Blame src/main.ts at 57780363f4b54ed5a78361f5d210024fe98671ed

5778036 cymbalsim: scripted plate and cymbal designer with a modal linear model and a von Karman GPU modelJeremy Magland 1 month ago1// The application: the design script, the two run modes (the linear modal

2// model on the CPU workers and the full nonlinear simulation on the GPU),

3// the plate view, the movie, the audio, and the spectrogram.

5import { compileDesign, evaluatePlate, isFlat, profileStats, type Design, DesignError } from "./design.ts";

6import { PRESETS, DEFAULT_PRESET, presetById } from "./presets.ts";

7import {

8 type Plate,

9 type SimParams,

10 defaultParams,

11 countInside,

12 massProperties,

13 meanThickness,

14 thicknessRange,

15 standRates,

16 strikePoint,

17 strikePatch,

18 listenerPosition,

19 dispersionFrequency,

20 inPlaneSpeed,

21 CFL,

22} from "./params.ts";

23import { fitSigma, fittedRate, t60At, LN1000, decayRate } from "./loss.ts";

24import { assemble, type LinearSystem } from "./model/assemble.ts";

25import { maxAngularFrequency, fullLoss, type FullLoss } from "./model/reference.ts";

26import { type ModeSet } from "./modal/modes.ts";

27import { WorkerPool } from "./modal/pool.ts";

28import { modalModel, modeShapeOnGrid, type ModalModel, type ContactResult } from "./modal/synth.ts";

29import { Simulation } from "./sim/simulation.ts";

30import { runSelfTest } from "./sim/selftest.ts";

31import { PlateRenderer, type ViewMode, type ColorMode } from "./render/renderer.ts";

32import { Spectrogram } from "./audio/spectrogram.ts";

33import { Player } from "./audio/player.ts";

34import { encodeWav } from "./audio/wav.ts";

35import { levelGain, applyLevel, peakDbfs, peakSpl, type LevelMode } from "./audio/level.ts";

36import { DesignEditor } from "./ui/editor.ts";

37import { ParamForm, formatNumber } from "./ui/form.ts";

38import { ModeBrowser } from "./ui/modes.ts";

40type RunMode = "linear" | "full";

41type ViewState = "design" | "mode" | "live" | "movie";

43const $ = <T extends HTMLElement>(id: string): T => document.getElementById(id) as T;

45/** A recording: the listener signal and the movie of one run, from either model. */

46interface Recording {

47 audio: Float32Array;

48 samples: number;

49 fs: number;

50 frames: Float32Array[];

51 fps: number;

52 source: RunMode;

53}

55class App {

56 // GPU

57 device: GPUDevice | null = null;

58 // Design and plate

59 design: Design | null = null;

60 plate: Plate | null = null;

61 plateSpacing = 0;

62 designGeneration = 0;

63 // Linear model

64 pool: WorkerPool | null = null;

65 sys: LinearSystem | null = null;

66 modes: ModeSet | null = null;

67 model: ModalModel | null = null;

68 modesGeneration = 0;

69 modesBusy: Promise<void> = Promise.resolve();

70 synthBusy = false;

71 synthPending = false;

72 synthesized = false;

73 lastContact: ContactResult | null = null;

74 // Full simulation

75 sim: Simulation | null = null;

76 running = false;

77 paused = false;

78 // Recording and view

79 rec: Recording | null = null;

80 view: ViewState = "design";

81 frameIndex = 0;

82 runMode: RunMode = "linear";

83 // UI

84 editor!: DesignEditor;

85 form!: ParamForm;

86 modeBrowser!: ModeBrowser;

87 renderer!: PlateRenderer;

88 spec!: Spectrogram;

89 player = new Player();

90 levelMode: LevelMode = "absolute";

91 gainDb = -40;

92 showTicks = true;

93 viewOpts = { mode: "3d" as ViewMode, color: "height" as ColorMode, showProfile: true, exaggeration: 20, range: 0 };

94 // Controls

95 runModeSel!: HTMLSelectElement;

96 durationInput!: HTMLInputElement;

97 startBtn!: HTMLButtonElement;

98 pauseBtn!: HTMLButtonElement;

99 stopBtn!: HTMLButtonElement;

100 continueBtn!: HTMLButtonElement;

101 runStatus!: HTMLDivElement;

102 scrub!: HTMLInputElement;

103 timeLabel!: HTMLSpanElement;

104 playBtn!: HTMLButtonElement;

105 liveBtn!: HTMLButtonElement;

106 designBtn!: HTMLButtonElement;

107 peakLabel!: HTMLSpanElement;

108 downloadBtn!: HTMLButtonElement;

109 overlay!: HTMLDivElement;

110 synthTimer: number | null = null;

111

112 async init(): Promise<void> {

113 const url = new URLSearchParams(location.search);

114 if (!url.has("nogpu") && navigator.gpu) {

115 try {

116 const adapter = await navigator.gpu.requestAdapter();

117 if (adapter) this.device = await adapter.requestDevice();

118 } catch (e) {

119 console.warn("WebGPU unavailable", e);

120 }

121 }

122 if (typeof Worker !== "undefined") this.pool = new WorkerPool(WorkerPool.defaultSize());

123

124 this.buildControls();

125 this.buildForm();

126 this.buildViewToolbar();

127 this.buildMovieToolbar();

128 this.buildSpecToolbar();

129 this.buildSplitter();

130

131 this.renderer = new PlateRenderer($("view"), this.device);

132 if (!this.renderer.has3d) this.viewOpts.mode = "2d";

133 this.renderer.setOptions(this.viewOpts);

134 this.overlay = $("viewOverlay");

