Gnarl
A gnarly distortion effect

Distance Map Selects a luminance map layer to modulate the distance of the distortion. (optional)
Offset Shift the Distortion Field
Angle Rotate the Distortion Field
Gnarl Sets the maximum distance of the distortion
Horizontal Stretch Amount to stretch the distortion field horizontally
Vertical Stretch Amount to stretch the distortion field vertically
Field Density x The horizontal size of the field prior to stretching
Field Density y The vertical size of the field prior to stretching
Edge Behavior Method for handling pixels on and beyond the edges of the layer
Power Morphs smoothly into (or out of) the effect.
Super Sample Off, High, or Extreme. Higher quality, slower rendering.