MatrixParams

background: MatrixColor

Cell backdrop behind the rain, non-premultiplied.

birthRate: number

Drop spawn rate: how many new falling streams are born per second in each column. Higher values spawn drops frequently (a busy, dense downpour — drops overlap into near-continuous streams); lower values leave long gaps between drops (sparse, intermittent rain).

brightness: number

Overall gain on the rain brightness.

charAspect?: number

Character box aspect ratio (width / height). Omit to auto-measure it from the font (advance over em height).

color: MatrixTrailColor

Trail colour — the classic phosphor green. Pass an array of two or more MatrixColor stops for a gradient along each drop's trail (first at the head, last at the tail end), interpolated in OKLCH. Pair with tailFade: 0 to fade purely via the gradient.

contrast: number

Contrast of the source luminance, pivoting around mid-grey (0.5). 1 leaves the input unchanged; < 1 flattens it toward grey; > 1 deepens the split between dark and bright regions, so the picture reads more sharply through the rain.

font: string

CSS font family used to render the glyph atlas.

fontWeight: string | number

CSS font weight for the glyph atlas ("normal", "bold", 100–900).

glyphs?: MatrixGlyphs

Glyph pool rained down the columns, picked at random per cell. Defaults to MATRIX_GLYPHS. Baked into the atlas at init(); change it (or font / fontWeight) then call MatrixEffect.updateAtlas (or re-add the effect) to rebuild.

glyphSpeed: number

Glyph reshuffle rate in changes per second (0 = static glyphs).

grid: number | [number, number]

Cell size in CSS px. A single number is a square cell; a [width, height] tuple sets the axes independently. Glyphs keep their native aspect (contain-fitted), so a non-square cell letterboxes rather than stretching.

headColor: MatrixColor

Leading-glyph colour at the head of each stream (usually near-white).

invert: boolean

Flip the source luminance (rain shows through dark areas instead).

seed: number

Random seed for the rain pattern (per-column speed/phase and the glyph sequence). Any number; the same seed always reproduces the same pattern, so pin it (with VFX.setTime) for deterministic snapshots / visual regression tests. 0 is the default look.

speed: number

Base fall speed in cells per second. Per-column randomised ±50%.

tail: number

Trail length in cells (how far the trail extends behind the head).

tailFade: number

How much the trail dims toward its tail, in [0, 1]. 1 is the classic bright-head / dim-tail falloff; 0 keeps the whole trail at full brightness so you control the fade yourself via the colour gradient (e.g. a color stop fading to transparent or black).