Lift

import {
  chord,
  defineCue,
  gain,
  lowPass,
  mix,
  normalize,
  note,
  pad,
  sequence,
  shape,
  sine,
  step,
  triangle,
  type CueDefinition,
} from "odori";

export type BedLiftOptions = {
  /** Tempo of the shimmer. Faster reads brighter, not louder. */
  bpm?: number;
  /** Root of the held chord, as a note name. */
  root?: string;
  /** Peak level before the mix normalizes the whole track. */
  peak?: number;
};

/**
 * Four bars with somewhere to be: a major add9 held underneath and a quiet
 * arpeggio circling above it on the eighths. The shimmer is the point — it
 * gives a cut forward motion without a drum in sight — and it stays quiet
 * enough that it colours the bed rather than performing over it.
 *
 * The brightest voice is low passed just above a kilohertz, so the motion is
 * felt more than heard and the voice keeps the range it needs.
 */
export const bedLift = ({bpm = 96, root = "c3", peak = 0.55}: BedLiftOptions = {}): CueDefinition => {
  const beat = step(bpm, 4);
  const bars = 4;
  const samples = beat * 4 * bars;

  const tones = chord(root, "add9");
  // The circling order: root, fifth, third, ninth. Up and never quite back.
  const circle = [0, 2, 1, 3];

  return defineCue({
    name: "bed.lift",
    durationInFrames: Math.round((samples / 48000) * 30),
    loops: true,
    params: {bpm, root, peak},
    render: () =>
      normalize(
        mix(
          // The held chord, warm and below everything.
          gain(lowPass(pad(tones, samples, {envelope: {attack: 1.4, sustain: 1, release: 1.4}}), 1000), 0.85),
          // The shimmer: one soft voice per eighth, an octave up, each gone
          // before the next arrives.
          lowPass(
            sequence(
              Array.from({length: 8 * bars}, (_, index) => ({
                at: index,
                play: (length: number) =>
                  shape(triangle(length, tones[circle[index % circle.length]] * 2), {
                    attack: 0.015,
                    decay: 0.32,
                    sustain: 0,
                    release: 0.08,
                  }),
                // The bar line leans in slightly, which is all the grid a bed needs.
                gain: index % 8 === 0 ? 0.2 : 0.12,
              })),
              {bpm, division: 8, samples},
            ),
            1600,
          ),
          // A floor under the root.
          gain(sine(samples, note(root) / 2), 0.22),
        ),
        peak,
      ),
  });
};

import {CueWave, defineComponentPreview} from "odori/preview";
import {bedLift, type BedLiftOptions} from "./bed-lift";

const Wave = ({bpm, root, peak}: BedLiftOptions) => <CueWave cue={bedLift({bpm, root, peak})} />;

export default defineComponentPreview({
  title: "Lift",
  category: "Sound/Beds",
  description: "A sustained chord with shimmering high notes.",
  component: Wave,
  canvas: {width: 1920, height: 1080, duration: "5s"},
  controls: {
    bpm: {type: "number", defaultValue: 96, min: 72, max: 128, step: 4},
    root: {type: "select", defaultValue: "c3", options: ["a2", "c3", "d3", "f3"]},
    peak: {type: "number", defaultValue: 0.55, min: 0.1, max: 1, step: 0.05},
  },
  examples: [{name: "Default", props: {}}, {name: "Slower", props: {bpm: 80}}],
});

import {Scene, Video} from "odori";
import {BedLift} from "../components/bed-lift/bed-lift";

<Video>
  <Scene id="bed-lift" duration="10s">
    <BedLift />
  </Scene>
</Video>