src/main.ts at 7710254e1ac42e0e395f3f6800e1b7e76a2e1c82

1// Application: design editor, parameter form, run loop, live and movie

2// views, spectrogram, playback, WAV download, and the test hooks on

3// window.steelsim.

5import { type Plate, type SimParams, countInside, defaultParams, massProperties, mountPatch, nodeWeights, strikePoint, thicknessRange } from "./params.ts";

6import { DesignError, evaluatePlate, profileStats } from "./design.ts";

7import { PRESETS } from "./presets.ts";

8import { Simulation, type SimStatus } from "./sim/simulation.ts";

9import { Renderer, type ColorMode, type ViewMode } from "./render/renderer.ts";

10import { Spectrogram } from "./audio/spectrogram.ts";

11import { Player } from "./audio/player.ts";

12import { encodeWav } from "./audio/wav.ts";

13import { levelGain, peakDbfs, type LevelMode } from "./audio/level.ts";

14import { ParamForm } from "./ui/form.ts";

15import { DesignEditor } from "./ui/editor.ts";

16import { runSelfTest, selfTestPassed, type SelfTestCase } from "./selftest.ts";

18const $ = <T extends HTMLElement>(id: string) => document.getElementById(id) as T;

20/** Slope above which the shallow-shell treatment of the profile is doubtful. */

21const SLOPE_LIMIT = 0.1;

23// ---------- State ----------

25const params: SimParams = { ...defaultParams };

26let form: ParamForm;

27let editor: DesignEditor;

28let device: GPUDevice | null = null;

29let sim: Simulation | null = null;

30let renderer: Renderer | null = null;

31let running = false;

32let paused = false;

33let live = true;

34let scrubFrame = 0;

35let movieBuf: GPUBuffer | null = null;

36let movieBufFrame = -1;

37/** The design evaluated at the current spacing, or null while the script has an error. */

38let plate: Plate | null = null;

39let plateError: string | null = null;

40/** Show the design (its stress-free shape) instead of the simulation. */

41let previewMode = true;

42let preview: { plate: Plate; w0: GPUBuffer; zero: GPUBuffer; nw: GPUBuffer; hn: GPUBuffer; wmax: number; stale: boolean } | null = null;

43const spec = new Spectrogram({ windowSize: 2048, hop: 512, fmax: 5000, dbFloor: 80, logFrequency: false });

44const player = new Player();

45let lastStatsTime = 0, lastStatsSteps = 0, stepsPerSec = 0;

46let duration = params.duration;

48// ---------- Controls ----------

50const btnStart = mkButton("Start", "primary");

51const btnPause = mkButton("Pause");

52const btnStop = mkButton("Stop");

53const btnContinue = mkButton("Continue");

54const durInput = document.createElement("input");

56function mkButton(text: string, cls = ""): HTMLButtonElement {

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

58 b.textContent = text;

59 b.className = cls;

60 return b;

61}

63function buildControls(): void {

64 const c = $("controls");

65 const durRow = document.createElement("div");

66 durRow.className = "field";

67 const l = document.createElement("label");

68 l.textContent = "Recorded duration";

69 durInput.type = "number";

70 durInput.step = "0.5";

71 durInput.min = "0.1";

72 durInput.value = String(duration);

73 durInput.addEventListener("change", () => {

74 const v = parseFloat(durInput.value);

75 if (isFinite(v) && v > 0) {

76 duration = v;

77 params.duration = v;

78 sim?.setDuration(v);

79 form.updateNotes();

80 updateButtons();

81 }

82 });

83 const u = document.createElement("span");

84 u.className = "unit";

85 u.textContent = "s";

86 durRow.append(l, durInput, u);

87 c.append(durRow, btnStart, btnPause, btnStop, btnContinue);

88 btnStart.addEventListener("click", () => void start());

89 btnPause.addEventListener("click", () => {

90 paused = !paused;

91 btnPause.textContent = paused ? "Resume" : "Pause";

92 if (!paused) void runLoop();

93 });

94 btnStop.addEventListener("click", () => {

95 if (!sim) return;

96 sim.stop();

97 paused = false;

98 btnPause.textContent = "Pause";

99 if (!running) {

100 setEditable(true);

101 updateButtons();

102 }

103 });

104 btnContinue.addEventListener("click", () => {

105 if (!sim) return;

106 sim.setDuration(duration);

107 if (sim.phase !== "done") void runLoop();

108 updateButtons();

109 });

110 updateButtons();