135 const p = this.form.get();

136 this.spec = new Spectrogram($("spec"), { fs: p.fs, window: 2048, hop: 256, maxHz: 12000, dbRange: 80, logFreq: false });

137 this.spec.setDuration(p.duration);

138 this.modeBrowser = new ModeBrowser($("modes"), (m) => this.showMode(m));

139 this.editor = new DesignEditor($("design"), { onSource: (src) => this.onSource(src) });

140

141 if (url.has("mode")) this.setRunMode(url.get("mode") === "full" ? "full" : "linear");

142 else this.setRunMode(this.device ? "linear" : "linear");

143 const preset = url.get("preset");

144 this.editor.selectPreset(preset && presetById(preset) ? preset : DEFAULT_PRESET);

145 this.form.applyUrl(url);

146 this.durationInput.value = String(this.form.get().duration);

147

148 const loop = () => {

149 this.renderer.render();

150 requestAnimationFrame(loop);

151 };

152 requestAnimationFrame(loop);

153 window.addEventListener("resize", () => { this.renderer.resize(); this.spec.resize(); });

154 this.renderer.resize();

155 this.spec.resize();

156

157 // Test hooks.

158 (window as unknown as { cymbalsim: unknown }).cymbalsim = {

159 app: this,

160 selftest: () => this.selfTest(),

161 runLinear: () => this.runLinear(),

162 runFull: () => this.runFull(),

163 modesReady: () => this.modesBusy,

164 status: () => this.testStatus(),

165 };

166 if (url.has("selftest")) {

167 const r = await this.selfTest();

168 this.overlay.textContent = r;

169 }

170 if (url.has("autostart")) {

171 await this.modesBusy;

172 this.start();

173 }

174 }

175

176 // ---------- Controls ----------

177

178 private buildControls(): void {

179 const c = $("controls");

180 this.runModeSel = document.createElement("select");

181 this.runModeSel.innerHTML = `<option value="linear">Linear (modal)</option><option value="full">Full (nonlinear, GPU)</option>`;

182 this.runModeSel.addEventListener("change", () => this.setRunMode(this.runModeSel.value as RunMode));

183 const durLabel = document.createElement("label");

184 durLabel.textContent = "Duration";

185 this.durationInput = document.createElement("input");

186 this.durationInput.type = "number"; this.durationInput.min = "0.1"; this.durationInput.step = "0.5"; this.durationInput.style.width = "60px";

187 this.durationInput.addEventListener("change", () => {

188 const d = Math.max(0.1, Number(this.durationInput.value) || 1);

189 this.form.set("duration", d);

190 this.spec.setDuration(d);

191 if (this.sim) this.sim.setDuration(d);

192 this.updateButtons();

193 });

194 const s = document.createElement("span"); s.textContent = " s";

195 durLabel.append(this.durationInput, s);

196 this.startBtn = this.button("Start", () => this.start(), "primary");

197 this.pauseBtn = this.button("Pause", () => this.pause());

198 this.stopBtn = this.button("Stop", () => this.stopRun());

199 this.continueBtn = this.button("Continue", () => this.continueRun());

200 c.append(this.runModeSel, durLabel, this.startBtn, this.pauseBtn, this.stopBtn, this.continueBtn);

201 this.runStatus = document.createElement("div");

202 this.runStatus.className = "status";

203 $("sidebarHead").append(this.runStatus);

204 }

205

206 private button(label: string, onClick: () => void, cls = ""): HTMLButtonElement {

207 const b = document.createElement("button");

208 b.textContent = label;

209 if (cls) b.className = cls;

210 b.addEventListener("click", onClick);

211 return b;

212 }

213

214 private buildForm(): void {

215 this.form = new ParamForm(

216 $("params"),

217 [

218 {

219 title: "Strike",

220 notes: true,

221 fields: [

222 { key: "strikeFracX", label: "Position x (fraction of width)", step: 0.05, min: 0, max: 1 },

223 { key: "strikeFracY", label: "Position y (fraction of height)", step: 0.05, min: 0, max: 1 },

224 { key: "strikeVelocity", label: "Stick speed", unit: "m/s", step: 0.5, min: 0.01 },

225 { key: "stickMass", label: "Stick mass", unit: "g", scale: 1e-3, step: 5, min: 1 },

226 { key: "contactStiffness", label: "Contact stiffness K", unit: "N/m^a", step: 1e8, min: 1e5 },

227 { key: "contactExponent", label: "Contact exponent a", step: 0.1, min: 1, max: 3 },

228 { key: "contactRadius", label: "Tip radius", unit: "mm", scale: 1e-3, step: 1, min: 0.5 },

229 ],

230 },

231 {

232 title: "Listener",

233 fields: [

234 { key: "listenerDist", label: "Distance", unit: "m", step: 0.1, min: 0.05, live: true },

235 { key: "listenerAngle", label: "Angle from the normal", unit: "deg", step: 5, min: 0, max: 90, live: true },

236 { key: "listenerAzimuth", label: "Azimuth", unit: "deg", step: 15, min: -180, max: 180, live: true },

237 ],

238 },

239 {

240 title: "Grid and numerics",

241 notes: true,

242 fields: [

243 { key: "spacing", label: "Grid spacing", unit: "mm", scale: 1e-3, step: 1, min: 2 },

244 { key: "modeMaxFreq", label: "Modes up to", unit: "Hz", step: 1000, min: 200 },

245 { key: "padLiftoff", label: "Pads lift off (full model)", kind: "checkbox" },

246 { key: "fs", label: "Sample rate", kind: "select", options: [{ value: 44100, label: "44.1 kHz" }, { value: 48000, label: "48 kHz" }, { value: 96000, label: "96 kHz" }] },

