Refactor broadcast page

This commit is contained in:
2026-01-09 00:15:07 +01:00
parent 81c078d95f
commit 773021c456
9 changed files with 1077 additions and 955 deletions

View File

@@ -1,958 +1,6 @@
import { isAudioAsset } from "./media/audio.js"; import { BroadcastRenderer } from "./broadcast/renderer.js";
const canvas = document.getElementById("broadcast-canvas"); const canvas = document.getElementById("broadcast-canvas");
const obsBrowser = !!globalThis.obsstudio; const renderer = new BroadcastRenderer({ canvas, broadcaster, showToast });
const supportsAnimatedDecode =
typeof ImageDecoder !== "undefined" && typeof createImageBitmap === "function" && !obsBrowser;
const canPlayProbe = document.createElement("video");
const ctx = canvas.getContext("2d");
let canvasSettings = { width: 1920, height: 1080 };
const assets = new Map();
const mediaCache = new Map();
const renderStates = new Map();
const visibilityStates = new Map();
const animatedCache = new Map();
const blobCache = new Map();
const animationFailures = new Map();
const audioControllers = new Map();
const videoPlaybackStates = new WeakMap();
const pendingAudioUnlock = new Set();
const TARGET_FPS = 60;
const MIN_FRAME_TIME = 1000 / TARGET_FPS;
const VISIBILITY_THRESHOLD = 0.01;
let lastRenderTime = 0;
let frameScheduled = false;
let pendingDraw = false;
let renderIntervalId = null;
const audioUnlockEvents = ["pointerdown", "keydown", "touchstart"];
let layerOrder = [];
function spawnUserJavaScriptWorker() {} renderer.start();
function stopUserJavaScriptWorker() {}
applyCanvasSettings(canvasSettings);
audioUnlockEvents.forEach((eventName) => {
globalThis.addEventListener(eventName, () => {
if (!pendingAudioUnlock.size) return;
pendingAudioUnlock.forEach((controller) => safePlay(controller));
pendingAudioUnlock.clear();
});
});
function ensureLayerPosition(assetId, placement = "keep") {
const asset = assets.get(assetId);
if (asset && (isAudioAsset(asset) || isCodeAsset(asset))) {
return;
}
const existingIndex = layerOrder.indexOf(assetId);
if (existingIndex !== -1 && placement === "keep") {
return;
}
if (existingIndex !== -1) {
layerOrder.splice(existingIndex, 1);
}
if (placement === "append") {
layerOrder.push(assetId);
} else {
layerOrder.unshift(assetId);
}
layerOrder = layerOrder.filter((id) => assets.has(id));
}
function getLayerOrder() {
layerOrder = layerOrder.filter((id) => {
const asset = assets.get(id);
return asset && !isAudioAsset(asset) && !isCodeAsset(asset);
});
assets.forEach((asset, id) => {
if (isAudioAsset(asset) || isCodeAsset(asset)) {
return;
}
if (!layerOrder.includes(id)) {
layerOrder.unshift(id);
}
});
return layerOrder;
}
function getRenderOrder() {
return [...getLayerOrder()]
.reverse()
.map((id) => assets.get(id))
.filter(Boolean);
}
function removeAsset(assetId) {
assets.delete(assetId);
layerOrder = layerOrder.filter((id) => id !== assetId);
clearMedia(assetId);
stopUserJavaScriptWorker(assetId);
renderStates.delete(assetId);
visibilityStates.delete(assetId);
}
function connect() {
const socket = new SockJS("/ws");
const stompClient = Stomp.over(socket);
stompClient.connect({}, () => {
stompClient.subscribe(`/topic/channel/${broadcaster}`, (payload) => {
const body = JSON.parse(payload.body);
handleEvent(body);
});
fetch(`/api/channels/${broadcaster}/assets`)
.then((r) => {
if (!r.ok) {
throw new Error("Failed to load assets");
}
return r.json();
})
.then(renderAssets)
.catch(() => showToast("Unable to load overlay assets. Retrying may help.", "error"));
});
}
function renderAssets(list) {
layerOrder = [];
list.forEach((asset) => {
storeAsset(asset, "append");
if (isCodeAsset(asset)) {
spawnUserJavaScriptWorker(asset);
}
});
draw();
}
function storeAsset(asset, placement = "keep") {
if (!asset) return;
console.info(`Storing asset: ${asset.id}`);
const wasExisting = assets.has(asset.id);
assets.set(asset.id, asset);
ensureLayerPosition(asset.id, placement);
if (!wasExisting && !visibilityStates.has(asset.id)) {
const initialAlpha = 0; // Fade in newly discovered assets
