Paper and prints

The paper, or the glass

Under Sumi the substrate is washi; under Anod it is black glass with a phosphor grain, and the charge glows over it. The medium’s side — the switch, the substrate pages, the palettes — is the medium guide’s. This page is the paper and the prints.

Under the ink is procedural washi — mulberry-fibre noise and absorption grain, with paper roughness setting the fibre strength. The paper is screen-locked: fibres and grain are sampled in screen space, never through the deformed field, because paper is the stationary substrate. Ink moves; the sheet does not. (If fibres ever warp with a comb stroke or drift with a piano roll, that is a bug, not a feature.)

Three built-in palettes per medium — Sumi black, Indigo, Ochre; Electric blue, Plasma orange, Phosphor green — and a custom slot with a library behind it, chosen on the Palette page; the per-drop hue selector (CC 74 in its default routing, or the palette-morph CC) shifts individual drops within the palette. The Substrate page sets the paper’s tint (cream, white, custom), its roughness and the fibre scale — or the glass’s darkness, grain and glow. The picture is rendered in linear light and encoded to sRGB identically on every backend, so a print matches the screen bit for bit in tone. Palettes →

A fresh sheet: the paper dip

Paper dip resets the tray to plain water. It is a settings action on every platform — the first control of the sheet on Android, Canvas on the desktop and the iPad, Paper dip in the web panel — never a MIDI message: the sustain pedal is a musical control in every mode and goes to your synth. Dip as often as you like: every dip lands in the prints ledger with the field it printed. The dip also re-bases the drop counter that drives hues, so a long session never runs the half-float palette selector out of precision. A recording begins with a dip.

Saving a print

Every dip of the session is in the Prints page — the ledger — with a thumbnail, its time, and the field it printed, so any of them re-exports at any size while the session lives: Export size (the screen’s, or larger — the field is resolution-independent), Export PNG, and under Anod Anod over alpha, the glow and the grid over a transparent background. The ledger is memory-capped, the oldest entries going first. Save the newest print writes the last dip’s print at the screen’s size — on the desktop to the Print folder (Save last print as PNG), on the iPad to Photos, on Android to the gallery, on the web as a download. What is in a print:

• the ink exactly as the field holds it — at the simulation resolution for a saved print, at the chosen size for an export — with the washi paper (or the glass and the glow) composited under it;
• not the orbit trace’s scope and not the fingering overlays: they are screen-locked drawings over the water, like the lattice;
• a PNG, always — 8 bits per channel, over alpha under Anod on request. A 16-bit TIFF for print workflows is not built; it waits on a demand that has not come;
• not the live ripple shimmer — with the ripple in live mode the sampling coordinate ripples on screen but the print samples the un-rippled field. The print is what touched the water; the shimmer is surface motion. In bake mode the ripple is real ink displacement and is in the print.

Resolution and performance

The simulation resolution is decoupled from the screen: Full-resolution simulation runs the field at the framebuffer’s size; off, it runs at a fraction (0.75 on phones and smaller tablets) and upsamples. Android drops to 0.6 under severe thermal pressure and recovers. Fields are RGBA16F everywhere — the parity form of the ink phase is what lets half floats survive a thousand drops without speckling.