111}

112

113function updateButtons(): void {

114 const s = sim?.status();

115 btnStart.disabled = !device || !plate;

116 btnPause.disabled = !sim || s?.phase === "done" || (!running && !paused);

117 btnStop.disabled = !sim || s?.phase === "done";

118 btnContinue.disabled = !sim || running || !sim.canContinue();

119}

120

121function setEditable(enabled: boolean): void {

122 form.setEnabled(enabled);

123 editor.setEnabled(enabled);

124}

125

126// ---------- Splitter ----------

127

128const SIDEBAR_KEY = "steelsim41.sidebarWidth";

129const SIDEBAR_DEFAULT = 420;

130const SIDEBAR_MIN = 280;

131/** Leaves at least this much for the view, so the panel cannot swallow the page. */

132const MAIN_MIN = 320;

133

134function sidebarWidth(w: number): number {

135 return Math.round(Math.max(SIDEBAR_MIN, Math.min(w, Math.max(SIDEBAR_MIN, window.innerWidth - MAIN_MIN))));

136}

137

138/** Drag handle between the panel and the view; the width is remembered across visits. */

139function buildSplitter(): void {

140 const bar = $("splitter");

141 const sidebar = $("sidebar");

142 const setWidth = (w: number, remember: boolean) => {

143 const px = sidebarWidth(w);

144 sidebar.style.width = `${px}px`;

145 if (remember) try { localStorage.setItem(SIDEBAR_KEY, String(px)); } catch { /* storage may be unavailable */ }

146 };

147 let stored = NaN;

148 try { stored = parseFloat(localStorage.getItem(SIDEBAR_KEY) ?? ""); } catch { /* ignore */ }

149 setWidth(isFinite(stored) ? stored : SIDEBAR_DEFAULT, false);

150 let dragging = false;

151 bar.addEventListener("pointerdown", (e) => {

152 dragging = true;

153 bar.setPointerCapture(e.pointerId);

154 bar.classList.add("dragging");

155 document.body.classList.add("resizing");

156 e.preventDefault();

157 });

158 bar.addEventListener("pointermove", (e) => {

159 if (!dragging) return;

160 setWidth(e.clientX - sidebar.getBoundingClientRect().left, false);

161 });

162 const end = (e: PointerEvent) => {

163 if (!dragging) return;

164 dragging = false;

165 bar.releasePointerCapture(e.pointerId);

166 bar.classList.remove("dragging");

167 document.body.classList.remove("resizing");

168 setWidth(sidebar.getBoundingClientRect().width, true);

169 };

170 bar.addEventListener("pointerup", end);

171 bar.addEventListener("pointercancel", end);

172 bar.addEventListener("dblclick", () => setWidth(SIDEBAR_DEFAULT, true));

173 // A narrower window may leave the stored width too wide for the view.

174 window.addEventListener("resize", () => setWidth(sidebar.getBoundingClientRect().width, false));

175}

176

177// ---------- View toolbars ----------

178

179const viewMode = { value: "3d" as ViewMode };

180const colorSel = document.createElement("select");

181const scrub = document.createElement("input");

182const timeLabel = document.createElement("span");

183const btnLive = mkButton("Live");

184const btnDesign = mkButton("Design");

185const btnPlay = mkButton("Play");

186const btnWav = mkButton("Download .wav");

187const levelSel = document.createElement("select");

188const gainSlider = document.createElement("input");

189const gainLabel = document.createElement("span");

190const peakLabel = document.createElement("span");

191let exagInput: HTMLInputElement;

192let rangeInput: HTMLInputElement;

193let shapeCheck: HTMLInputElement;

194

195function gainDb(): number {

196 return parseFloat(gainSlider.value) || 0;

197}

198function levelMode(): LevelMode {

199 return levelSel.value as LevelMode;

200}

201

202function updateLevelReadout(): void {

203 gainLabel.textContent = `${gainDb() >= 0 ? "+" : ""}${gainDb()} dB`;

204 gainSlider.disabled = levelMode() !== "absolute";

205 if (!sim || sim.samples === 0) { peakLabel.textContent = ""; return; }

206 const audio = sim.recordedAudio();

207 const db = peakDbfs(audio, levelGain(audio, sim.fs, levelMode(), gainDb()));

208 peakLabel.textContent = isFinite(db) ? `peak ${db.toFixed(1)} dBFS${db > 0 ? " (clipped)" : ""}` : "";