visibilityStates.set(asset.id, { alpha: initialAlpha, targetHidden: !!asset.hidden });
}
}
async function fetchCanvasSettings() {
return fetch(`/api/channels/${encodeURIComponent(broadcaster)}/canvas`)
.then((r) => {
if (!r.ok) {
throw new Error("Failed to load canvas");
}
return r.json();
})
.then((settings) => {
applyCanvasSettings(settings);
})
.catch(() => {
resizeCanvas();
showToast("Using default canvas size. Unable to load saved settings.", "warning");
});
}
function applyCanvasSettings(settings) {
if (!settings) {
return;
}
const width = Number.isFinite(settings.width) ? settings.width : canvasSettings.width;
const height = Number.isFinite(settings.height) ? settings.height : canvasSettings.height;
canvasSettings = { width, height };
resizeCanvas();
}
function resizeCanvas() {
if (Number.isFinite(canvasSettings.width) && Number.isFinite(canvasSettings.height)) {
canvas.width = canvasSettings.width;
canvas.height = canvasSettings.height;
canvas.style.width = `${canvasSettings.width}px`;
canvas.style.height = `${canvasSettings.height}px`;
}
draw();
}
function handleEvent(event) {
if (event.type === "CANVAS" && event.payload) {
applyCanvasSettings(event.payload);
return;
}
const assetId = event.assetId || event?.patch?.id || event?.payload?.id;
if (event.type === "VISIBILITY") {
handleVisibilityEvent(event);
return;
}
if (event.type === "DELETED") {
removeAsset(assetId);
} else if (event.patch) {
applyPatch(assetId, event.patch);
if (event.payload) {
const payload = normalizePayload(event.payload);
if (payload.hidden) {
hideAssetWithTransition(payload);
} else if (!assets.has(payload.id)) {
upsertVisibleAsset(payload, "append");
}
}
} else if (event.type === "PLAY" && event.payload) {
const payload = normalizePayload(event.payload);
storeAsset(payload);
if (isAudioAsset(payload)) {
handleAudioPlay(payload, event.play !== false);
}
} else if (event.payload && !event.payload.hidden) {
const payload = normalizePayload(event.payload);
upsertVisibleAsset(payload);
} else if (event.payload && event.payload.hidden) {
hideAssetWithTransition(event.payload);
}
draw();
}
function normalizePayload(payload) {
return { ...payload };
}
function hideAssetWithTransition(asset) {
const payload = asset ? normalizePayload(asset) : null;
if (!payload?.id) {
return;
}
const existing = assets.get(payload.id);
if (
!existing &&
(!Number.isFinite(payload.x) ||
!Number.isFinite(payload.y) ||
!Number.isFinite(payload.width) ||
!Number.isFinite(payload.height))
) {
return;
}
const merged = normalizePayload({ ...(existing || {}), ...payload, hidden: true });
storeAsset(merged);
stopUserJavaScriptWorker(merged.id);
stopAudio(payload.id);
}
function upsertVisibleAsset(asset, placement = "keep") {
const payload = asset ? normalizePayload(asset) : null;
if (!payload?.id) {
return;
}
const placementMode = assets.has(payload.id) ? "keep" : placement;
storeAsset(payload, placementMode);
ensureMedia(payload);
if (isAudioAsset(payload)) {
playAudioImmediately(payload);
} else if (isCodeAsset(payload)) {
spawnUserJavaScriptWorker(payload);
}
}
function handleVisibilityEvent(event) {
const payload = event.payload ? normalizePayload(event.payload) : null;
const patch = event.patch;
const id = payload?.id || patch?.id || event.assetId;
if (payload?.hidden || patch?.hidden) {
hideAssetWithTransition({ id, ...payload, ...patch });
draw();
return;
}
if (payload) {
const placement = assets.has(payload.id) ? "keep" : "append";
upsertVisibleAsset(payload, placement);
}
if (patch && id) {
applyPatch(id, patch);
}
draw();
}
function applyPatch(assetId, patch) {
if (!assetId || !patch) {
return;
}
const sanitizedPatch = Object.fromEntries(
Object.entries(patch).filter(([, value]) => value !== null && value !== undefined),
);
const existing = assets.get(assetId);
if (!existing) {
return;
}
const merged = normalizePayload({ ...existing, ...sanitizedPatch });
console.log(merged);
const isAudio = isAudioAsset(merged);
if (sanitizedPatch.hidden) {
