Hex

A hex color is an sRGB triple encoded as three or four bytes in hexadecimal.

Syntax

iridis accepts two forms:

Form	Bytes	Channels
#rrggbb	3	red, green, blue
#rrggbbaa	4	red, green, blue, alpha

The leading # is optional in user input but the canonical stored form keeps it. Each byte ranges 00-ff (0-255). Case is normalised to lower-case on storage.

The three-digit shorthand #rgb and the four-digit #rgba are not accepted. Anything other than six or eight hexadecimal characters after the optional # is rejected.

Conversion

A hex string converts to floating-point sRGB by reading each byte and dividing by 255. Alpha follows the same rule when present, otherwise defaults to 1.

r = parseInt(hex[0:2], 16) / 255
g = parseInt(hex[2:4], 16) / 255
b = parseInt(hex[4:6], 16) / 255
a = hex.length === 8 ? parseInt(hex[6:8], 16) / 255 : 1

The reverse direction multiplies each channel by 255, rounds, and pads to two hexadecimal digits. The canonical hex written back from a ColorRecord is always six digits, alpha lives in the alpha field, not in the hex string.

Math primitives

Primitive	File	Behaviour
hexToRgb	packages/core/src/math/HexToRgb.ts	parses a hex string and returns a full ColorRecord via ColorRecordFactory.fromHex
rgbToHex	packages/core/src/math/RgbToHex.ts	writes three sRGB channels as #rrggbb

ColorRecordFactory.fromHex (packages/core/src/math/ColorRecordFactory.ts) holds the validation regex ^[0-9a-fA-F]{6}([0-9a-fA-F]{2})?$ and the alpha extraction logic. It populates the OKLCH coordinates by routing the parsed sRGB through the same path fromRgb uses, so a record built from hex is interchangeable with one built from any other intake.

Where it appears

• intake:hex (packages/core/src/tasks/intake/IntakeHex.ts) consumes hex strings from input.colors and produces ColorRecord entries.
• intake:any dispatches hex inputs to intake:hex.
• emit:cssVars and the stylesheet plugin write hex back out as the default serialised form.
• The visual picker (docs/.vitepress/theme/components/IridisPicker.vue) round-trips hex on every edit through HSV → RGB → hex.