Modulate effects using curves

The evaluate_fcurve node remaps the input x to the output y based on a editable function curve. It is useful for modulating effects using a custom profile, such as for falloffs and more.

Function curves default to the range [0, 1]. However, you can define points at horizontal and vertical positions outside this range.

If desired, choose a preset curve as a starting point from the Options menu (click ) before editing it as you like.

1. Click on a point to select it, or click and drag a box to marquee-select multiple points. Shift-click to toggle the selection of individual points. Press the Delete or Backspace key to remove the selected points. Drag selected points to change their positions and values. For Bezier points, you can also drag the tangent handles to adjust the slope. Right-click on a point for other options, including:

   • Break Tangents to adjust the left and right tangent handles separately.
   • Unify Tangents to lock the handles together.

2. Click on the curve to add a point, and then drag it to the desired location.

3. Navigate the curve editor using the Alt key:

   • Alt+middle-click and drag to pan.
   • Alt+right-click and drag to zoom in and out.

4. Use the buttons at the upper right to:

   • Open the curve in a separate, resizable window.
   • Frame all points on the curve.
   • Open the options menu. This is the same menu as displayed when you right-click in the background of the curve editor in a floating window.

5. Use the controls below the curve to:

   • Select a point in order from left to right.
   • Edit the selected point.
   • Set the value or interpolation of multiple points.
   • Customize the extrapolation of the curve before the first point and beyond the last point.