hideAssetWithTransition(merged);
return;
}
const targetLayer = Number.isFinite(patch.layer)
? patch.layer
: Number.isFinite(patch.zIndex)
? patch.zIndex
: null;
if (!isAudio && Number.isFinite(targetLayer)) {
const currentOrder = getLayerOrder().filter((id) => id !== assetId);
const insertIndex = Math.max(0, currentOrder.length - Math.round(targetLayer));
currentOrder.splice(insertIndex, 0, assetId);
layerOrder = currentOrder;
}
storeAsset(merged);
ensureMedia(merged);
if (isCodeAsset(merged)) {
console.info(`Spawning JS worker for patched asset: ${merged.id}`);
spawnUserJavaScriptWorker(merged);
}
}
function draw() {
if (frameScheduled) {
pendingDraw = true;
return;
}
frameScheduled = true;
requestAnimationFrame((timestamp) => {
const elapsed = timestamp - lastRenderTime;
const delay = MIN_FRAME_TIME - elapsed;
const shouldRender = elapsed >= MIN_FRAME_TIME;
if (shouldRender) {
lastRenderTime = timestamp;
renderFrame();
}
frameScheduled = false;
if (pendingDraw || !shouldRender) {
pendingDraw = false;
setTimeout(draw, Math.max(0, delay));
}
});
}
function renderFrame() {
ctx.clearRect(0, 0, canvas.width, canvas.height);
getRenderOrder().forEach(drawAsset);
}
function drawAsset(asset) {
const visibility = getVisibilityState(asset);
if (visibility.alpha <= VISIBILITY_THRESHOLD && asset.hidden) {
return;
}
const renderState = smoothState(asset);
const halfWidth = renderState.width / 2;
const halfHeight = renderState.height / 2;
ctx.save();
ctx.globalAlpha = Math.max(0, Math.min(1, visibility.alpha));
ctx.translate(renderState.x + halfWidth, renderState.y + halfHeight);
ctx.rotate((renderState.rotation * Math.PI) / 180);
if (isCodeAsset(asset)) {
ctx.restore();
return;
}
if (isAudioAsset(asset)) {
if (!asset.hidden) {
autoStartAudio(asset);
}
ctx.restore();
return;
}
const media = ensureMedia(asset);
const drawSource = media?.isAnimated ? media.bitmap : media;
const ready = isDrawable(media);
if (ready && drawSource) {
ctx.drawImage(drawSource, -halfWidth, -halfHeight, renderState.width, renderState.height);
}
ctx.restore();
}
function getVisibilityState(asset) {
const current = visibilityStates.get(asset.id) || {};
const targetAlpha = asset.hidden ? 0 : 1;
const startingAlpha = Number.isFinite(current.alpha) ? current.alpha : 0;
const factor = asset.hidden ? 0.18 : 0.2;
const nextAlpha = lerp(startingAlpha, targetAlpha, factor);
const state = { alpha: nextAlpha, targetHidden: !!asset.hidden };
visibilityStates.set(asset.id, state);
return state;
}
function smoothState(asset) {
const previous = renderStates.get(asset.id) || { ...asset };
const factor = 0.15;
const next = {
x: lerp(previous.x, asset.x, factor),
y: lerp(previous.y, asset.y, factor),
width: lerp(previous.width, asset.width, factor),
height: lerp(previous.height, asset.height, factor),
rotation: smoothAngle(previous.rotation, asset.rotation, factor),
};
renderStates.set(asset.id, next);
return next;
}
function smoothAngle(current, target, factor) {
const delta = ((target - current + 180) % 360) - 180;
return current + delta * factor;
}
function lerp(a, b, t) {
return a + (b - a) * t;
}
function queueAudioForUnlock(controller) {
if (!controller) return;
pendingAudioUnlock.add(controller);
}
function safePlay(controller) {
if (!controller?.element) return;
const playPromise = controller.element.play();
if (playPromise?.catch) {
playPromise.catch(() => queueAudioForUnlock(controller));
}
}
function recordDuration(assetId, seconds) {
if (!Number.isFinite(seconds) || seconds <= 0) {
return;
}
const asset = assets.get(assetId);
if (!asset) {
return;
}
const nextMs = Math.round(seconds * 1000);
if (asset.durationMs === nextMs) {
return;
}
asset.durationMs = nextMs;
}
function isVideoAsset(asset) {
if (asset?.assetType) {
return asset.assetType === "VIDEO";
}
return asset?.mediaType?.startsWith("video/");
}
function getVideoPlaybackState(element) {
if (!element) {
return { playRequested: false, unmuteOnPlay: false };
}
let state = videoPlaybackStates.get(element);
if (!state) {
