# F-Curve Modifiers¶

Reference

Panel

Sidebar region ‣ Modifiers ‣ Modifiers

F-Curve modifiers are similar to object modifiers, in that they add non-destructive effects, that can be adjusted at any time, and layered to create more complex effects.

Modifiers panel.

The F-curve modifier panel is located in the Sidebar region. Select a curve by selecting one of its curve points, or by selecting the channel list. Click on the Add Modifier menu to select a modifier.

## Types of Modifiers¶

### Generator Modifier¶

Generator creates a Factorized or Expanded Polynomial function. These are basic mathematical formulas that represent lines, parabolas, and other more complex curves, depending on the values used.

This option causes the modifier to be added to the curve, instead of replacing it by default.

Polynomial Order

Specify the order of the polynomial, or the highest power of X for this polynomial. (Number of coefficients: 1.)

Change the Coefficient values to change the shape of the curve.

### Built-in Function Modifier¶

These are additional formulas, each with the same options to control their shape. Consult mathematics reference for more detailed information on each function:

• Sine

• Cosine

• Tangent

• Square Root

• Natural Logarithm

• Normalized Sine (sin(x)/x)

Amplitude

Phase Multiplier

Phase Offset

Value Offset

### Envelope Modifier¶

Allows you to adjust the overall shape of a curve with control points.

Reference Value

Set the Y value the envelope is centered around.

Min

Lower distance from Reference Value for 1:1 default influence.

Max

Upper distance from Reference Value for 1:1 default influence.

Add a set of control points. They will be created at the current frame.

Point
Frame

Set the frame number for the control point.

Min

Specifies the lower control point’s position.

Max

Specifies the upper control point’s position.

### Cycles Modifier¶

Cycles allows you add cyclic motion to a curve that has two or more control points. The options can be set for before and after the curve.

Cycle Mode
Repeat Motion

Repeats the curve data, while maintaining their values each cycle.

Repeat with Offset

Repeats the curve data, but offsets the value of the first point to the value of the last point each cycle.

Repeat Mirrored

Each cycle the curve data is flipped across the X axis.

Before, After Cycles

Set the number of times to cycle the data. A value of 0 cycles the data infinitely.

#### Trivially Cyclic Curves¶

When the Cycle Mode for both ends is set to either Repeat Motion or Repeat with Offset, and no other options of the modifier are changed from their defaults, it defines a simple infinite cycle.

This special case receives some additional support from other areas of Blender:

• Automatic Bézier handle placement is aware of the cycle and adjusts to achieve a smooth transition.

• The Cycle-Aware Keying option can be enabled to take the cycle into account when inserting new keyframes.

### Noise Modifier¶

Modifies the curve with a noise formula. This is useful for creating subtle or extreme randomness to animated movements, like camera shake.

Blend Type
Replace

Adds a -0.5 to 0.5 range noise function to the curve.

Adds a 0 to 1 range noise function to the curve.

Subtract

Subtracts a 0 to 1 range noise function to the curve.

Multiply

Multiplies a 0 to 1 range noise function to the curve.

Scale

Adjust the overall size of the noise. Values further from 0 give less frequent noise.

Strength

Adjusts the Y scaling of the noise function.

Offset

Offsets the noise in time.

Phase

Adjusts the random seed of the noise.

Depth

Adjusts how detailed the noise function is.

### Limits Modifier¶

Limit curve values to specified X and Y ranges.

Minimum, Maximum X

Cuts a curve off at these frames ranges, and sets their minimum value at those points.

Minimum, Maximum Y

Truncates the curve values to a range.

### Stepped Interpolation Modifier¶

Gives the curve a stepped appearance by rounding values down within a certain range of frames.

Step Size

Specify the number of frames to hold each frame.

Offset

Reference number of frames before frames get held. Use to get hold for (1-3) vs (5-7) holding patterns.

Use Start Frame

Restrict modifier to only act before its “end” frame.

Use End Frame

Restrict modifier to only act after its “start” frame.