Advanced Animation: Interpolation, Easing, and the Graph Editor

Chapter 6's own tip box pointed here directly: a rigged character's own posed bones get keyframed the same way Blender Fundamentals' own Chapter 8 keyframed whole-object transforms, but this chapter gives considerably finer control over exactly how those poses move between keyframes.

Beyond Automatic Smoothing: What the Graph Editor Reveals

Blender Fundamentals' own Chapter 8 relied on interpolation happening automatically, invisibly, between two keyframes. The Graph Editor makes that same interpolation directly visible and editable, as an actual curve plotted against time, rather than a hidden calculation running in the background.

F-Curves: Visualizing a Keyframed Value Over Time

An F-Curve plots a single animated property's own value against time directly — a bone's rotation angle rising and falling across the Timeline's own frames, shown as an actual visual curve rather than an abstract set of numbers. Reading this curve's own shape reveals exactly how a motion accelerates, decelerates, or holds steady, at a glance.

Interpolation Modes: Constant, Linear, and Bezier

Constant interpolation holds a value fixed at one keyframe's own setting, then jumps instantly to the next keyframe's value with no transition at all — useful for a strobe-light effect or a hard, deliberate snap. Linear interpolation changes a value at a perfectly steady, constant rate between two keyframes. Bezier interpolation (Blender's own default) produces a smooth curve that eases in and out of each keyframe, rather than moving at a constant rate throughout.

Easing: Ease In and Ease Out

Easing describes how a motion accelerates or decelerates near a keyframe rather than moving at a constant speed the whole time — easing out means slowing down gradually as a motion approaches a keyframe, easing in means starting gradually rather than snapping instantly to full speed. Real physical motion almost always eases this way; objects don't typically start or stop moving at a perfectly constant, unchanging speed.

Editing Curve Handles Directly for Custom Timing

Each keyframe's own F-Curve has adjustable handles controlling exactly how sharply or gradually the curve eases into and out of that specific point — the same underlying handle concept Vector Graphics' own Chapter 3 covered for bezier curves on a 2D path, applied here to a curve plotted against time instead of 2D space. Dragging a handle longer produces a more gradual, drawn-out ease; a shorter handle produces a snappier, more abrupt transition.

Why This Matters More for Character Animation Than Simple Object Motion

A ball rolling in a straight line often looks perfectly fine with default automatic interpolation. A character's own arm swing, a head turn, or a walk cycle reads as noticeably more lifelike with deliberately shaped easing — a slight pause at the top of a gesture, a quicker snap on a strike, a gradual settle at the end of a movement — exactly the kind of nuance the Graph Editor's own direct curve control makes possible.

Hands-On Exercises