state = { playRequested: false, unmuteOnPlay: false };
videoPlaybackStates.set(element, state);
}
return state;
}
function isCodeAsset(asset) {
if (asset?.assetType) {
return asset.assetType === "SCRIPT";
}
const type = (asset?.mediaType || asset?.originalMediaType || "").toLowerCase();
return type.startsWith("application/javascript") || type.startsWith("text/javascript");
}
function isVideoElement(element) {
return element?.tagName === "VIDEO";
}
function isGifAsset(asset) {
return asset?.mediaType?.toLowerCase() === "image/gif";
}
function isDrawable(element) {
if (!element) {
return false;
}
if (element.isAnimated) {
return !!element.bitmap;
}
if (isVideoElement(element)) {
return element.readyState >= 2;
}
if (typeof ImageBitmap !== "undefined" && element instanceof ImageBitmap) {
return true;
}
return !!element.complete;
}
function clearMedia(assetId) {
const element = mediaCache.get(assetId);
if (isVideoElement(element)) {
element.src = "";
element.remove();
}
mediaCache.delete(assetId);
const animated = animatedCache.get(assetId);
if (animated) {
animated.cancelled = true;
clearTimeout(animated.timeout);
animated.bitmap?.close?.();
animated.decoder?.close?.();
animatedCache.delete(assetId);
}
animationFailures.delete(assetId);
const cachedBlob = blobCache.get(assetId);
if (cachedBlob?.objectUrl) {
URL.revokeObjectURL(cachedBlob.objectUrl);
}
blobCache.delete(assetId);
const audio = audioControllers.get(assetId);
if (audio) {
if (audio.delayTimeout) {
clearTimeout(audio.delayTimeout);
}
audio.element.pause();
audio.element.currentTime = 0;
audio.element.src = "";
audio.element.remove();
audioControllers.delete(assetId);
}
}
function ensureAudioController(asset) {
const cached = audioControllers.get(asset.id);
if (cached && cached.src === asset.url) {
applyAudioSettings(cached, asset);
return cached;
}
if (cached) {
clearMedia(asset.id);
}
const element = new Audio(asset.url);
element.autoplay = true;
element.preload = "auto";
element.controls = false;
element.addEventListener("loadedmetadata", () => recordDuration(asset.id, element.duration));
const controller = {
id: asset.id,
src: asset.url,
element,
delayTimeout: null,
loopEnabled: false,
loopActive: true,
delayMs: 0,
baseDelayMs: 0,
};
element.onended = () => handleAudioEnded(asset.id);
audioControllers.set(asset.id, controller);
applyAudioSettings(controller, asset, true);
return controller;
}
function applyAudioSettings(controller, asset, resetPosition = false) {
controller.loopEnabled = !!asset.audioLoop;
controller.loopActive = controller.loopEnabled && controller.loopActive !== false;
controller.baseDelayMs = Math.max(0, asset.audioDelayMillis || 0);
controller.delayMs = controller.baseDelayMs;
applyAudioElementSettings(controller.element, asset);
if (resetPosition) {
controller.element.currentTime = 0;
controller.element.pause();
}
}
function applyAudioElementSettings(element, asset) {
const speed = Math.max(0.25, asset.audioSpeed || 1);
const pitch = Math.max(0.5, asset.audioPitch || 1);
element.playbackRate = speed * pitch;
const volume = Math.max(0, Math.min(2, asset.audioVolume ?? 1));
element.volume = Math.min(volume, 1);
}
function getAssetVolume(asset) {
return Math.max(0, Math.min(2, asset?.audioVolume ?? 1));
}
function applyMediaVolume(element, asset) {
if (!element) return 1;
const volume = getAssetVolume(asset);
element.volume = Math.min(volume, 1);
return volume;
}
function handleAudioEnded(assetId) {
const controller = audioControllers.get(assetId);
if (!controller) return;
controller.element.currentTime = 0;
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
}
if (controller.loopEnabled && controller.loopActive) {
controller.delayTimeout = setTimeout(() => {
safePlay(controller);
}, controller.delayMs);
} else {
controller.element.pause();
}
}
function stopAudio(assetId) {
const controller = audioControllers.get(assetId);
if (!controller) return;
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
}
controller.element.pause();
controller.element.currentTime = 0;
