Edit Function: Drawing Curves

Before you start, please read the → “Retiming: Basics” and → “Edit Function: Settings ” chapters. They contain important explanations.

When you click on the "Edit function" button you will see a curve editor. Curves are a convenient method to create complex retiming functions:

• Press “Delete expression” and you are ready to add the curve's control points.
• Double-click on the canvas to add new control points.
• By default, control points are added with the TCB type. This type creates a smooth curve, but there are no handles to control the curve's shape. This has to be done manually under the editor's Keys > Show Key Properties. There you will find input fields for “Tension”, “Continuity”, and “Bias”.
• If you prefer Bezier splines with handles select the keys and click on the icon “Set Selected Points Type to Bezier” (A). Other modes (linear, stepped) are also allowed, and they can be combined freely.
• Bezier tangents can be unified (B), broken (C), and flattened (D) with the three icons shown below.

The easiest way to draw a curve is to define its start and end points. Let's say the

• original simulation's end time is 2.3 seconds
• retimed simulation's last frame is 116.

Now proceed as follows:

• Double-click somewhere on the canvas to set the first control point. Shift its coordinates with the two input fields. The first field represents the horizontal axis (frames), the second one is relevant for the vertical axes (seconds). Enter 0 to both fields.

• Double-click again to create another point. This time the values are 116 and 2.3.
• Select the keys and change their mode to “Bezier” (A), drag the handles to modify the curve, e.g. to create ease-in and ease-out effects, accelerations and decelerations, or plateaus.
• Additional control points can be added at any time with another double-click on the canvas. Drag them with the mouse to the desired position or enter values.
• Please be careful when you draw curves, because when the curve is decreasing playback direction will be inverted – the simulation runs backward.

You should always check the result of your operations from time to time with the built-in preview methods (see → “Retiming: Basics”). Once you are satisfied, choose your → “Input/Output Settings”, and press “Retime”.