OBSERVATION 034
鰯玉
Iwashidama — Bait Ball
Press the picture or the button to reduce the points.40,000 → 625 → 40 → 1, then back to 40,000.
At fewer points, dots grow and trails linger to help you follow their paths.
“Listen” maps the displayed points to sound.Changing the count rebuilds the sound.
Two thousand small fish have become one sphere.
Nobody designed the sphere.
Each fish only rides the current beside it.
There is a fast layer and a slow one, and the ball swells and shrinks as if breathing.
From time to time the school splits open.
The fish at the opening run outward, and when something has passed, it closes again.
What is in there is not recorded here.
Every one of the forty thousand points belongs to the side that fled.
The shape of what is not recorded remains only in the way they avoided it.
Reduce the points and the fish go first, leaving the shell of the sphere.
At forty the shell comes apart into short drifting curls.
At one, what is left is a single path circling where the sphere was.
You cannot avoid something that is not there.
That something was avoided — the way of avoiding remembers that.
Read and verify the equation
(i, t,
j = i / 20 | 0, k = (i % 20) / 19,
u = j * .618034 % 1, v = j * .754878 % 1, w2 = j * .414214 % 1,
y0 = 2 * u - 1, rr = sqrt(max(0, 1 - y0 * y0)), sp = j % 2 ? .5 : .25,
A = v * TAU + t * sp + .3 * sin(y0 * 4 + t * .5),
R = 104 + 9 * sin(t * .5 + w2 * TAU),
x0 = R * rr * cos(A), z0 = R * rr * sin(A), Y0 = R * y0 * .92,
Px = 96 * cos(t * .25 + 2.1), Py = 44 * sin(t * .5), Pz = 96 * sin(t * .25 + 2.1),
dx = x0 - Px, dy = Y0 - Py, dz = z0 - Pz, q = dx * dx + dy * dy + dz * dz,
s = sqrt(q), M = 92 * exp(0 - q / 3600) / (s + 4) * (1 + .5 * k),
tx = 0 - sin(A), tz = cos(A), L = 8 + 3 * w2,
X = x0 + dx * M + tx * L * (k - .5), Z = z0 + dz * M + tz * L * (k - .5),
Y = Y0 + dy * M + 1.2 * (i * .324717 % 1 - .5),
Dx = 200 + 14 * sin(t * .25 + .7) + 6 * sin(t * .5 + 3.1),
Dy = 200 + 11 * cos(t * .25 + 2.9) + 5 * sin(t * .75 + .7)
) => [Dx + (X + .3 * Z) * .72, Dy + (Y - .35 * Z) * .72]
Fingerprint of this equation
sha256:fcb39ebae71f0fade7b815c843af9f6b7ec1af5e17815d02a9c9b5e441020ca8
The same point number and time give the same coordinates.
Trails and the appearance of points depend on rendering settings and the device.
The button above takes the equation out as it is. To count it again yourself:
pbpaste > f.txt && printf %s "$(cat f.txt)" | shasum -a 256
Take it and run it.What appears when you change the equation? Run and rewrite this equation →