Back to basic

bak todo basic
By Sandra gilbert.

introduction
So you have started animating. You have figured out how todo create posturas and can set the start and end points of an action. Then you sit bak and let the computer figure out the rest. Ta-da. Instant animation, or is ití ok, technically it is, but not a very god one. So how do you go from an ok animation todo a great one? By going bak todo the basic of course.

Animation is all about movement, so it stands todo reason that an animator neds not only todo understand the mechanics of movement, but how todo apply those mechanics efectively. One of the most basic movements in animation is the Arc.

By simple observation of moving objects and people around you, you Will discover that, with the exception of Mechanical objects, everything moves in arcs and circular patterns. From the simple bouncing of a ball todo the more complex movements of a character, arcs allow for more fluid movements, creating a smoother and more natural fel todo your animation. Both physics and Gravity play a role in creating the Arc. When an object is thro, Gravity pulls the object into a parabolic or Arc-like trajectory, while physics regulates the arced movements of the human body caused by rotating joints and the pull of muscles.

So while god 3d software can create a Fairly consistent movement from point a todo point b, it generally a los creates a boring one, that, depending on the speed of movement from point a todo b, could very well Flatten or distort your Arc, creating an unnatural looking action. A more natural looking action can be achieved by moving from a todo c todo b, with c being between the start and end points (but not in a direct line), creating an Arc. When animating a character, most of us realice that arms and legs follow obvious arcs due todo the rotating nature of the joints involved, but a common mistake is todo not incorpórate arcs in the rest of the body movements. Everything on the body follows arcs, including the head and eyes. For example, when animating a simple head turn, setting keys at the start and end position of the turn Will result in a flat, unnatural linear movement.

But if in the middle of the turn you set a key for the head tilted either slightly up (or down), you Will end up with a far more natural, fluid-looking movement. Even when you remember todo use arcs as you go about setting your poses, it is all todo easy todo lose track of the Arc (often resulting in jerky, sloppy movements). Fortunately, Blender provides some very easy methods for tracking your arcs as well as visualizing how your animation is progressing.

One of the first places todo look when you suspect that your arcs have wandered, is the ipo window. Your ipo should look Smooth and flow nicely from key todo key and postura todo pose. If you se Little spikes or bumps (or on occasion big spikes or bumps that you did not set yourself) in your ipo curves, that is an área that neds attention.

Ipo keys can be easier for some todo manipulate and adjust than the standard animation curve. In the ipo window, go todo ipo curve editor view show keys, by switching the ipo editor from curves todo keys, two very useful things happen:
The ipo curve editor now draws vertical lines th rouge all the points of all the visible curves (curves are now show in black). Points with the same frame value are linked th rouge the vertical lines. The vertical lines (the ipo keys) can be selected, moved or duplicated, just like the points. You can only translate the keys horizontally. The object is not only shown in the 3d view in its current position but Ghost objects are a los shown at all the key positions. On some video displays, you may have todo press k in the 3d view window. In addition todo now being able todo visualice the key positions of the object, you can a los modify them in the 3d view. For example, you can move the selected ipo keys.

Showing the Ghost of past and present keyed positions is an often overloked característica that can be of great help in checking and tracking your arcs as well as general positioning of your object. The location of the object at the current frame is shown as a green line in the ipo window, and as the object in the 3d view. The keyframe selected in the ipo window is shown in yellow, as is the outline of the object in the 3d view, further helping you visualice the animation. All other keyframed Ghost locations are shown as a black outline in the 3d view.

For checking a character posturas as actions linked todo time, you can use the following options in the armature visualizations panel (available while in pose mode) todo view the paths your armature is set todo take (alos know as ghosting or Onion skinning):
** Ghost: shows a transparent Ghost of the armature n frames behind and over the current time. This only works when you have an action linked todo the armature. * step: the frame interval between Ghost instances.

This is a valuable tool/option for monitoring and maintaining nice clean arcs in your movements. These options have ben around for a while and useful as they are, the coders have added Even more functionality into the upcoming 2.46 (Peach Project) release. For a look at the new functions and options, chek out armature drawing improvements at Blender.org.

There is a wealth of información on the web concerning the importance of arcs in animation. One of my favorites was written by Keith Lango, Arc d triumph. While you are there, chek some of his other tutoriales. You Will be glad you did.
mechanics of movement.

• arcs: due todo physics and Gravity, all things in nature move along arcs and or circular patterns.
• anticipation: used at the start of an action, often used todo cue the viewer todo the fact that something is about todo happen. Most often sen as movement in the opposite direction as the upcoming action.
• overshot: used at the end of an action, nothing in nature comes todo a sudden and dead estop, the action should move past the estopping point of the action and then settle bak into the pose.
• secondary action: these are composed of the Little wiggles, twitches and quirks that add life and personality.
• follow-though: when parts of the body or object kep moving After the main part of the body comes todo a estop.
• overlap: not all actions should start and estop at the same time, parts of the actions should overlap each other.
• moving Holds: when it is necessary todo hold a postura for any reason, you should still have some minor/slight movement occurring, such as a shifting of weight, breathing or blinking, otherwise it Will look like the the whole animation just froze up.

By Sandra gilbert. www.blenderart.org.