controller.delayTimeout = null;
controller.delayMs = controller.baseDelayMs;
controller.loopActive = false;
}
function playAudioImmediately(asset) {
const controller = ensureAudioController(asset);
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
controller.delayTimeout = null;
}
controller.element.currentTime = 0;
const originalDelay = controller.delayMs;
controller.delayMs = 0;
safePlay(controller);
controller.delayMs = controller.baseDelayMs ?? originalDelay ?? 0;
}
function playOverlappingAudio(asset) {
const temp = new Audio(asset.url);
temp.autoplay = true;
temp.preload = "auto";
temp.controls = false;
applyAudioElementSettings(temp, asset);
const controller = { element: temp };
temp.onended = () => {
temp.remove();
};
safePlay(controller);
}
function handleAudioPlay(asset, shouldPlay) {
const controller = ensureAudioController(asset);
controller.loopActive = !!shouldPlay;
if (!shouldPlay) {
stopAudio(asset.id);
return;
}
if (asset.audioLoop) {
controller.delayMs = controller.baseDelayMs;
safePlay(controller);
} else {
playOverlappingAudio(asset);
}
}
function autoStartAudio(asset) {
if (!isAudioAsset(asset) || asset.hidden) {
return;
}
const controller = ensureAudioController(asset);
if (!controller.loopEnabled || !controller.loopActive) {
return;
}
if (!controller.element.paused && !controller.element.ended) {
return;
}
if (controller.delayTimeout) {
return;
}
controller.delayTimeout = setTimeout(() => {
safePlay(controller);
}, controller.delayMs);
}
function ensureMedia(asset) {
const cached = mediaCache.get(asset.id);
const cachedSource = getCachedSource(cached);
if (cached && cachedSource !== asset.url) {
clearMedia(asset.id);
}
if (cached && cachedSource === asset.url) {
applyMediaSettings(cached, asset);
return cached;
}
if (isAudioAsset(asset)) {
ensureAudioController(asset);
mediaCache.delete(asset.id);
return null;
}
if (isGifAsset(asset) && supportsAnimatedDecode) {
const animated = ensureAnimatedImage(asset);
if (animated) {
mediaCache.set(asset.id, animated);
return animated;
}
}
const element = isVideoAsset(asset) ? document.createElement("video") : new Image();
element.dataset.sourceUrl = asset.url;
element.crossOrigin = "anonymous";
if (isVideoElement(element)) {
if (!canPlayVideoType(asset.mediaType)) {
return null;
}
element.loop = true;
element.playsInline = true;
element.autoplay = true;
element.controls = false;
element.onloadeddata = draw;
element.onloadedmetadata = () => recordDuration(asset.id, element.duration);
element.preload = "auto";
element.addEventListener("error", () => clearMedia(asset.id));
const playbackState = getVideoPlaybackState(element);
element.addEventListener("playing", () => {
playbackState.playRequested = false;
if (playbackState.unmuteOnPlay) {
element.muted = false;
playbackState.unmuteOnPlay = false;
}
});
element.addEventListener("pause", () => {
playbackState.playRequested = false;
});
applyMediaVolume(element, asset);
element.muted = true;
setVideoSource(element, asset);
} else {
element.onload = draw;
element.src = asset.url;
}
mediaCache.set(asset.id, element);
return element;
}
function ensureAnimatedImage(asset) {
const failedAt = animationFailures.get(asset.id);
if (failedAt && Date.now() - failedAt < 15000) {
return null;
}
const cached = animatedCache.get(asset.id);
if (cached && cached.url === asset.url) {
return cached;
}
animationFailures.delete(asset.id);
if (cached) {
clearMedia(asset.id);
}
const controller = {
id: asset.id,
url: asset.url,
src: asset.url,
decoder: null,
bitmap: null,
timeout: null,
cancelled: false,
isAnimated: true,
};
fetchAssetBlob(asset)
.then((blob) => new ImageDecoder({ data: blob, type: blob.type || "image/gif" }))
.then((decoder) => {
if (controller.cancelled) {
decoder.close?.();
return null;
}
controller.decoder = decoder;
scheduleNextFrame(controller);
return controller;
})
.catch(() => {
animatedCache.delete(asset.id);
animationFailures.set(asset.id, Date.now());
});
animatedCache.set(asset.id, controller);
return controller;
}
