样条线编辑器Spline Editor

难度LEVELL3 · 高级L3 · Advanced 领域TOPIC视觉特效

先学：Prerequisites: 关键帧与动画

学习目标LEARNING OBJECTIVES

学完你能打开样条线编辑器（Spline Editor）看懂动画曲线，并用平滑与压平把匀速动作调出缓入缓出（Ease In/Out）。

概念说明CONCEPTS

样条线编辑器（Spline Editor）把关键帧之间的数值变化画成可调的曲线——横轴是时间，纵轴是参数值，曲线越陡，变化越快。

  • 默认匀速直线：Fusion 默认线性插值（Linear Interpolation），动作匀速前进，看起来机械。
  • 曲线勾选才显示：面板左侧列出所有动画过的参数，勾上复选框，曲线才进入右侧图表区。
  • 平滑出缓动：框选关键帧后点左下 Smooth（或按 Shift-S），折线变成进出柔和的 S 形曲线。
  • 压平做停顿：右键某个关键帧选 Flat，该键前后自动减速，适合"缓缓停住"。
  • 手柄精调速度：选中关键帧会露出贝塞尔手柄，拖长拖短直接改变加速度。

操作步骤STEPS

  1. 选中带关键帧的节点，点击界面右上 Spline 打开样条线编辑器
  2. 在左侧参数列表勾选要看曲线的参数
  3. 点击编辑器右上 Zoom to Fit，让曲线充满图表区样条线编辑器里勾选参数并充满视图
  4. 框选全部关键帧，点击左下 Smooth 或按 Shift-S 把折线变圆滑
  5. 右键要缓动的关键帧选 Flat，按空格回放对比速度变化压平关键帧后的缓入缓出曲线

练习PRACTICE

  1. 把一段位移动画的全部关键帧做 Smooth，回放对比与匀速版的区别。
  2. 只在最后一个关键帧上右键选 Flat，做出"缓缓停住"的收尾。

常见问题FAQ

左侧列表里找不到我的参数？

只有动画过的参数才会出现，且要勾选复选框才显示曲线。曲线太挤时点 Zoom to Fit 自动缩放全览。

Smooth 之后动画变慢了吗？

没有。平滑只改键与键之间的速度分布，关键帧的位置和数值不动；不满意按 Command/Ctrl-Z 撤销。

怎么回到原来的匀速直线？

选中关键帧后右键选 Linear，曲线恢复成直线，动作重新匀速。

Learning Objectives学习目标

After this card you can read animation curves in the Spline Editor and turn robotic constant-speed motion into eased moves with Smooth and Flat.

Concepts概念说明

The Spline Editor draws the value change between keyframes as an adjustable curve — time runs left to right, the parameter value runs bottom to top, and a steeper curve means faster change.

  • Linear by default: Fusion starts with Linear Interpolation — constant speed, which looks mechanical.
  • Curves show only when checked: the left header lists every animated parameter; tick its checkbox to draw the curve in the graph.
  • Smooth for easing: lasso keyframes and click Smooth at the bottom left (or press Shift-S) to bend straight lines into gentle S-curves.
  • Flat for settling: right-click a keyframe and choose Flat to slow the motion just before and after it — perfect for easing to a stop.
  • Handles fine-tune speed: selected keyframes reveal Bézier handles; dragging them reshapes the acceleration directly.

Steps操作步骤

  1. Select the keyframed node and click Spline at the top right to open the Spline Editor
  2. Tick the checkbox of the parameter whose curve you want to see in the left list
  3. Click Zoom to Fit at the editor's top right to fill the graph with the curveFitting the curve in the Spline Editor
  4. Lasso all keyframes and click Smooth at the bottom left (or press Shift-S) to round the corners
  5. Right-click the keyframe you want to ease and choose Flat, then press Spacebar to compareAn eased curve after flattening a keyframe

Practice练习

  1. Smooth every keyframe of a position animation and play it against the linear version.
  2. Right-click only the final keyframe and choose Flat for a "settle to a stop" ending.

FAQ常见问题

My parameter is missing from the list?

Only animated parameters appear, and a curve shows only when its checkbox is ticked. If the graph feels cramped, click Zoom to Fit.

Does Smoothing make the animation slower?

No. Smoothing only redistributes speed between keys — keyframe positions and values stay put. Undo with Command/Ctrl-Z if you dislike it.

How do I get constant speed back?

Select the keyframes, right-click, and choose Linear — the curve straightens and the motion runs evenly again.

深度资料：样条线编辑器 →Deep dive: 样条线编辑器 →

本卡术语Terms in this card

关键帧Keyframe 变速Speed 曲线Curves Fusion 合成Fusion 节点Node