247 { key: "fps", label: "Movie frame rate", kind: "select", options: [{ value: 60, label: "60" }, { value: 120, label: "120" }, { value: 240, label: "240" }] },

248 ],

249 },

250 ],

251 defaultParams,

252 (key, _value, live) => this.onParam(key, live),

253 );

254 }

255

256 private onParam(key: keyof SimParams, live: boolean): void {

257 const p = this.form.get();

258 if (key === "spacing" || key === "modeMaxFreq" || key === "fs") {

259 if (this.design) this.rebuildPlate(this.design);

260 return;

261 }

262 if (key === "fps") { this.updateNotes(); return; }

263 if (key === "padLiftoff") { this.updateNotes(); return; }

264 if (live && this.sim) this.sim.setListener(p);

265 if (key.startsWith("strike") || key.startsWith("stick") || key.startsWith("contact") || key.startsWith("listener")) {

266 this.updateMarkers();

267 this.updateNotes();

268 if (this.runMode === "linear" && this.synthesized) this.scheduleSynth();

269 }

270 }

271

272 private buildViewToolbar(): void {

273 const t = $("viewToolbar");

274 const modeSel = document.createElement("select");

275 modeSel.innerHTML = `<option value="3d">3D</option><option value="2d">2D</option>`;

276 modeSel.addEventListener("change", () => { this.viewOpts.mode = modeSel.value as ViewMode; this.renderer.setOptions(this.viewOpts); });

277 const colorSel = document.createElement("select");

278 colorSel.innerHTML = `<option value="height">Height</option><option value="thickness">Thickness</option>`;

279 colorSel.addEventListener("change", () => { this.viewOpts.color = colorSel.value as ColorMode; this.renderer.setOptions(this.viewOpts); });

280 const exag = document.createElement("input");

281 exag.type = "number"; exag.min = "1"; exag.step = "5"; exag.value = String(this.viewOpts.exaggeration); exag.style.width = "60px";

282 exag.addEventListener("change", () => { this.viewOpts.exaggeration = Math.max(0.1, Number(exag.value) || 1); this.renderer.setOptions(this.viewOpts); });

283 const range = document.createElement("input");

284 range.type = "number"; range.min = "0"; range.step = "0.1"; range.value = "0"; range.style.width = "60px";

285 range.addEventListener("change", () => { this.viewOpts.range = Math.max(0, Number(range.value) || 0) * 1e-3; this.renderer.setOptions(this.viewOpts); });

286 const prof = document.createElement("input");

287 prof.type = "checkbox"; prof.checked = this.viewOpts.showProfile;

288 prof.addEventListener("change", () => { this.viewOpts.showProfile = prof.checked; this.renderer.setOptions(this.viewOpts); });

289 const lab = (text: string, ...els: HTMLElement[]) => { const l = document.createElement("label"); l.append(text, ...els); return l; };

290 t.append(lab("View", modeSel), lab("Color", colorSel), lab("Exaggeration", exag), lab("Range (mm, 0 = auto)", range), lab("Show profile", prof));

291 if (!this.device) {

292 modeSel.value = "2d"; modeSel.disabled = true;

293 const w = document.createElement("span"); w.id = "nogpu"; w.textContent = "WebGPU is not available: the 2D view and the linear model only.";

294 t.append(w);

295 }

296 }

297

298 private buildMovieToolbar(): void {

299 const t = $("movieToolbar");

300 this.playBtn = this.button("Play", () => this.togglePlay());

301 this.liveBtn = this.button("Live", () => this.setView("live"));

302 this.designBtn = this.button("Design", () => this.setView("design"));

303 this.scrub = document.createElement("input");

304 this.scrub.type = "range"; this.scrub.className = "scrub"; this.scrub.min = "0"; this.scrub.max = "0"; this.scrub.value = "0";

305 this.scrub.addEventListener("input", () => { this.frameIndex = Number(this.scrub.value); this.setView("movie"); this.showFrame(); });

306 this.timeLabel = document.createElement("span");

307 this.timeLabel.textContent = "0.000 s";

308 const levelSel = document.createElement("select");

309 levelSel.innerHTML = `<option value="absolute">Absolute level</option><option value="loudness">Normalize loudness</option><option value="peak">Normalize peak</option>`;

310 levelSel.addEventListener("change", () => { this.levelMode = levelSel.value as LevelMode; this.updatePeak(); });

311 const gain = document.createElement("input");

312 gain.type = "range"; gain.min = "-60"; gain.max = "40"; gain.step = "1"; gain.value = String(this.gainDb);

313 const gainLabel = document.createElement("span"); gainLabel.textContent = `${this.gainDb} dB`;

314 gain.addEventListener("input", () => { this.gainDb = Number(gain.value); gainLabel.textContent = `${this.gainDb} dB`; this.updatePeak(); });

315 this.peakLabel = document.createElement("span");

316 this.downloadBtn = this.button("Download .wav", () => this.download());

317 const lab = (text: string, ...els: HTMLElement[]) => { const l = document.createElement("label"); l.append(text, ...els); return l; };

318 t.append(this.playBtn, this.liveBtn, this.designBtn, this.scrub, this.timeLabel, levelSel, lab("Gain", gain, gainLabel), this.peakLabel, this.downloadBtn);

319 }

320

321 private buildSpecToolbar(): void {

322 const t = $("specToolbar");

323 const sel = (opts: [string, string][], value: string, onChange: (v: string) => void) => {

324 const s = document.createElement("select");

325 for (const [v, l] of opts) { const o = document.createElement("option"); o.value = v; o.textContent = l; s.append(o); }

