Dither engine guide

Start

The tool opens with a sample picture already dithered: a grey circle fading to black, with a white disc, a light triangle and a dark box on it.

A current browser. Chrome, Edge, Firefox and Safari all draw it.
A picture, if you want your own. Any picture the browser can open works; it is always shrunk to the dot grid, so size does not matter much.

Open Dither engine. The sample is already there.
Press Image A to open a picture, or drop one on the frame. Or keep the sample; Try with sample brings it back.
Pick a method under Algorithm, then move Scale, Dot size and Threshold until the picture reads well.
With a mouse, move over the dots to push them, and click for a shockwave. With a finger, tap for a shockwave, and keep the finger down and slide it to push the dots.
Press Save PNG at the top of the panel to keep it as dither-engine.png.

With Invert on, as the page opens, the dots mark the dark parts of the picture. Turn it off and they mark the bright parts.
The line under Image shows how many dots there are, the frames per second, and the size of the dot grid.
The push settings and the shockwave settings are hidden at first. Press Advanced under View to show them.
Your picture is kept on this device, and every lab tool that takes a picture opens with it, until you press × on its tile.
On a phone the controls sit in a bar at the bottom of the screen. Tap the bar to open them.