209 peakLabel.className = db > 0 ? "warn" : "sub";

210 peakLabel.style.margin = "0";

211}

212

213function buildViewToolbar(): void {

214 const tb = $("viewToolbar");

215 const seg = document.createElement("span");

216 seg.className = "seg";

217 const b2 = mkButton("2D"), b3 = mkButton("3D", "on");

218 b2.addEventListener("click", () => { viewMode.value = "2d"; b2.classList.add("on"); b3.classList.remove("on"); });

219 b3.addEventListener("click", () => { viewMode.value = "3d"; b3.classList.add("on"); b2.classList.remove("on"); });

220 seg.append(b2, b3);

221 for (const [v, t] of [["field", "Height / displacement"], ["thickness", "Thickness"]]) {

222 const o = document.createElement("option");

223 o.value = v; o.textContent = t;

224 colorSel.appendChild(o);

225 }

226 exagInput = numInput(1, 0.5);

227 rangeInput = numInput(0, 0.5);

228 shapeCheck = document.createElement("input");

229 shapeCheck.type = "checkbox";

230 shapeCheck.checked = true;

231 shapeCheck.title = "Show the total shape (design profile plus vibration); unticked, only the vibration";

232 const hint = document.createElement("span");

233 hint.className = "sub";

234 hint.style.margin = "0";

235 hint.textContent = "3D: drag to orbit, wheel to zoom";

236 tb.append(seg, labeled("Color", colorSel), labeled("Exaggeration ×", exagInput), labeled("Color range (mm, 0 = auto)", rangeInput), labeled("Show profile", shapeCheck), hint);

237}

238

239function buildMovieToolbar(): void {

240 const tb = $("movieToolbar");

241 scrub.type = "range";

242 scrub.min = "0"; scrub.max = "0"; scrub.value = "0";

243 timeLabel.className = "time";

244 // Playback drives the movie; afterwards the view returns to where it was (live or scrubbed).

245 let liveBeforePlay = true;

246 const endPlayback = () => {

247 btnPlay.textContent = "Play";

248 if (liveBeforePlay) {

249 live = true;

250 updateLiveButton();

251 }

252 };

253 scrub.addEventListener("input", () => {

254 live = false;

255 liveBeforePlay = false;

256 previewMode = false;

257 scrubFrame = parseInt(scrub.value);

258 if (player.playing) player.stop();

259 updateLiveButton();

260 });

261 btnLive.addEventListener("click", () => { live = true; liveBeforePlay = true; previewMode = false; updateLiveButton(); });

262 btnDesign.title = "Show the design's stress-free shape instead of the simulation";

263 btnDesign.addEventListener("click", () => { showPreview(); updateLiveButton(); });

264 btnPlay.addEventListener("click", () => {

265 if (player.playing) { player.stop(); endPlayback(); return; }

266 if (!sim || sim.samples === 0) return;

267 liveBeforePlay = live;

268 const offset = live ? 0 : scrubFrame / sim.fps;

269 live = false;

270 previewMode = false;

271 player.play(sim.recordedAudio(), sim.fs, offset, levelMode(), gainDb());

272 btnPlay.textContent = "Stop";

273 updateLiveButton();

274 });

275 player.onEnded = endPlayback;

276 btnWav.addEventListener("click", () => {

277 if (!sim || sim.samples === 0) return;

278 const blob = encodeWav(sim.recordedAudio(), sim.fs, levelMode(), gainDb());

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

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

281 const name = sim.plate.name.replace(/[^a-z0-9]+/gi, "_").replace(/^_+|_+$/g, "").toLowerCase() || "cymbal";

282 a.download = `${name}_${(sim.samples / sim.fs).toFixed(1)}s_${sim.fs}Hz.wav`;

283 a.click();

284 setTimeout(() => URL.revokeObjectURL(a.href), 5000);

285 });

286 for (const [v, t] of [["absolute", "Absolute (0 dBFS = 1 Pa at 0 dB)"], ["loudness", "Loudness (RMS, soft clip)"], ["peak", "Peak"]]) {

287 const o = document.createElement("option");

288 o.value = v; o.textContent = t;

289 levelSel.appendChild(o);

290 }

291 gainSlider.type = "range";

292 gainSlider.min = "-40"; gainSlider.max = "60"; gainSlider.step = "1"; gainSlider.value = "20";

293 gainSlider.style.width = "120px";

294 gainSlider.style.flex = "none";

295 const restart = () => {

296 updateLevelReadout();