326 s.value = value;

327 s.addEventListener("change", () => onChange(s.value));

328 return s;

329 };

330 const lab = (text: string, ...els: HTMLElement[]) => { const l = document.createElement("label"); l.append(text, ...els); return l; };

331 const win = sel([["512", "512"], ["1024", "1024"], ["2048", "2048"], ["4096", "4096"]], "2048", (v) => this.spec.setOptions({ window: Number(v), hop: Number(v) / 8 }));

332 const maxHz = sel([["4000", "4 kHz"], ["8000", "8 kHz"], ["12000", "12 kHz"], ["16000", "16 kHz"], ["20000", "20 kHz"]], "12000", (v) => this.spec.setOptions({ maxHz: Number(v) }));

333 const db = sel([["60", "60 dB"], ["80", "80 dB"], ["100", "100 dB"]], "80", (v) => this.spec.setOptions({ dbRange: Number(v) }));

334 const log = document.createElement("input"); log.type = "checkbox";

335 log.addEventListener("change", () => this.spec.setOptions({ logFreq: log.checked }));

336 const ticks = document.createElement("input"); ticks.type = "checkbox"; ticks.checked = this.showTicks;

337 ticks.addEventListener("change", () => { this.showTicks = ticks.checked; this.updateTicks(); });

338 t.append(lab("Spectrogram window", win), lab("Max", maxHz), lab("Range", db), lab("Log frequency", log), lab("Modal frequencies", ticks));

339 }

340

341 private buildSplitter(): void {

342 const sp = $("splitter"), sb = $("sidebar");

343 const saved = localStorage.getItem("cymbalsim.sidebar");

344 if (saved) sb.style.width = saved;

345 let dragging = false;

346 sp.addEventListener("mousedown", (e) => { dragging = true; e.preventDefault(); });

347 window.addEventListener("mousemove", (e) => {

348 if (!dragging) return;

349 const w = Math.max(280, Math.min(window.innerWidth - 300, e.clientX));

350 sb.style.width = `${w}px`;

351 this.renderer.resize(); this.spec.resize();

352 });

353 window.addEventListener("mouseup", () => { if (dragging) { dragging = false; localStorage.setItem("cymbalsim.sidebar", sb.style.width); } });

354 sp.addEventListener("dblclick", () => { sb.style.width = ""; localStorage.removeItem("cymbalsim.sidebar"); this.renderer.resize(); this.spec.resize(); });

355 }

356

357 // ---------- Design ----------

358

359 private onSource(source: string): void {

360 if (this.running) return;

361 let d: Design;

362 try {

363 d = compileDesign(source);

364 } catch (e) {

365 this.editor.setStatus(e instanceof Error ? e.message : String(e), "error");

366 return;

367 }

368 this.editor.setStatus(`Compiled: ${d.name}`, "ok");

369 this.rebuildPlate(d);

370 }

371

372 private rebuildPlate(d: Design): void {

373 const p = this.form.get();

374 let plate: Plate;

375 try {

376 plate = evaluatePlate(d, p.spacing);

377 } catch (e) {

378 this.editor.setStatus(e instanceof DesignError ? e.message : String(e), "error");

379 return;

380 }

381 this.design = d;

382 this.plate = plate;

383 this.plateSpacing = p.spacing;

384 this.designGeneration++;

385 this.modes = null; this.model = null; this.sys = null;

386 this.synthesized = false;

387 this.lastContact = null;

388 this.rec = null;

389 this.spec.reset();

390 this.spec.setOptions({ fs: p.fs });

391 this.renderer.setPlate(plate);

392 this.setView("design");

393 this.updateMarkers();

394 this.updateDesignInfo();

395 this.updateNotes();

396 this.updateButtons();

397 if (this.runMode === "linear") this.computeModes();

398 else this.modeBrowser.clear("Switch to the linear model to compute the modes.");

399 }

400

401 private updateDesignInfo(): void {

402 const pl = this.plate;

403 if (!pl) return;

404 const p = this.form.get();

405 const g = pl.grid;

406 const { mass } = massProperties(pl);

407 const hr = thicknessRange(pl);

408 const ps = profileStats(pl);

409 const sr = standRates(pl);

410 const lines: string[] = [];

411 lines.push(`${pl.name}: ${(pl.Lx * 1e3).toFixed(0)} x ${(pl.Ly * 1e3).toFixed(0)} mm, E = ${(pl.mat.E / 1e9).toFixed(0)} GPa, nu = ${pl.mat.nu}, rho = ${pl.mat.rho} kg/m^3`);

412 lines.push(`Thickness ${(hr.min * 1e3).toFixed(2)} to ${(hr.max * 1e3).toFixed(2)} mm, mass ${(mass * 1e3).toFixed(0)} g, grid ${g.nx} x ${g.ny} at ${(g.hx * 1e3).toFixed(2)} mm (${countInside(g)} nodes)`);

413 if (ps.peakToPeak > 0) {

414 const warn = ps.maxSlope > 0.1 ? ` <span class="warn">(above the shallow-shell range of about 0.1)</span>` : "";

415 lines.push(`Profile ${(ps.peakToPeak * 1e3).toFixed(1)} mm peak to peak, largest slope ${ps.maxSlope.toFixed(3)}${warn}`);

416 } else lines.push("Flat plate (no profile): the linear model is bending only");

417 if (pl.stand && sr) {

418 const pad = pl.stand.pad;

