Downpour

Digital rain for Resolume Arena and Avenue: columns of characters falling at their own speeds, each with a bright leading glyph and a trail fading out behind it. It comes as two plugins rather than one, because FFGL resolves a single entry point per binary. Downpour is a source that draws over its own background on its own layer. Downpour Over is an effect that draws the same rain over the clip it sits on, so the controls live with the footage instead of on a layer above it.

As far as the rain's concerned, an alphabet and a book are the same thing: a list of characters. The only question is whether it picks from them at random or reads them in order. Junk mode scatters katakana, hex, binary or ASCII. A built-in token grammar makes up something that reads as source code, which is a different problem from random characters, because at that speed what the eye reads as code is the density of punctuation, and prose has hardly any. Four public domain passages are built in, or you can type your own text or load any text file, and then the document plays out in order rather than being sampled from.

Every cell is a closed-form function of its column, its row and the host's clock. There's no simulation state anywhere: no feedback texture, no previous frame. A rain that advances one frame at a time runs at whatever frame rate the host is managing, and Resolume's frame rate drops when the show gets heavy. This one runs at the speed you asked for whether the host is holding 60fps or 20, looks identical at 720p and at 4K, and can be scrubbed to any point without playing what came before.

Fonts are found by walking the machine's own font folders, and whatever you pick is rasterised into the glyph atlas. The fallback is per character rather than per font, which is what makes offering the choice safe: pick a typeface with no katakana and you get your font for the Latin and the plugin's own drawn face for the katakana, instead of a grid of empty boxes. The drawn face only covers ASCII and katakana, though, so an accented letter your font hasn't got draws blank. The chosen family name is saved in the composition next to the menu position, because the same menu position means a different typeface on a machine with different fonts installed.

It's also available as OpenFX plugins for DaVinci Resolve, Vegas Pro, Nuke and Natron, with the generator and Downpour Over in one bundle, calling the same Rain.cpp the shader is measured against. OFX frame time drives the rain, so a frame rendered on its own is exactly what playback shows.