Draw a curve across the canvas with your mouse or finger. The page reads it as a melody — vertical position is pitch, horizontal position is time — and snaps it to the scale you pick. Goes up = pitch goes up. Goes flat = note holds.
KEY
TEMPO · 96 BPM · 4 bars
VOICE
Click and drag (or touch and slide). Top of the canvas is high, bottom is low. Draw left to right.
What's behind the snap
The canvas covers two octaves of the selected scale (about 14 scale degrees for diatonic keys, 10 for pentatonic). When you draw, the stroke is sampled to 32 evenly-spaced points across its X span. Each point's Y is mapped to the nearest scale degree, then notes are extracted by collapsing consecutive same-degree samples into single sustained notes.
So a flat line plays one held note. A staircase plays a clean run. A wiggly line plays a busier melody. A vertical jump becomes a leap. Anything you draw stays in key because the snap quantizes every sample.
The whole thing is four bars (16 beats) wide. Bars are marked. Voices are synthesized — bell is a sine plus 2× and 4× partials with quick decay, vib is three slightly-detuned sines (chorused), reed is a triangle plus a softer sawtooth for breath.
Share button copies the canvas as a base-32 URL hash. Anyone who opens the link sees and hears the same shape.
