Animating for Games - Game Character Development with Maya - page 952

FIGURE 16.7 Spline, Clamp, Linear, Flat, and Stepped tangents
2. Press F in the Graph Editor's main window to frame the animation curve. As you
can see, this first cube has a Spline Tangent applied to it. This makes the curve
flow smoothly between all the keys.
3. Select the next cube, Cube_Clamped. This tangent is a hybrid of two others, the
Linear and Spline tangents. Unless two keys are similar in value, all the tangents
will be set to splines. As you can see in Figure 16.7b , the first two keys have the
same value, so their tangents are set to Linear; the third key has a higher value, so
the tangents leading out of the previous key and into this are set to Spline.
4. Next, look at the cube called Cube_Linear. This type of tangent creates a simple
linear path between keys ( Figure 16.7c ) .
5. Now select Cube_Flat. As you can see in Figure 16.7d , instead of the cube follow-
ing a straight linear path from key to key, it now moves along to the second key
and then eases out of it before easing into the final key. This creates a gradual
smooth motion when the object starts to move or comes to a stop.
6. Finally, look at the Stepped tangent shown in Figure 16.7e ; this is applied to
Cube_Stepped. Unlike the others, this one does not flow along a path as such;
rather, it will snap from key to key without being interpolated.
Eachofthesetangentsdiscussedherecanbeappliedtoanycurve,byeitherclicking onthe
tangent'sbuttonfoundontheGraphEditortoolbar,orfromtheTangentsmenuineitherthe
Graph Editor or the Time Slider contextual menu.
As well as altering the tangents on a whole curve, you can also select each key and apply
them individually. With a key selected in the Graph Editor, you can also edit the curves
manually using the two handles that appear. These can be moved around until you achieve
the motion you require ( Figure 16.8 ).