Bind bones to shape points, Constrain motion of ik bones – Adobe Flash Professional CC 2014 v.13.0 User Manual
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Note: The Subselection tool does not work if there are multiple poses in the IK span. Before editing, delete any additional poses after the
first frame of the armature in the Timeline.
To move the location of a bone joint, head, or tail within a symbol instance, move the transformation point of the instance. Use the Free
Transform tool.
The bone moves with the transformation point.
To move an individual symbol instance without moving any other linked instances, Alt-drag (Windows) or Command-drag (Macintosh) the
instance, or drag with the Free Transform tool.
The bones connected to the instance lengthen or shorten to accommodate the new location of the instance.
Edit an IK shape
You can add, delete, and edit control points of the contours in an IK shape using the Subselection tool.
To move the position of a bone without changing the IK shape, drag the endpoint of a bone.
To display the control points of the IK shape boundary, click the stroke of the shape.
To move a control point, drag the control point.
To add a new control point, click a part of the stroke without any control points.
To delete an existing control point, click to select it, and then press the Delete key.
Note: An IK shape cannot be transformed (scaled or skewed).
Bind bones to shape points
By default, the control points of a shape are connected to the bone that is nearest to them. You can use the Bind tool to edit the connections
between individual bones and the shape control points. In this way you can control how the stroke distorts when each bone moves for better
results. This technique is useful when the stroke of a shape does not distort as you want when the armature moves.
You can bind multiple control points to a bone and multiple bones to a control point.
To highlight the control points connected to a bone, click the bone with the Bind tool
.
The connected points are highlighted in yellow while the selected bone is highlighted in red. Control points connected to only one bone
appear as squares. Control points connected to more than one bone appear as triangles.
To add control points to a selected bone, Shift-click a control point that is not highlighted.
You can also Shift-drag to select multiple control points to add to the selected bone.
To remove control points from the bone, Ctrl-click (Windows) or Option-click (Macintosh) a control point that is highlighted in yellow.
You can also Ctrl-drag (Windows) or Option-drag (Macintosh) to remove multiple control points from the selected bone.
To highlight the bones connected to a control point, click the control point with the Bind tool
.
The connected bones are highlighted in yellow while the selected control point is highlighted in red.
To add other bones to the selected control point, Shift-click a bone.
To remove a bone from a selected control point, Ctrl-click (Windows) or Option-click (Macintosh) a bone that is highlighted in yellow.
Constrain motion of IK bones
To create more realistic motion of IK armatures, you can control the freedom of motion of specific bones. For example, you can constrain two
bones of an arm so that the elbow cannot bend in the wrong direction.
By default, each IK bone is assigned a fixed length when the bone is created. Bones can rotate around their parent joint and along the x- and y-
axis. However, they cannot move in ways that require the length of their parent bone to change unless you enable x- or y-axis motion. By default,
bone rotation is enabled and x- and y-axis motion is disabled.
You can also limit the speed of motion of a bone to create the effect of weight in a bone.
In armatures with strings of connected bones, you cannot contrain the motion of the last joint in any branch of the armature. To give the
appearance of contraint of the last joint, use bones with movie clips and connect the last bone to a movie clip that has its alpha property set to
zero. Then constrain the next-to-last bone instead of the last one.
Examples:
For an arm, you could constrain the degrees of rotation of the elbow so that it cannot rotate beyond the normal range of motion of a forearm.
To enable a character to move across the Stage, turn on X or Y translation on the root bone. Turn off rotation when using X and Y
translation for more accurate movement.
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