots near the neck area.
Select the head bone. From the properties panel. Set the rotation constriant to -20 to +20 degree.
Then connect the rest of the knots in head area to the head bone.
Now, you can test the head movement. Use the select tool and select the head bone. Drag and move the bone and you can see the head move with the bone.
Step 3. Optimize arm and bone
Now, for the arms. First, we need to set the connection for each bone. Start from right arm, select upper arm bone. Use the binding tool to set the knot connection near the bone like the figure show below.
Select lower arm bone. Use the binding tool to connect the knot to arm bone like the figure show below.
Select hand bone. Use the binding tool to connect all knot from the hand to the bone.
Now, we set the rotation constraint for each bone.We limit the ratation of the upper arm from -10 to +70 degree. This will make sure the arm will not collapse with the body and head.
Then we limit the rotaiton of the lower arm from -80 to +0 degree.This make the arm move more nature.
Now, we test the movement of arm. The arm look strange when i move the bone.
We need a further tweak on the shape. First, we add one more point on the arm. Use the add anchor tool (Key “+”) click on the arm and add a point. Move the point and make the shape like this. You can also delete some unusual point by using the remove anchor tool (Key “-“).
Then, we reconnect some point to the bones.
Now, the arm look better.
Repeat the steps with the left arm.
Step 4. Optimize leg and bone
Now, for the legs, similar to the arm. We also need to connect the shape to the bone and limit the rotation of the bone.
Select the upper leg bone. Use the binding tool to connect the upper area shape to the bone.
Select the lower leg bone and connect the lower leg shape.
Last, select the foot bone and connect the foot shape.
Now, we set the rotation constraint for each bone.We limit the ratation of the upper leg from -45 to +25 degree.
Then we limit the rotation of the lower leg from 0 to +45 degree.
Limit the rotation of foot from 0 to +45 degree.
Now, you can test moving the bone. You can see the shape move with the bone like a skin of the bone. If the shape not moving correctly. You can adjust the connection between bones and knot.
In next tutorial, you will learn how to animate this character.
Flash CS4 Animation with Bone Part 3