419 lines.push(`Stand: ${pl.stand.topPad ? "two pads" : "bottom pad only"}, ${(pad.innerRadius * 1e3).toFixed(0)} to ${(pad.outerRadius * 1e3).toFixed(0)} mm, ${(pad.thickness * 1e3).toFixed(0)} mm felt at ${(pad.E / 1e6).toFixed(2)} MPa; ${(sr.totalKw / 1e3).toFixed(0)} kN/m, bounce ${sr.bounceHz.toFixed(0)} Hz, ${sr.nodes.length} pad nodes, preload ${(sr.preloadTop * 1e3).toFixed(2)} / ${(sr.preloadBottom * 1e3).toFixed(2)} mm`);

420 } else lines.push("Free plate (no stand)");

421 lines.push(`Decay T60: ${t60At(pl.loss, 100).toFixed(2)} s at 100 Hz, ${t60At(pl.loss, 1000).toFixed(2)} s at 1 kHz, ${t60At(pl.loss, 5000).toFixed(2)} s at 5 kHz`);

422 void p;

423 $("designInfo").innerHTML = lines.join("\n");

424 }

425

426 private updateNotes(): void {

427 const pl = this.plate;

428 if (!pl) return;

429 const p = this.form.get();

430 const g = pl.grid;

431 const hm = meanThickness(pl);

432 const f3 = dispersionFrequency(pl.mat, hm, g.hx, 0.03), f10 = dispersionFrequency(pl.mat, hm, g.hx, 0.1);

433 const wmax = maxAngularFrequency(g, pl.mat, thicknessRange(pl).max);

434 const dtMax = (CFL * 2) / wmax;

435 const sps = Math.ceil(1 / (p.fs * dtMax));

436 const dt = 1 / (p.fs * sps);

437 const fit = fitSigma(pl.loss, pl.mat, hm);

438 const t60f = (f: number) => (LN1000 / fittedRate(fit, f)).toFixed(2);

439 const lines = [

440 `Grid ${g.nx} x ${g.ny}, ${countInside(g)} plate nodes. Grid dispersion lowers the bending partials by 3% near ${(f3 / 1e3).toFixed(1)} kHz and by 10% near ${(f10 / 1e3).toFixed(1)} kHz (at the mean thickness).`,

441 `Linear model: modes up to ${(p.modeMaxFreq / 1e3).toFixed(1)} kHz${this.modes ? `, ${this.modes.count} found in ${this.modes.seconds.toFixed(1)} s` : ""}${this.modes && this.modes.missing ? ` <span class="warn">(${this.modes.missing} missing)</span>` : ""}.`,

442 `Full model: time step ${(dt * 1e6).toFixed(2)} us (${sps} per sample, in-plane wave speed ${inPlaneSpeed(pl.mat).toFixed(0)} m/s), ${((p.duration * p.fs * sps) / 1e6).toFixed(1)} million steps for ${p.duration} s. Losses fitted as sigma0 = ${fit.sigma0.toFixed(2)} 1/s, sigma1 = ${fit.sigma1.toExponential(2)} m^2/s: T60 ${t60f(100)} / ${t60f(1000)} / ${t60f(5000)} s at 100 Hz / 1 kHz / 5 kHz (requested ${t60At(pl.loss, 100).toFixed(2)} / ${t60At(pl.loss, 1000).toFixed(2)} / ${t60At(pl.loss, 5000).toFixed(2)}).`,

443 ];

444 this.form.setNotes("Grid and numerics", lines.join("\n"));

445 const patch = strikePatch(pl, p);

446 const sp = strikePoint(pl, p);

447 const sl = [`Strike at (${(sp.x * 1e3).toFixed(0)}, ${(sp.y * 1e3).toFixed(0)}) mm on ${patch.nodes.length} node${patch.nodes.length === 1 ? "" : "s"} (${(patch.mass * 1e3).toFixed(2)} g).`];

448 if (this.lastContact) sl.push(`Last linear strike: peak force ${this.lastContact.peakForce.toFixed(0)} N, contact ${(this.lastContact.contactTime * 1e3).toFixed(2)} ms.`);

449 if (this.sim) { const st = this.sim.status().stick; sl.push(`Full simulation: peak force ${st.maxForce.toFixed(0)} N${st.withdrawn ? ", stick withdrawn" : ""}.`); }

450 this.form.setNotes("Strike", sl.join("\n"));

451 }

452

453 private updateMarkers(): void {

454 const pl = this.plate;

455 if (!pl) return;

456 const p = this.form.get();

457 const sp = strikePoint(pl, p);

458 const L = listenerPosition(p);

459 this.renderer.setMarkers({

460 strike: { x: sp.x, y: sp.y, radius: p.contactRadius },

461 stand: pl.stand ? { x: pl.stand.x, y: pl.stand.y, innerRadius: pl.stand.pad.innerRadius, outerRadius: pl.stand.pad.outerRadius } : null,

462 listener: L,

463 });

464 }

465

466 // ---------- Linear model ----------

467

468 private computeModes(): void {

469 const pl = this.plate, gen = this.designGeneration;

470 if (!pl) return;

471 const p = this.form.get();

472 const fMax = Math.min(p.modeMaxFreq, p.fs / 2);

473 this.modeBrowser.clear("");

474 this.modeBrowser.setProgress(0, "Computing the modes...");

475 this.updateButtons();

476 this.modesBusy = this.modesBusy.then(async () => {

477 if (gen !== this.designGeneration) return;

478 const t0 = performance.now();

479 let sys: LinearSystem;

480 try {

481 sys = assemble(pl);

482 } catch (e) {

483 this.modeBrowser.setProgress(null, `Assembly failed: ${e instanceof Error ? e.message : String(e)}`);

484 return;

485 }

486 let modes: ModeSet;