297 const pos = player.position();

298 if (pos !== null && sim) player.play(sim.recordedAudio(), sim.fs, pos, levelMode(), gainDb());

299 };

300 gainSlider.addEventListener("input", restart);

301 levelSel.addEventListener("change", restart);

302 tb.append(btnPlay, btnLive, btnDesign, scrub, timeLabel, labeled("Level", levelSel), labeled("Gain", gainSlider), gainLabel, peakLabel, btnWav);

303 updateLevelReadout();

304 updateLiveButton();

305}

306

307function updateLiveButton(): void {

308 btnLive.classList.toggle("on", live && !previewMode);

309 btnLive.disabled = !sim || (live && !previewMode);

310 btnDesign.classList.toggle("on", previewMode);

311 btnDesign.disabled = previewMode;

312}

313

314function buildSpecToolbar(): void {

315 const tb = $("specToolbar");

316 const win = document.createElement("select");

317 for (const n of [512, 1024, 2048, 4096, 8192]) {

318 const o = document.createElement("option");

319 o.value = String(n); o.textContent = String(n);

320 win.appendChild(o);

321 }

322 win.value = "2048";

323 const hop = numInput(512, 64);

324 const fmax = numInput(5000, 500);

325 const floor = numInput(80, 5);

326 const logf = document.createElement("input");

327 logf.type = "checkbox";

328 const apply = () => {

329 if (!sim) return;

330 spec.configure(

331 { windowSize: parseInt(win.value), hop: Math.max(16, parseInt(hop.value)), fmax: Math.min(sim.fs / 2, parseFloat(fmax.value)), dbFloor: parseFloat(floor.value), logFrequency: logf.checked },

332 sim.recordedAudio(), sim.samples,

333 );

334 };

335 for (const el of [win, hop, fmax, floor, logf]) el.addEventListener("change", apply);

336 tb.append(document.createTextNode("Spectrogram"), labeled("Window", win), labeled("Hop", hop), labeled("Max Hz", fmax), labeled("dB range", floor), labeled("Log freq.", logf));

337}

338

339function numInput(v: number, step: number): HTMLInputElement {

340 const i = document.createElement("input");

341 i.type = "number"; i.value = String(v); i.step = String(step);

342 return i;

343}

344function labeled(text: string, el: HTMLElement): HTMLLabelElement {

345 const l = document.createElement("label");

346 l.append(text, el);

347 return l;

348}

349

350// ---------- Design ----------

351

352/** Re-evaluates the current design at the current spacing and refreshes everything that depends on it. */

353function rebuildPlate(): void {

354 const design = editor.design;

355 plate = null;

356 plateError = editor.error;

357 if (design) {

358 try {

359 plate = evaluatePlate(design, params.spacing);

360 } catch (e) {

361 plateError = e instanceof DesignError ? e.message : String(e);

362 }

363 }

364 form.setPlate(plate);

365 editor.setStatus(plateError, plate ? designSummary(plate) : "");

366 showPreview();

367 updateButtons();

368}

369

370function fmtMm(v: number): string {

371 return `${(v * 1e3).toFixed(2)} mm`;

372}

373

374function designSummary(pl: Plate): string {

375 const g = pl.grid;

376 const hr = thicknessRange(pl);

377 const { mass } = massProperties(pl);

378 const { peakToPeak, maxSlope } = profileStats(pl);

379 const rows: [string, string][] = [

380 ["Design", pl.name],

381 ["Bounding box", `${fmtMm(pl.Lx)} × ${fmtMm(pl.Ly)} (${(pl.Lx / 0.0254).toFixed(1)} × ${(pl.Ly / 0.0254).toFixed(1)} in)`],

382 ["Material", `E ${(pl.mat.E / 1e9).toFixed(0)} GPa, ν ${pl.mat.nu}, ρ ${pl.mat.rho} kg/m³`],

383 ["Thickness", hr.min === hr.max ? fmtMm(hr.min) : `${fmtMm(hr.min)} to ${fmtMm(hr.max)} (mean ${fmtMm(hr.mean)})`],

384 ["Mass", `${(mass * 1e3).toFixed(0)} g`],

385 ["Grid", `${g.nx} × ${g.ny}, ${countInside(g)} nodes in the plate`],

386 ["Profile", peakToPeak > 0 ? `${fmtMm(peakToPeak)} peak to peak, largest slope ${maxSlope.toFixed(3)}` : "flat"],

387 ];

