Adobe Director Basics

ADOBE DIRECTOR BASICS
3D: Controlling action
Terrains
Where possible, use several small terrain objects, placed side by side. Using a single large terrain can lead to
performance issues. For your own projects, you may wish to find the optimal balance between multiple terrain objects,
the terrain dimensions and the polygon count for each individual terrain.
Ray casting
Using rayCastAll() and rayCastClosest() are both significantly faster than the native 3D ray-casting methods.
However, even with the simplified geometry used by rigidBody proxies, ray casting can be an expensive operation if
the scene is full of rigidBody objects. Unlike the native 3D ray-casting methods, the Dynamiks xtra does not allow you
to limit the number of objects that the ray will consider, nor does it allow you to indicate a maximum distance at which
to stop searching.
If you are sending multiple ray casts on every frame into a crowded scene, you may like to check whether this is
affecting the rate of playback. If so, you may wish to explore alternative techniques. Here are a couple of examples.
Create a parallel scene with 3D models with very simple geometry and remove it from the world. Use the native
member3D.modelsUnderRay() on a subset of these simple models.
Use a path-finding algorithm, such as A* (see “Finding a path” on page 229) to find a pre-determined path through
a maze of obstacles.
CPU-friendly code
3D operations may not be the only bottleneck in your project. You may unwittingly be creating scripts that use
inefficient techniques.
Both JavaScript and Lingo provide multiple ways for achieving the same ends. A script that uses few lines of code is
not necessarily faster than one that uses more precise commands. This is especially true when using repeat loops.
Placing timer points in your scripts
In any complex process, there may be certain operations that take longer than others. The most likely places to improve
performance are in those operations that take the longest. To determine where these are, you can place timer points in
your script.
To test this concept, download the movie Suspend.dir. At the end of the on beginSprite() handler in the
SuspendUpdates Demo behavior, you will find three lines commented out. Uncomment these lines and launch the
movie. Watch the output in the Message window.
Last updated 8/26/2011
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