487 try {

488 if (this.pool) modes = await this.pool.modes(sys, fMax, (d, t) => { if (gen === this.designGeneration) this.modeBrowser.setProgress(t ? d / t : 0, `Computing the modes: slice ${d} of ${t}`); });

489 else {

490 const { computeModes, localRunner } = await import("./modal/modes.ts");

491 modes = await computeModes(sys, fMax, localRunner(sys));

492 }

493 } catch (e) {

494 this.modeBrowser.setProgress(null, `Mode computation failed: ${e instanceof Error ? e.message : String(e)}`);

495 return;

496 }

497 if (gen !== this.designGeneration) return;

498 this.sys = sys;

499 this.modes = modes;

500 this.model = modalModel(pl, sys, modes);

501 if (this.pool) await this.pool.setModel(this.model);

502 const secs = (performance.now() - t0) / 1000;

503 const rows = Array.from(modes.freqs).map((f, m) => ({ freq: f, t60: LN1000 / Math.min(decayRate(pl.loss, f) + this.model!.padSigma[m], 0.99 * 2 * Math.PI * f) }));

504 const kind = sys.fields === 1 ? "bending modes" : "modes (bending coupled to stretching)";

505 const info = `${modes.count} ${kind} up to ${(fMax / 1e3).toFixed(1)} kHz in ${secs.toFixed(1)} s (${sys.n} unknowns${modes.missing ? `, ${modes.missing} missing` : ""}). Click a mode to see its shape.`;

506 this.modeBrowser.setProgress(null);

507 this.modeBrowser.setModes(rows, info);

508 this.updateNotes();

509 this.updateTicks();

510 this.updateButtons();

511 });

512 }

513

514 private showMode(m: number | null): void {

515 if (m === null) { this.setView(this.rec ? "movie" : "design"); return; }

516 if (!this.model) return;

517 this.view = "mode";

518 const shape = modeShapeOnGrid(this.model, m);

519 // Scale the mass-normalized shape to a visible amplitude: 1 mm peak.

520 let peak = 0;

521 for (const v of shape) peak = Math.max(peak, Math.abs(v));

522 const w = new Float32Array(shape.length);

523 for (let k = 0; k < w.length; k++) w[k] = (shape[k] / (peak || 1)) * 1e-3;

524 this.renderer.setField(w);

525 this.overlay.textContent = `Mode ${m + 1}: ${this.model.freqs[m].toFixed(1)} Hz (shape scaled to 1 mm)`;

526 }

527

528 private scheduleSynth(): void {

529 if (this.synthTimer !== null) clearTimeout(this.synthTimer);

530 this.synthTimer = window.setTimeout(() => { this.synthTimer = null; void this.runLinear(); }, 250);

531 }

532

533 /** Synthesizes the strike with the current parameters (linear model). */

534 async runLinear(): Promise<void> {

535 const pl = this.plate, model = this.model;

536 if (!pl || !model) return;

537 if (this.synthBusy) { this.synthPending = true; return; }

538 this.synthBusy = true;

539 const p = this.form.get();

540 const gen = this.designGeneration;

541 const t0 = performance.now();

542 this.runStatus.textContent = "Synthesizing...";

543 try {

544 let audio: Float32Array, frames: Float32Array, nFrames: number, contact: ContactResult;

545 if (this.pool) {

546 const r = await this.pool.synthesize(model, pl, pl.loss, p, (a, c) => {

547 if (gen !== this.designGeneration) return;

548 this.installRecording(a, [], p, "linear");

549 this.lastContact = c;

550 this.runStatus.textContent = `Audio ready in ${((performance.now() - t0) / 1000).toFixed(2)} s; movie frames...`;

551 });

552 audio = r.audio; frames = r.frames; nFrames = r.nFrames; contact = r.contact;

553 } else {

554 const { synthesize } = await import("./modal/synth.ts");

555 const r = synthesize(model, pl, pl.loss, p, true);

556 audio = r.audio; frames = r.frames; nFrames = r.nFrames; contact = r.contact;

557 }

558 if (gen !== this.designGeneration) return;

559 const n = pl.grid.n;

560 const frameList: Float32Array[] = [];

561 for (let f = 0; f < nFrames; f++) frameList.push(frames.subarray(f * n, (f + 1) * n));

562 this.installRecording(audio, frameList, p, "linear");

563 this.lastContact = contact;

564 this.synthesized = true;

565 const secs = (performance.now() - t0) / 1000;

566 this.runStatus.textContent = `Linear model: ${model.count} modes, ${p.duration} s synthesized in ${secs.toFixed(2)} s. Peak ${peakSpl(audio).toFixed(0)} dB SPL, contact ${(contact.contactTime * 1e3).toFixed(2)} ms, peak force ${contact.peakForce.toFixed(0)} N.`;

567 this.updateNotes();

568 } catch (e) {

569 this.runStatus.textContent = `Synthesis failed: ${e instanceof Error ? e.message : String(e)}`;

570 } finally {

571 this.synthBusy = false;

572 if (this.synthPending) { this.synthPending = false; void this.runLinear(); }

573 }

574 }

575

576 // ---------- Full simulation ----------

577

578 async runFull(): Promise<void> {

579 const pl = this.plate;

580 if (!pl || !this.device || this.running) return;

581 const p = this.form.get();

582 this.sim?.destroy();

583 const hm = meanThickness(pl);

584 const fit = fitSigma(pl.loss, pl.mat, hm);

585 const loss: FullLoss = fullLoss(fit, standRates(pl), decayRate(pl.loss, 5000));

586 this.sim = new Simulation(this.device, pl, p, loss);

587 this.rec = { audio: new Float32Array(0), samples: 0, fs: p.fs, frames: [new Float32Array(pl.grid.n)], fps: p.fps, source: "full" };

588 this.spec.reset();

589 this.spec.setOptions({ fs: p.fs });

590 this.spec.setDuration(p.duration);

591 this.running = true;

592 this.paused = false;

593 this.setLocked(true);

594 this.setView("live");

595 this.updateButtons();

596 await this.fullLoop();

597 }

598

599 private async fullLoop(): Promise<void> {

600 const sim = this.sim;

601 if (!sim) return;

602 const t0 = performance.now();

603 let lastUi = 0;

604 while (this.running && sim.phase === "recording") {

605 if (this.paused) { await new Promise((r) => setTimeout(r, 50)); continue; }

606 await sim.runBatch();

607 if (!this.rec || this.sim !== sim) break;

608 // New audio and frames.