388 if (pl.mount) {

389 const mp = mountPatch(pl);

390 rows.push(["Mount", `${mp?.nodes.length ?? 0} nodes within ${fmtMm(pl.mount.radius)} of (${fmtMm(pl.mount.x)}, ${fmtMm(pl.mount.y)}); ${pl.mount.stiffness.toExponential(1)} N/m, ${pl.mount.damping} N s/m`]);

391 } else {

392 rows.push(["Mount", "none (free plate, inertia relief)"]);

393 }

394 rows.push(["Losses", `σ₀ ${pl.loss.sigma0} 1/s, σ₁ ${pl.loss.sigma1} m²/s, in-plane ${pl.loss.sigmaIn} 1/s`]);

395 let html = rows.map(([a, b]) => `<div class="row"><span>${a}</span><span>${b}</span></div>`).join("");

396 if (maxSlope > SLOPE_LIMIT) html += `<div class="warn">The largest slope of the profile, ${maxSlope.toFixed(2)}, is beyond the shallow-shell range of about ${SLOPE_LIMIT}; the bell or the bow is steeper than the model treats accurately.</div>`;

397 return html;

398}

399

400// ---------- Simulation control ----------

401

402async function start(): Promise<void> {

403 if (!device || !plate) return;

404 player.stop();

405 running = false;

406 await new Promise((r) => setTimeout(r, 0));

407 sim?.destroy();

408 spec.reset();

409 live = true;

410 paused = false;

411 btnPause.textContent = "Pause";

412 params.duration = duration;

413 try {

414 sim = new Simulation(device, plate, params);

415 } catch (e) {

416 $("info").innerHTML = `<div class="err">Could not start: ${String(e)}</div>`;

417 return;

418 }

419 const hr = thicknessRange(plate);

420 renderer?.setField(sim.grid, sim.w0, sim.nw, sim.hn, sim.w0Max, [hr.min, hr.max]);

421 previewMode = false;

422 movieBuf?.destroy();

423 movieBuf = device.createBuffer({ size: Math.max(16, sim.grid.n * 4), usage: GPUBufferUsage.STORAGE | GPUBufferUsage.COPY_DST });

424 movieBufFrame = -1;

425 scrub.max = "0"; scrub.value = "0";

426 lastStatsTime = performance.now(); lastStatsSteps = 0; stepsPerSec = 0;

427 setEditable(false);

428 updateLiveButton();

429 void runLoop();

430}

431

432async function runLoop(): Promise<void> {

433 if (!sim || running) return;

434 running = true;

435 updateButtons();

436 try {

437 while (sim.phase !== "done" && !paused) {

438 await sim.runBatch();

439 spec.update(sim.recordedAudio(), sim.samples);

440 scrub.max = String(Math.max(0, sim.frames.length - 1));

441 if (live) scrub.value = scrub.max;

442 updateLevelReadout();

443 const now = performance.now();

444 if (now - lastStatsTime > 500) {

445 stepsPerSec = ((sim.totalSteps - lastStatsSteps) * 1000) / (now - lastStatsTime);

446 lastStatsTime = now; lastStatsSteps = sim.totalSteps;

447 }

448 }

449 } catch (e) {

450 console.error(e);

451 $("info").innerHTML = `<div class="err">Simulation error: ${String(e)}</div>`;

452 }

453 running = false;

454 if (sim.phase === "done") setEditable(true);

455 updateButtons();

456}

457

458// ---------- Render loop ----------

459

460let frameErrorShown = false;

461let lastRenderKey = "";

462let lastInfoHtml = "";

463

464function frame(): void {

465 requestAnimationFrame(frame);

466 try {

467 frameBody();

468 } catch (e) {

469 if (!frameErrorShown) { frameErrorShown = true; console.error("frame exception:", e); }

470 }

471}

472

473function markers(pl: Plate): void {

474 if (!renderer) return;

475 const [sx, sy] = strikePoint(params, pl);

476 renderer.strike = { x: sx, y: sy, r: params.contactRadius };

477 renderer.mount = pl.mount ? { x: pl.mount.x, y: pl.mount.y, r: pl.mount.radius } : null;

478}

479

480function frameBody(): void {

481 if (!device || !renderer) return;

482 renderer.mode = viewMode.value;

483 renderer.colorMode = colorSel.value as ColorMode;

484 renderer.exaggeration = parseFloat(exagInput.value) || 1;

485 renderer.colorRange = (parseFloat(rangeInput.value) || 0) * 1e-3;

