Lightning reveal guide

Overview

Lightning reveal sends a branching electric strike across a picture from the point you tap, and can crack that picture open into a second one.

Red branching lightning over the crown and brow of a pale, gold-haloed figure, with a second picture showing through in torn patches along the branches
Crimson strike partway through: picture B shows in patches along the branches.

The strike draws a Lichtenberg figure, the branching pattern a dielectric breakdown burns into wood or glass. It grows from the point you tap, the strike origin.

Before a strike plays, the tool grows its tree on a small grid of picture A. Each new piece is picked at random from the cells next to the tree, and cells on edges and bright areas are far more likely to be picked, so the branches run along the shapes in the picture. See edge detection and branching.

Then the strike races out along the tree in the order it grew. Each branch is a bright core inside a soft glow, and the parts behind the front cool to a darker colour. See plasma channel and afterglow.

With Crack A into B on, as the page opens, it is an image transition between two pictures, A and B. See picture A and picture B. Picture B opens in torn bands along the lit branches, and the whole frame turns to B at the end. See burn reveal.

One number, the transition progress, runs from 0 to 1 over the strike, and an easing curve sets how it speeds up and slows down.

Six presets set every control at once: Crimson strike, Fern creep, Storm fork, Gold crack, Static lace and Blue flashover. You can swap in your own two pictures, and keep a PNG or a video.

Open Lightning reveal Start here

In this guide

  1. StartWhat you need and your first strike in five steps.
  2. Every controlEvery control in the panel, one line each.
  3. Three looksThree presets caught mid-strike, and how each was made.
  4. Keep your workThe PNG and the video.
  5. HelpWhat to do when something goes wrong.

It runs in your browser with WebGL. Your pictures stay on your device and nothing is uploaded. A mouse, a trackpad, a pen and a finger all work.