ISF

Runs an ISF (Interactive Shader Format) shader loaded with Load .fs.... The shader’s inputs determine the available parameters.

Parameter	Control	Notes
Shader	file picker (Load .fs...)
Blend	Selector	Add, Multiply, Screen, Difference, XOR, Replace, or Phoenix into the chain.
Mix	Trough	Wet/dry of the shader’s result.
Shader Inputs	varies	Generated from the loaded shader’s own metadata; shape and count vary shader to shader.

The module’s Insert FX run after the shader. See Insert FX Chains.

Filters and generators

A shader whose header declares an input with "TYPE": "image" (usually named inputImage; transitions declare two) is a filter and reads the chain. A shader with no image input is a generator.

A filter receives the chain over black. Its result, after the module’s own Insert FX, keeps the chain’s see-through areas: wherever the chain above has anything, the result is kept as drawn; where the chain is empty, only the parts the shader lights are kept and dark parts stay empty. A generator’s result is used as drawn, with its own alpha. See Signal Chain.

NOTE: a filter set to Blend XOR or Phoenix treats a dark result over an empty area as empty.

Related: AUX Sends and Buses.