486 renderer.showShape = shapeCheck.checked;

487 const canvas = $<HTMLCanvasElement>("view");

488 const cam = renderer.camera;

489 const viewKey = [

490 renderer.mode, renderer.colorMode, renderer.exaggeration, renderer.colorRange, renderer.showShape,

491 cam.yaw.toFixed(4), cam.pitch.toFixed(4), cam.dist.toFixed(4),

492 canvas.clientWidth, canvas.clientHeight, window.devicePixelRatio,

493 params.strikeFracX, params.strikeFracY, params.contactRadius,

494 ];

495 if (previewMode || !sim) {

496 // The stress-free shape of the design that the next Start will use.

497 ensurePreview(device);

498 const renderKey = ["preview", ...viewKey, preview?.plate.name, preview?.plate.grid.n].join("|");

499 if (renderKey !== lastRenderKey) {

500 lastRenderKey = renderKey;

501 renderPreview(device);

502 }

503 if (sim) {

504 spec.draw($("spec"), sim.fs, Math.max(duration, sim.samples / sim.fs), null);

505 updateInfo(sim.status());

506 }

507 return;

508 }

509 const pos = player.position();

510 if (pos !== null) {

511 scrubFrame = Math.min(sim.frames.length - 1, Math.floor(pos * sim.fps));

512 scrub.value = String(scrubFrame);

513 }

514 const st = sim.status();

515 // Render only when something visible changed, so an idle or paused page does no work.

516 const renderKey = [...viewKey, live, scrubFrame, sim.frames.length, st.totalSteps, st.phase].join("|");

517 if (renderKey !== lastRenderKey) {

518 lastRenderKey = renderKey;

519 renderView(device, st);

520 }

521 spec.draw($("spec"), sim.fs, Math.max(duration, sim.samples / sim.fs), pos ?? (live ? null : scrubFrame / sim.fps));

522 updateInfo(st);

523}

524

525/** Builds the preview buffers from the current plate when they are missing or stale. */

526function ensurePreview(dev: GPUDevice): void {

527 if (preview && !preview.stale) return;

528 if (!plate) return;

529 if (preview) for (const b of [preview.w0, preview.zero, preview.nw, preview.hn]) b.destroy();

530 const grid = plate.grid;

531 const shape = Float32Array.from(plate.w0);

532 let wmax = 0;

533 for (let k = 0; k < shape.length; k++) wmax = Math.max(wmax, Math.abs(shape[k]));

534 const mk = (data: Float32Array<ArrayBuffer>) => {

535 const b = dev.createBuffer({ size: Math.max(16, data.byteLength), usage: GPUBufferUsage.STORAGE | GPUBufferUsage.COPY_DST });

536 dev.queue.writeBuffer(b, 0, data);

537 return b;

538 };

539 preview = { plate, w0: mk(shape), zero: mk(new Float32Array(grid.n)), nw: mk(nodeWeights(grid)), hn: mk(Float32Array.from(plate.h)), wmax, stale: false };

540 const hr = thicknessRange(plate);

541 renderer?.setField(grid, preview.zero, preview.nw, preview.hn, 0, [hr.min, hr.max]);

542 lastRenderKey = "";

543}

544

545/** Marks the preview stale (the design or the spacing changed) and shows it; the next frame rebuilds it. */

546function showPreview(): void {

547 if (preview) preview.stale = true;

548 previewMode = true;

549 updateLiveButton();

550 if (!sim) updateIdleInfo();

551}

552

553function renderPreview(dev: GPUDevice): void {

554 if (!renderer || !preview) return;

555 // The renderer's "initial shape" buffer is zero here, and the shape itself is the displayed field.

556 if (renderer.fieldGrid !== preview.plate.grid) {

557 const hr = thicknessRange(preview.plate);

558 renderer.setField(preview.plate.grid, preview.zero, preview.nw, preview.hn, 0, [hr.min, hr.max]);

559 }

560 markers(preview.plate);

561 const enc = dev.createCommandEncoder();

562 renderer.render(enc, preview.w0, preview.wmax);

563 timeLabel.textContent = "design";

564 dev.pushErrorScope("validation");

565 dev.queue.submit([enc.finish()]);

566 void dev.popErrorScope().then((e) => { if (e && !frameErrorShown) { frameErrorShown = true; console.error("frame validation error:", e.message); } });

