The Terrain Warp operator can be used to distort a terrain grid horizontally with noise.
The warp function works by taking an input vector (either a grid cell’s position, or the direction from the grid cell to the center of the grid) and then applying noise to the vector and resampling the grid using that distorted vector. The grid value sampled at that distorted position is then re-applied back to the original grid cell position as a modified height value. The result is a horizontal warp effect.
Classic: when enabled, the vector input into the noise function will simply be each grid cell’s position.
Directional: when enabled, the vector input into the noise function will be constructed from each grid cell’s position relative to the grid center, and rotated by the specified angle.
Angle: the specified angle to rotate the directional vectors by.
Clamp: when enabled, points sampled by the warp function outside of the grid bounds will be clamped to the values at the grid bounds.
Loop: when enabled, points sampled by the warp function outside of the grid bounds will be looped around and resampled at the opposing side of the grid.
Sample neighbor grids: when enabled, points sampled by the warp function outside of the grid bounds will be sampled from the nearest neighbor grid, if it exists.