The layer type that the source accepts.

See Signatures for more information.

Rotates the position at which the pixels are sampled by this angle. An angle of 90 degrees would mean that the x derivative would be equal to the y derivative of an angle 0.

Multiplies the output value by this amount.

Adds this amount to the output value.

Determines if derivatives at the boundary should read outside the image or restrict to the image range. Reading outside is useful for building seamless textures with wrap-mode. But restricting to the image range avoids artificial flattening of the derivative at the boundary in clamp modes, as it acts more like an extrapolation.

Usually a derivative is computed with adjacent pixels, but if the values are slowly varying there may not be enough bit-depth to get smooth derivatives. This will expand the distance (in buffer elements) to compute the derivative, possibly removing stepping artifacts from the derivative.