567}

568

569function updateIdleInfo(): void {

570 const html = plate

571 ? `<p class="sub">The view shows the design's stress-free shape.</p>`

572 : `<p class="err">${plateError ?? "No design."}</p>`;

573 if (html !== lastInfoHtml) {

574 lastInfoHtml = html;

575 $("info").innerHTML = html;

576 }

577}

578

579function renderView(dev: GPUDevice, st: SimStatus): void {

580 if (!sim || !renderer) return;

581 if (renderer.fieldGrid !== sim.grid) {

582 const hr = thicknessRange(sim.plate);

583 renderer.setField(sim.grid, sim.w0, sim.nw, sim.hn, sim.w0Max, [hr.min, hr.max]);

584 }

585 markers(sim.plate);

586 const enc = dev.createCommandEncoder();

587 if (live || sim.frames.length === 0) {

588 sim.encodeDisplay(enc);

589 renderer.render(enc, sim.displayW, st.wmax);

590 timeLabel.textContent = `${st.t.toFixed(3)} s`;

591 } else {

592 const f = Math.max(0, Math.min(sim.frames.length - 1, scrubFrame));

593 if (movieBufFrame !== f) {

594 dev.queue.writeBuffer(movieBuf!, 0, sim.frames[f]);

595 movieBufFrame = f;

596 }

597 let wmax = 0;

598 const fr = sim.frames[f];

599 for (let k = 0; k < fr.length; k += 7) wmax = Math.max(wmax, Math.abs(fr[k]));

600 renderer.render(enc, movieBuf!, wmax);

601 timeLabel.textContent = `${(f / sim.fps).toFixed(3)} s`;

602 }

603 dev.pushErrorScope("validation");

604 dev.queue.submit([enc.finish()]);

605 void dev.popErrorScope().then((e) => { if (e && !frameErrorShown) { frameErrorShown = true; console.error("frame validation error:", e.message); } });

606}

607

608function updateInfo(st: SimStatus): void {

609 if (!sim) return;

610 const g = sim.grid;

611 const spl = st.peakPressure > 0 ? 20 * Math.log10(st.peakPressure / 2e-5) : -Infinity;

612 const rows: [string, string][] = [

613 ["Design", sim.plate.name],

614 ["Phase", st.phase === "done" ? "done" : "ringing (recording)"],

615 ["Time", `${st.t.toFixed(3)} s`],

616 ["Grid", `${g.nx} × ${g.ny} nodes (${countInside(g)} in the plate), ${(g.hx * 1e3).toFixed(2)} × ${(g.hy * 1e3).toFixed(2)} mm`],

617 ["Time step", `${(sim.dt * 1e6).toFixed(3)} µs (${sim.stepsPerSample} per sample)`],

618 ["Speed", `${(stepsPerSec / 1e3).toFixed(0)} k steps/s (${(stepsPerSec * sim.dt).toFixed(3)}× real time)`],

619 ["Kinetic energy", `${st.ke.toExponential(2)} J`],

620 ["Max |w|", `${(st.wmax * 1e3).toFixed(3)} mm`],

621 ["Audio", `${(st.samples / sim.fs).toFixed(2)} s, ${st.frames} frames`],

622 ["Peak pressure", st.peakPressure > 0 ? `${st.peakPressure.toFixed(3)} Pa (${spl.toFixed(1)} dB SPL)` : "–"],

623 ["Stick", `${(st.stick.x * 1e3).toFixed(2)} mm, ${st.stick.v.toFixed(2)} m/s`],

624 ["Contact force", `${st.stick.force.toFixed(1)} N (max ${st.stick.maxForce.toFixed(1)} N)`],

625 ];

626 let html = rows.map(([a, b]) => `<div class="row"><span>${a}</span><span>${b}</span></div>`).join("");

627 if (st.delayClamped) html += `<div class="warn">The listener is so close that some propagation delays were clamped.</div>`;

628 if (!isFinite(st.wmax) || st.wmax > 1) html += `<div class="err">The solution has diverged. Increase the grid spacing (which lengthens the time step) or reduce the strike.</div>`;

629 if (html !== lastInfoHtml) {

630 lastInfoHtml = html;

631 $("info").innerHTML = html;

632 }

633}

634

635// ---------- Self-test ----------

636

637let selfTestResult: { done: boolean; passed?: boolean; cases?: SelfTestCase[]; error?: string } = { done: false };

638

639async function selfTest(): Promise<void> {

640 if (!device) { selfTestResult = { done: true, passed: false, error: "no GPU device" }; return; }

