An FFGL effect that traces the outlines in the current frame and draws them with a slow pen on paper the ink stays on. A trapezoidal motion planner with a speed limit, an acceleration limit and a stop at sharp corners moves the carriage by the time that actually passed, and the renderer lays down ink per unit of time, so the line is heavy where the pen is slow, every pen-down is a blot, a coarse step pitch draws staircases, and a carousel of pens costs a trip for every colour change. A few strokes in, the clip has moved on, so the sheet ends up a collage of moments.
This demo runs the plugin's shaders in your browser, so it needs JavaScript and WebGL2. The plugin itself, its source and its downloads are on its repository.