Sound-reactive shapes

Mono amplitude shifts the scalar threshold — the marcher renders a different isosurface of the same field. For closed shapes (sphere, box, torus, Platonic solids) this expands the surface outward uniformly. For open surfaces (paraboloid, saddle, hyperboloid) it translates the surface along the field gradient — the sheet moves rather than inflates.

Left channel compresses the Y axis; right channel expands X and Z. Width and height each have their own slider, so the effect can be made very drastic independently on each axis.

A hash function assigns each surface point a fixed random displacement, creating a spiky silhouette that reacts to mono amplitude. Lighting uses the smooth base-surface normal rather than the displaced one: the rim term follows the original curvature, so the glowing corona tracks the clean outline of the shape while the spiky geometry defines its edge.

The bottom of the shape samples the current frame; the top samples the oldest. Amplitude pulses appear at the base and travel upward as time passes.

The centre samples the current amplitude; the outer surface samples the oldest. A beat inflates the centre first, then the effect spreads outward as a concentric pressure wave.

Each horizontal slice rotates by the amplitude at the corresponding historical moment. The angle slider controls maximum rotation. The twist axis defaults to vertical but can be tilted in X and Z — tilting toward horizontal turns the corkscrew into a side-roll.

Vertical position on the shape maps continuously to a frequency bin. Each height level inflates laterally by the energy in that bin — sub-bass bows the equator out, high partials flare the top. The shape becomes a 3D equaliser display.

N evenly-spaced frequency bands (2–8, set by the Bands slider) are mapped to N positions along the shape's height. A Catmull-Rom spline connects them, giving a smooth C1-continuous deformation curve. The curve value at each surface point drives a radial outward displacement along the surface normal. With 2 bands the bottom responds to sub-bass and the top to treble; adding more bands gives finer spectral resolution.

Two pairs of frequency bands drive opposing shear deformations on different axes: sub-bass vs. top treble tilt one axis, low-mid vs. upper-mid tilt the other. When spectral energy is balanced the shape stands upright; imbalance leans it. A heavy low end tilts the shape one way, a high-heavy mix the other. The shear axes rotate slowly over time so the lean direction changes rather than always pointing the same way.

A cylinder whose cross-section at every height is the frequency spectrum in polar form — azimuthal angle maps to an FFT bin, radius equals that bin's energy. The spectrum is extruded vertically into a column.

Eight FFT bands each weight a standing wave along a distinct 3D direction, distributed uniformly using a golden-angle spiral. The shape is the isosurface of their interference sum, restructuring as spectral content shifts.

A horizontal cylinder; position along its long axis maps to frequency, azimuthal angle around the cross-section maps to time. The full 2D spectrogram wraps around the drum surface. Rotates around its own axis.

Two vertical tubes side by side — left carries the L-channel FFT, right carries the R-channel. Each tube's radius at a given height equals the energy at the corresponding frequency bin for that channel.

Two surfaces of revolution side by side: left driven by the L-channel amplitude history, right by the R-channel. Height encodes time; a beat imprints a bulge that travels upward as the frame advances.

Seven tori arranged horizontally, each tuned to one mel-band. The major radius of each ring scales with the energy in its band. Rotates around its own axis.

Tip points toward the camera; the cone widens toward the back. Azimuthal angle encodes frequency, position along the cone's axis encodes time. A slow bilateral wiggle reveals different azimuthal slices.

A height map tilted toward the camera: horizontal position encodes frequency, vertical position encodes time, and depth encodes spectral amplitude. The full spectrogram becomes a 3D landscape.

A four-coil helix where each segment's tube radius equals the FFT amplitude at the corresponding frequency. Constant one-directional rotation creates the barber-pole illusion of a signal climbing endlessly upward.

A horizontally elongated box where the shell thickness at each position along its length equals the magnitude of spectral change between the current frame and 48 frames prior. Frequencies that shifted most protrude furthest from the surface.