Adobe Director Basics

ADOBE DIRECTOR BASICS
3D: Controlling action
Limited freedom
You must set the limits of a freedom before setting the motion of that freedom to #limited. If you set give a particular
motion limited freedom when the limits are all set to zero, you will see no change when you modify the value of the
limits. If you set any of the limits to a non-zero value, then set the motion of a given freedom to #limited, any changes
that you make to the limits will be respected. If you set all limits to zero, then the motion will become locked again,
regardless of any new limit settings that you apply. You will need to reset the motion to #limited for any new changes
to be taken into account.
The limitValue for angular motions has to be expressed in radians. The interface shows it in degrees.
You can double-click on any slider to reset it to its initial value.
Note that the stiffness is value of 0, which means that the joint is completely rigid. A stiffness value of 0.00001 is
extremely loose, whereas as value of 100000 gives similar behavior to a value of 0.0. If stiffness is zero and
limitValue is zero, then no movement will occur.
If stiffness is low, a motion may exceed its limitValue before easing back. If damping is also low, a freedom with
#limited motion may behave almost as if it were free.
Note: To simplify the interface, the display for #limitValue can vary between 0.0 and 180.0. This gives a good range
for both linear and angular motion, if angular motion were considered in degrees. However, angular limits must be in
the range 0.0 - 3.14159 (or pi). Angular limits need to be defined in radians, not degrees.
Drive
A D6Joint can be driven along each degree of freedom, which means you can provide both a linear and an angular
motion along each of the three axes. For each driven motion there are two types of drives. So, there are twelve
possibilities of which any six can be active at one time. The values for driveType are as follows:
#position: attempts to move the joint to a given position or orientation. An example is a piston, which pushes in
a given direction, or a door closer that rotates a door back to its closed position after it has been opened.
#velocity: attempts to move the joint at a constant speed in a given direction. An example is a train wheel. For a
wheel rigidBody, like the one in the 6DOF.dir movie, you can set the joint's axisDrive to slide the wheel along the
track, or you can set its swingDrive to rotate it around its zAxis.
These examples are illustrated below:
Last updated 8/26/2011
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