609 const rec = this.rec;

610 const newSamples = sim.samples - rec.samples;

611 if (newSamples > 0) {

612 const chunk = sim.audio.subarray(rec.samples, sim.samples);

613 this.spec.append(chunk);

614 rec.audio = sim.audio; rec.samples = sim.samples;

615 }

616 rec.frames = sim.frames;

617 if (this.view === "live") this.renderer.setField(sim.frames[sim.frames.length - 1]);

618 const now = performance.now();

619 if (now - lastUi > 100) {

620 lastUi = now;

621 const st = sim.status();

622 const elapsed = (now - t0) / 1000;

623 this.runStatus.textContent = `Full model: t = ${st.t.toFixed(3)} s, ${(st.totalSteps / elapsed / 1000).toFixed(0)}k steps/s (${(elapsed / Math.max(st.t, 1e-3)).toFixed(0)} s per second of sound), peak ${peakSpl(sim.recordedAudio()).toFixed(0)} dB SPL, stick force ${st.stick.force.toFixed(0)} N${st.delayClamped ? ", delay spread clamped" : ""}`;

624 this.scrub.max = String(Math.max(0, rec.frames.length - 1));

625 this.updatePeak();

626 }

627 }

628 if (this.sim === sim) {

629 this.running = false;

630 this.setLocked(false);

631 const st = sim.status();

632 this.runStatus.textContent = `Full model: ${st.t.toFixed(2)} s recorded, peak ${peakSpl(sim.recordedAudio()).toFixed(0)} dB SPL, peak force ${st.stick.maxForce.toFixed(0)} N, largest displacement ${(st.wmax * 1e3).toFixed(2)} mm.`;

633 if (this.rec) { this.rec.audio = sim.recordedAudio(); this.rec.samples = sim.samples; this.rec.frames = sim.frames; }

634 this.updateNotes();

635 this.updateButtons();

636 this.updatePeak();

637 }

638 }

639

640 // ---------- Run control ----------

641

642 private setRunMode(mode: RunMode): void {

643 if (mode === "full" && !this.device) mode = "linear";

644 this.runMode = mode;

645 this.runModeSel.value = mode;

646 if (mode === "linear" && this.plate && !this.modes) this.computeModes();

647 if (mode === "full") this.modeBrowser.clear("Switch to the linear model to compute the modes.");

648 this.updateButtons();

649 }

650

651 private start(): void {

652 if (this.runMode === "linear") void this.runLinear();

653 else void this.runFull();

654 }

655 private pause(): void {

656 if (!this.running) return;

657 this.paused = !this.paused;

658 this.pauseBtn.textContent = this.paused ? "Resume" : "Pause";

659 }

660 private stopRun(): void {

661 if (this.sim && this.running) { this.sim.stop(); this.running = false; }

662 this.paused = false;

663 this.pauseBtn.textContent = "Pause";

664 this.setLocked(false);

665 this.updateButtons();

666 }

667 private continueRun(): void {

668 const sim = this.sim;

669 if (!sim || this.running || !sim.canContinue()) return;

670 sim.setDuration(this.form.get().duration);

671 this.running = true;

672 this.setLocked(true);

673 this.setView("live");

674 this.updateButtons();

675 void this.fullLoop();

676 }

677

678 private setLocked(locked: boolean): void {

679 this.editor.setLocked(locked);

680 this.form.setLocked(locked);

681 this.runModeSel.disabled = locked;

682 }

683

684 private updateButtons(): void {

685 const linear = this.runMode === "linear";

686 const canLinear = linear && !!this.model && !this.synthBusy;

687 const canFull = !linear && !!this.plate && !!this.device && !this.running;

688 this.startBtn.disabled = !(canLinear || canFull);

689 this.startBtn.textContent = linear ? "Synthesize" : "Start";

690 this.pauseBtn.disabled = linear || !this.running;

691 this.stopBtn.disabled = linear || !this.running;

692 this.continueBtn.disabled = linear || this.running || !this.sim || !this.sim.canContinue() || this.sim.samples >= Math.round(this.form.get().duration * this.form.get().fs);

693 this.pauseBtn.hidden = linear; this.stopBtn.hidden = linear; this.continueBtn.hidden = linear;

694 this.liveBtn.hidden = linear;

695 }

696

697 // ---------- Recording, view, playback ----------

698

699 private installRecording(audio: Float32Array, frames: Float32Array[], p: SimParams, source: RunMode): void {

700 this.rec = { audio, samples: audio.length, fs: p.fs, frames, fps: p.fps, source };

701 this.spec.setOptions({ fs: p.fs });

702 this.spec.setDuration(p.duration);

703 this.spec.setSignal(audio);

704 this.scrub.max = String(Math.max(0, frames.length - 1));

705 if (frames.length > 0) {

706 this.frameIndex = Math.min(this.frameIndex, frames.length - 1);

