feat(static): client-side alteration engine (port of player.alteration/audio)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-30 07:25:24 -07:00
parent 7ef3e0ccc6
commit be13248bdd
3 changed files with 124 additions and 0 deletions
@@ -0,0 +1,51 @@
+"use strict";
+const test = require("node:test");
+const assert = require("node:assert/strict");
+const A = require("../static/alteration.js");
+
+const c = (o) => ({ visual: "on", audio: "off", left: 0, right: 0, dark: 0, light: 0, ...o });
+
+test("identity at zero knobs", () => {
+  const p = A.plan(c({}));
+  assert.equal(p.grade.tone, 0);
+  assert.equal(p.overlay.level, 0);
+  assert.equal(p.dream.strength, 0);
+  assert.equal(p.is_identity, true);
+});
+
+test("mood tone is signed (light - dark)/KNOB_MAX, clamped", () => {
+  assert.equal(A.plan(c({ light: 4 })).grade.tone, 1);     // full light
+  assert.equal(A.plan(c({ dark: 4 })).grade.tone, -1);     // full dark
+  assert.equal(A.plan(c({ light: 2 })).grade.tone, 0.5);
+});
+
+test("left drives overlay level + intensity; right drives dream + affect", () => {
+  const p = A.plan(c({ left: 2, right: 4 }));
+  assert.equal(p.overlay.level, 2);
+  assert.equal(p.overlay.intensity, 0.5);
+  assert.equal(p.dream.strength, 4);
+  assert.equal(p.dream.intensity, 1);
+  assert.equal(p.affect.strength, 4);
+  assert.equal(p.affect.intensity, 1);
+  assert.equal(p.is_identity, false);
+});
+
+test("renderAudio: off → null, no coupling", () => {
+  assert.deepEqual(A.renderAudio("off", "cosmos.mp3", "https://x/"),
+    { source: "off", url: null, altitude_coupled: false });
+});
+
+test("renderAudio: soundtrack → mediaBase audio url, coupled", () => {
+  assert.deepEqual(A.renderAudio("soundtrack", "cosmos.mp3", "https://x/"),
+    { source: "soundtrack", url: "https://x/audio/cosmos.mp3", altitude_coupled: true });
+  // no scale audio → null url but still coupled
+  assert.deepEqual(A.renderAudio("soundtrack", "", "https://x/"),
+    { source: "soundtrack", url: null, altitude_coupled: true });
+});
+
+test("alteration() composes plan + render with video.shown from visual", () => {
+  const r = A.alteration(c({ visual: "off", audio: "soundtrack", left: 1 }), "reef.mp3", "https://x/");
+  assert.equal(r.render.video.shown, false);
+  assert.equal(r.render.audio.url, "https://x/audio/reef.mp3");
+  assert.equal(r.plan.overlay.level, 1);
+});