Filter

The Filter node shapes the terrain’s frequency content using an audio-inspired parametric filter. Useful for isolating or suppressing features at specific scales.

Properties

• Mode

  • LowPass: Allows only low frequencies (large-scale features) to pass. Removes fine details.

  • HighPass: Allows only high frequencies (small-scale details) to pass. Removes broad shapes.

  • LowShelf: Boosts or cuts all frequencies below the selected frequency with a gentle slope.

  • HighShelf: Boosts or cuts all frequencies above the selected frequency with a gentle slope.

  • BandPass: Passes only a narrow band of frequencies around the selected center. Blocks both lower and higher frequencies.

  • Notch: Sharply removes a narrow frequency band. Ideal for cutting specific scale artifacts.

  • Bell: Bell-shaped EQ mode for boosting or cutting a selected frequency band more smoothly.

• Frequency Sets the center frequency (scale) to target. Lower values affect broad, large-scale features; higher values focus on fine detail.

• Gain Controls the strength of boost or cut. Positive values amplify the selected frequency; negative values reduce it.

• Q Adjusts the sharpness or width of the filter. Low Q = broad, gentle slope. High Q = tight, precise filtering.

• Keep DC When enabled, preserves the overall elevation offset (DC component) of the terrain, preventing unwanted flattening or vertical shifting.