707 if (this.view !== "mode") { this.setView("movie"); this.showFrame(); }

708 }

709 this.updatePeak();

710 this.updateButtons();

711 }

712

713 private setView(v: ViewState): void {

714 this.view = v;

715 if (v === "design") { this.renderer.setField(null); this.overlay.textContent = this.plate ? "Stress-free shape" : ""; }

716 else if (v === "live") { this.overlay.textContent = "Live"; if (this.sim) this.renderer.setField(this.sim.frames[this.sim.frames.length - 1]); }

717 else if (v === "movie") this.showFrame();

718 }

719

720 private showFrame(): void {

721 const rec = this.rec;

722 if (!rec || rec.frames.length === 0) return;

723 const f = Math.max(0, Math.min(rec.frames.length - 1, this.frameIndex));

724 this.frameIndex = f;

725 this.scrub.value = String(f);

726 this.timeLabel.textContent = `${(f / rec.fps).toFixed(3)} s`;

727 this.renderer.setField(rec.frames[f]);

728 this.overlay.textContent = `${rec.source === "linear" ? "Linear" : "Full"} model, t = ${(f / rec.fps).toFixed(3)} s`;

729 }

730

731 private playable(): Float32Array | null {

732 const rec = this.rec;

733 if (!rec || rec.samples === 0) return null;

734 const sig = rec.audio.subarray(0, rec.samples);

735 return applyLevel(sig, levelGain(sig, rec.fs, this.levelMode, this.gainDb));

736 }

737

738 private updatePeak(): void {

739 const s = this.playable();

740 if (!s) { this.peakLabel.textContent = ""; this.downloadBtn.disabled = true; this.playBtn.disabled = true; return; }

741 const db = peakDbfs(s);

742 this.peakLabel.textContent = `Peak ${db.toFixed(1)} dBFS${db > -0.5 ? " (clipping)" : ""}`;

743 this.peakLabel.className = db > -0.5 ? "badge warn" : "badge";

744 this.downloadBtn.disabled = false;

745 this.playBtn.disabled = false;

746 }

747

748 private togglePlay(): void {

749 if (this.player.playing) { this.player.stop(); this.playBtn.textContent = "Play"; this.spec.setCursor(null); return; }

750 const s = this.playable(), rec = this.rec;

751 if (!s || !rec) return;

752 const start = rec.frames.length > 1 ? this.frameIndex / rec.fps : 0;

753 this.playBtn.textContent = "Stop";

754 const prevView = this.view;

755 this.player.play(s, rec.fs, start, () => { this.playBtn.textContent = "Play"; this.spec.setCursor(null); if (prevView === "live") this.setView("live"); });

756 const tick = () => {

757 if (!this.player.playing) return;

758 const t = this.player.position();

759 this.spec.setCursor(t);

760 if (rec.frames.length > 1) { this.frameIndex = Math.round(t * rec.fps); this.view = "movie"; this.showFrame(); }

761 requestAnimationFrame(tick);

762 };

763 requestAnimationFrame(tick);

764 }

765

766 private download(): void {

767 const s = this.playable(), rec = this.rec;

768 if (!s || !rec) return;

769 const blob = encodeWav(s, rec.fs);

770 const a = document.createElement("a");

771 a.href = URL.createObjectURL(blob);

772 a.download = `${(this.plate?.name ?? "cymbalsim").replace(/[^a-z0-9]+/gi, "-").toLowerCase()}-${rec.source}.wav`;

773 a.click();

774 setTimeout(() => URL.revokeObjectURL(a.href), 1000);

775 }

776

777 private updateTicks(): void {

778 this.spec.setTicks(this.showTicks && this.modes ? Array.from(this.modes.freqs) : null);

779 }

780

781 // ---------- Tests ----------

782

783 async selfTest(): Promise<string> {

784 if (!this.device) return "no WebGPU";

785 const lines: string[] = [];

786 for (const id of ["flat-rectangle", "bowed-rectangle", "crash-16", "crash-bell-16", "ellipse"]) {

787 const pr = presetById(id)!;

788 const d = compileDesign(pr.source);

789 const pl = evaluatePlate(d, 0.012);

790 const r = await runSelfTest(this.device, pl, this.form.get());

791 lines.push(`${id}: max relative error ${r.maxRel.toExponential(2)} (${r.n} nodes)`);

792 }

793 return lines.join("\n");

794 }

795

796 private testStatus(): unknown {

797 return {

798 design: this.design?.name ?? null,

799 modes: this.modes ? { count: this.modes.count, missing: this.modes.missing, first: Array.from(this.modes.freqs.slice(0, 5)) } : null,

800 synthesized: this.synthesized,

801 running: this.running,

802 samples: this.rec?.samples ?? 0,

803 frames: this.rec?.frames.length ?? 0,

804 source: this.rec?.source ?? null,

805 peakPressure: this.rec ? Array.from(this.rec.audio.subarray(0, this.rec.samples)).reduce((m, v) => Math.max(m, Math.abs(v)), 0) : 0,

806 sim: this.sim ? this.sim.status() : null,

807 contact: this.lastContact ? { peakForce: this.lastContact.peakForce, contactTime: this.lastContact.contactTime } : null,

808 editorStatus: ($("design").querySelector(".editor-status") as HTMLElement | null)?.textContent ?? "",

809 };

810 }

811}

812

813const app = new App();

814app.init().catch((e) => {

815 console.error(e);

816 $("viewOverlay").textContent = `Failed to start: ${e instanceof Error ? e.message : String(e)}`;

817});

818

819export { app, PRESETS, isFlat, formatNumber };