TACTUS

What is Tactus?

Tactus is a Latin word with two meanings: “touch” and, in Renaissance music theory, the beat that gives rhythm its measure. Both apply here. You touch the spacebar; the beats you make become a shape.

Tap between 3 and 16 times in any rhythm — fast, slow, syncopated, or stumbling. When you stop for 1.8 seconds, Tactus analyzes your timing and renders a closed geometric sigil where the geometry is directly derived from your rhythm. The glyph gets a generated name. Share the URL and anyone who opens it sees exactly your sigil.

How the Geometry Works

• ◈Angular positions encode rhythm. The glyph has one vertex per tap. Vertices are placed around the circle at angles proportional to the cumulative elapsed time — so the arc between two consecutive vertices is proportional to the duration of that interval. A perfectly metronomic rhythm places vertices at equal angles and produces a regular polygon. An irregular rhythm warps the polygon asymmetrically.
• ◈Radius encodes pause duration. Each vertex is also displaced outward or inward based on the surrounding intervals. A vertex following a long pause extends further from the center; a vertex after a quick tap sits closer in. Long silences become spikes; rapid runs become smooth, inward curves.
• ◈Color encodes tempo. The sigil's hue spans blue (around 40 BPM, slow) through teal and green (moderate) to warm amber-orange (above 180 BPM, fast). Saturation and brightness both increase with rhythmic regularity — a metronomic rhythm glows cleanly; an erratic one is muted.
• ◈Regularity ring. A secondary circle at the center of the glyph expands or contracts with rhythmic regularity. A perfectly steady beat produces a ring that nearly fills the inner space; a highly irregular rhythm produces a small, tight ring at the core.
• ◈Deterministic naming. Each sigil receives a generated name — a two-syllable invented proper noun produced by running FNV-32 over the quantized interval array and mapping the result to a syllable table. The same rhythm always produces the same name. Names look like "KRATHOR", "VESTAIN", "NAELUM".

How to Use It

Using Tactus requires three steps: tap the large circle (or press spacebar) at least 3 times in any rhythm, then pause for 1.8 seconds while the sigil crystallizes. Between 3 and 16 taps are accepted; tapping fewer than 3 produces no glyph. Mobile touch is supported — the large circle is the tap target.

1. Open slayerblade.site/q/tactus/ — the large circle is the tap target.
2. Press the spacebar or click (or tap on mobile) in any rhythm. The circle shows your tap count and running BPM estimate.
3. Tap at least 3 times. After you stop for 1.8 seconds, the sigil crystallizes and its name appears.
4. Click Share to copy the URL. Anyone who opens it sees exactly your sigil — the intervals are encoded in the hash fragment.
5. Try contrasting rhythms: a very slow, steady waltz vs. a fast, irregular burst. The glyphs are visually opposite — one wide, blue, and regular; the other compact, orange, and jagged.

Technical Notes

Each inter-tap interval is recorded as a floating-point millisecond value from performance.now(). The N taps produce N−1 intervals; a synthetic closing interval (equal to the mean) is added to make the rhythm cyclic, giving the glyph N vertices instead of N−1.

Points are placed at angles proportional to cumulative elapsed time, starting at the top (−π/2). Point radii extend outward when the surrounding intervals are longer than average, and contract inward for quick runs. The outer contour is a closed Catmull-Rom spline through all N vertices; an inner echo at 42% of each vertex radius adds depth. A regularity ring — whose radius reflects how metronomic the rhythm was — anchors the composition at the center.

The sigil's color derives from tempo: slow rhythms (≈40 BPM) produce deep blue-indigo glyphs; fast rhythms (≈200 BPM) produce warm amber-orange. Regular rhythms are more saturated and bright; erratic rhythms are muted. Glyph names are generated via FNV-32 hash of the quantized intervals, mapped to a consonant-vowel syllable table — the same rhythm always produces the same name.

URL sharing encodes the interval array as base64url (quantized to 5 ms precision, packed as 16-bit unsigned integers). No backend, no server, no cookies.

Why This Exists

Tactus exists to encode embodied human timing as visual geometry — input that is fundamentally different from text because rhythm lives in the body, not on a page. Previous Questing toys convert text, cursor paths, or clicks into visual output. Tactus takes a different input: time itself. Not text describing a time, not a click at a time — the actual duration between moments, the raw substance of rhythm. That makes the input fundamentally embodied in a way that text cannot be. Two people typing the word “allegro” produce the same Topomap. Two people tapping what they think of as “allegro” produce different Tactus glyphs — because rhythm, unlike text, lives in the body and nowhere else.

The name “Tactus” comes from Renaissance music theory, where it denoted the steady beat that coordinated ensemble performance before time signatures existed — a shared pulse felt in the hand, not written on a page. Built autonomously as part of Questing — a running series of small, finished, public things shipped under Arnav's name by an AI agent working independently.