641 $("info").innerHTML = `<p class="sub">Running the GPU-versus-CPU self-test...</p>`;

642 try {

643 const cases = await runSelfTest(device);

644 const passed = cases.every(selfTestPassed);

645 selfTestResult = { done: true, passed, cases };

646 const rows = cases.map((c) => `<div class="row"><span>${c.name}</span><span class="${selfTestPassed(c) ? "" : "err"}">acc ${c.accError.u.toExponential(1)} / ${c.accError.v.toExponential(1)} / ${c.accError.w.toExponential(1)}, pos ${c.positionError.toExponential(1)}</span></div>`);

647 $("info").innerHTML = `<div class="${passed ? "row" : "err"}">Self-test ${passed ? "passed" : "FAILED"}</div>${rows.join("")}<p class="sub">Maximum relative errors of the u, v, w accelerations and of the compensated w update, GPU step versus float64 reference.</p>`;

648 } catch (e) {

649 selfTestResult = { done: true, passed: false, error: String(e) };

650 $("info").innerHTML = `<div class="err">Self-test error: ${String(e)}</div>`;

651 }

652}

653

654// ---------- Init ----------

655

656async function init(): Promise<void> {

657 editor = new DesignEditor($("design"));

658 form = new ParamForm($("params"), params);

659 form.onChange = (key, isLive) => {

660 if (key === "spacing") { rebuildPlate(); return; }

661 if (!isLive) { showPreview(); return; }

662 if (!sim) return;

663 if (key.startsWith("listener")) sim.setListener(params.listenerDist, params.listenerAzimuth, params.listenerElevation);

664 };

665 editor.onDesign = () => rebuildPlate();

666 buildSplitter();

667 buildControls();

668 buildViewToolbar();

669 buildMovieToolbar();

670 buildSpecToolbar();

671 const q = new URLSearchParams(location.search);

672 const set = form.applyUrl(q);

673 if (set.includes("duration")) {

674 duration = params.duration;

675 durInput.value = String(duration);

676 }

677 const presetId = q.get("preset");

678 const preset = presetId ? PRESETS.find((p) => p.id === presetId) : null;

679 if (preset) editor.setScript(preset.source, preset.id);

680 else editor.compileNow();

681 exposeHooks();

682 if (!("gpu" in navigator)) {

683 showNoGpu("WebGPU is not available in this browser. Use a recent Chrome or Edge, or Firefox or Safari with WebGPU enabled.");

684 return;

685 }

686 const adapter = (await navigator.gpu.requestAdapter({ powerPreference: "high-performance" })) ?? (await navigator.gpu.requestAdapter());

687 if (!adapter) {

688 showNoGpu("No WebGPU adapter was found.");

689 return;

690 }

691 device = await adapter.requestDevice();

692 device.lost.then((info) => showNoGpu(`WebGPU device lost: ${info.message}`));

693 device.addEventListener("uncapturederror", (ev) => console.error("WebGPU error:", (ev as GPUUncapturedErrorEvent).error.message));

694 renderer = new Renderer(device, $("view"));

695 updateIdleInfo();

696 updateButtons();

697 requestAnimationFrame(frame);

698 if (q.get("selftest") === "1") await selfTest();

699 else if (q.get("autostart") === "1") void start();

700}

701

702/** Hooks for automated tests, on window.steelsim. */

703function exposeHooks(): void {

704 (window as unknown as { steelsim: unknown }).steelsim = {

705 status: () => (sim ? { ...sim.status(), dt: sim.dt, stepsPerSample: sim.stepsPerSample, nx: sim.grid.nx, ny: sim.grid.ny, stepsPerSec } : null),

706 audio: () => (sim ? Array.from(sim.recordedAudio()) : null),

707 frames: () => sim?.frames.length ?? 0,

708 design: () => (plate ? { name: plate.name, nodes: countInside(plate.grid), mounted: !!plate.mount, error: null } : { name: null, nodes: 0, mounted: false, error: plateError }),

709 setScript: (source: string) => editor.setScript(source),

710 start: () => void start(),

711 selftest: () => selfTestResult,

712 noGpu: () => { const e = $("nogpu"); return e.hidden ? null : e.textContent; },

713 };

714}

715

716function showNoGpu(msg: string): void {

717 const el = $("nogpu");

718 el.hidden = false;

719 el.textContent = msg;

720 btnStart.disabled = true;

721 selfTestResult = { done: true, passed: false, error: msg };

722}

723

724void init();