Escapement

Escapement models an optical video feedback rig: a camera looking at a screen that is showing what the camera saw a field ago, through glass that splits the light into several paths, with a proc amp in the cable and an operator playing the gain against unity. It ships as two plugins, because FFGL resolves a single entry point per binary — Escapement is a source, and Escapement Feed is an effect that injects your clip into the loop, so the fractal is built out of the footage rather than laid over it.

The fractals are what the loop settles into. Nothing in it evaluates a fractal. A tap is one path from the screen back into the camera, a set of taps is an iterated function system, and the attractor of that system is the fractal — so the Sierpinski rig really is three affine maps, and the gasket assembles itself out of sensor noise. The Koch snowflake is a four-tap curve plus a three-fold mirror wedge, which is a thing the rig could actually have.

Endless zoom falls out of that rather than being engineered. The camera's zoom is a per-field multiplier applied to the picture, not a coordinate anyone stores, so after a thousand fields at 1.02 the magnification is a number that never exists anywhere in the plugin — there is nothing to overflow. The Julia and Mandelbrot rigs are the exception, because they are the only part that holds a coordinate; they get double-float arithmetic to reach about 1e13.

A rig with every knob held still converges on its attractor and then stops, which is a theorem rather than a bug. Real rigs never settle because a person is always moving the cameras, so Drift is that person — slow, at rates with no common multiple, and scaled by how stiff each rig is. It is on by default in every one of the twelve presets.