Animation is used throughout 3ds max. It is possible to animate the position, rotation, and scale of an object, and almost any parameter setting that effects the object’s shape and surface. It is possible link objects for hierarchical animation, using both forward and reverse kinematics, and to edit the animation in Track View.
This section discusses the basics of creating animation. It looks briefly at a comparison between computer animation and classic hand-drawn animation, and then describes the creation of “Key Framed” animation, using the “Animate” Button.
Key Frames are the ones, where you define the animation for a parameter by specifying its exact value at a given set of times. The computer can then work out by interpolating what the value should be between the keys.
Time Controls can be found on the lower interface bar between the key controls and the Viewport Navigation Controls. The Time Control buttons include buttons to jump to the Start or End of the animation, or to step forward or back by a single frame. You can also jump to an exact frame by entering the frame number in the frame number field. The Time Controls also include the Time Slider found directly under the viewports.
Figure 6-1: Time Controls
The Time Slider provides an easy way to move through the frames of an animation. To do this, just drag the Time Slider button in either direction. The Time Slider button is labeled with the current frame number and the total number of frames. The arrow buttons on either side of this button work the same as the Previous and Next Frame (Key) buttons.
Figure 6-2: Time Slider
The Track Bar is situated directly under the Time Slider. The Track Bar displays a rectangular marker for every key for the selected object. These markers are color-coded depending on the type of key. Position keys are red, rotation keys are green, scale keys are blue, and parameter keys are dark gray. The current frame is also shown in the Track Bar as a light blue transparent rectangle.
Figure 6-3: Track Bar
The Track Bar shows key markers only for the currently selected object or objects, and each marker can represent several different keys. When the mouse is moved over the top of these markers, the cursor changes to a plus sign, and a marker can be selected by clicking on it. Selected markers turn white. Using the Ctrl key, you can select multiple keys at the same time. You can also select multiple key markers by clicking an area of the Track Bar that contains no keys and then dragging an outline over all the keys you want to select. If you move the cursor over the top of a selected key, the cursor is displayed as a set of arrows enabling you to drag the selected key to the left or right. Holding down the Shift key while dragging a key creates a copy of the key. Pressing the Delete key deletes the selected key.
Animation with Key Frames
Keys define a particular state of an object at a particular time. Animations are created as the object moves or changes between two different key states.
The easiest way to make keys is using the Key Controls. These controls are located to the left of the Time Controls.
Figure 6-4: Key Controls
Max includes two animation modes: Auto Key (N) and Set Key ( ' ).You can select either of these modes by clicking the respective buttons at the bottom of the interface. When active, the button turns bright red, and the border around the active viewport also turns red to remind you that you are in animate mode. Red also appears around a spinner for any animated parameters.
Auto Key Mode
With the Auto Key button is enabled, every transformation or parameter change creates a key that defines where and how an object should look at that specific frame.
To create a key, drag the Time Slider to a frame where you want to create a key and then move the selected object or change the parameter, and a key is automatically created. When the first key is created, Max automatically goes back and creates a key for frame 0 that holds the object’s original position or parameter. Upon setting the key, Max then interpolates all the positions and changes between the keys. The keys are displayed in the Track Bar.
Each frame can hold several different keys, but only one for each type of transform and each parameter. For example, if you move, rotate, scale, and change the Radius parameter for a sphere object with the Auto Key mode enabled, then separate keys are created for position, rotation, scaling, and a parameter change.
Set Key Mode
The Set Key button ( ' ) offers more control over key creation and sets keys only when you click the Set Key button (K). It also creates keys only for the key types enabled in the Key Filters dialog box. You can open the Key Filters dialog box, by clicking the Key Filters button. Available key types include All, Position, Rotation, Scale, IK Parameters, Object Parameters, Custom Attributes, Modifiers, Materials, and Other (which allows keys to be set for manipulator values).
Figure 6-5: Key Filters Dialog Box