function fetchAssetBlob(asset) {
const cached = blobCache.get(asset.id);
if (cached && cached.url === asset.url && cached.blob) {
return Promise.resolve(cached.blob);
}
if (cached && cached.url === asset.url && cached.pending) {
return cached.pending;
}
const pending = fetch(asset.url)
.then((r) => r.blob())
.then((blob) => {
const previous = blobCache.get(asset.id);
const existingUrl = previous?.url === asset.url ? previous.objectUrl : null;
const objectUrl = existingUrl || URL.createObjectURL(blob);
blobCache.set(asset.id, { url: asset.url, blob, objectUrl });
return blob;
});
blobCache.set(asset.id, { url: asset.url, pending });
return pending;
}
function setVideoSource(element, asset) {
if (!shouldUseBlobUrl(asset)) {
applyVideoSource(element, asset.url, asset);
return;
}
const cached = blobCache.get(asset.id);
if (cached?.url === asset.url && cached.objectUrl) {
applyVideoSource(element, cached.objectUrl, asset);
return;
}
fetchAssetBlob(asset)
.then(() => {
const next = blobCache.get(asset.id);
if (next?.url !== asset.url || !next.objectUrl) {
return;
}
applyVideoSource(element, next.objectUrl, asset);
})
.catch(() => {});
}
function applyVideoSource(element, objectUrl, asset) {
element.src = objectUrl;
startVideoPlayback(element, asset);
}
function shouldUseBlobUrl(asset) {
return !obsBrowser && asset?.mediaType && canPlayVideoType(asset.mediaType);
}
function canPlayVideoType(mediaType) {
if (!mediaType) {
return true;
}
const support = canPlayProbe.canPlayType(mediaType);
return support === "probably" || support === "maybe";
}
function getCachedSource(element) {
return element?.dataset?.sourceUrl || element?.src;
}
function scheduleNextFrame(controller) {
if (controller.cancelled || !controller.decoder) {
return;
}
controller.decoder
.decode()
.then(({ image, complete }) => {
if (controller.cancelled) {
image.close?.();
return;
}
controller.bitmap?.close?.();
createImageBitmap(image)
.then((bitmap) => {
controller.bitmap = bitmap;
draw();
})
.finally(() => image.close?.());
const durationMicros = image.duration || 0;
const delay = durationMicros > 0 ? durationMicros / 1000 : 100;
const hasMore = !complete;
controller.timeout = setTimeout(() => {
if (controller.cancelled) {
return;
}
if (hasMore) {
scheduleNextFrame(controller);
} else {
controller.decoder.reset();
scheduleNextFrame(controller);
}
}, delay);
})
.catch(() => {
// If decoding fails, clear animated cache so static fallback is used next render
animatedCache.delete(controller.id);
animationFailures.set(controller.id, Date.now());
});
}
function applyMediaSettings(element, asset) {
if (!isVideoElement(element)) {
return;
}
startVideoPlayback(element, asset);
}
function startVideoPlayback(element, asset) {
const playbackState = getVideoPlaybackState(element);
const nextSpeed = asset.speed ?? 1;
const effectiveSpeed = Math.max(nextSpeed, 0.01);
if (element.playbackRate !== effectiveSpeed) {
element.playbackRate = effectiveSpeed;
}
const volume = applyMediaVolume(element, asset);
const shouldUnmute = volume > 0;
element.muted = true;
if (effectiveSpeed === 0) {
element.pause();
playbackState.playRequested = false;
playbackState.unmuteOnPlay = false;
return;
}
element.play();
if (shouldUnmute) {
if (!element.paused && element.readyState >= 2) {
element.muted = false;
} else {
playbackState.unmuteOnPlay = true;
}
}
if (element.paused || element.ended) {
if (!playbackState.playRequested) {
playbackState.playRequested = true;
const playPromise = element.play();
if (playPromise?.catch) {
playPromise.catch(() => {
playbackState.playRequested = false;
});
}
}
}
}
function startRenderLoop() {
if (renderIntervalId) {
return;
}
renderIntervalId = setInterval(() => {
draw();
}, MIN_FRAME_TIME);
}
globalThis.addEventListener("resize", () => {
resizeCanvas();
});
fetchCanvasSettings().finally(() => {
resizeCanvas();
startRenderLoop();
connect();
});

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import { isAudioAsset } from "../media/audio.js";
import { AssetKind } from "./constants.js";
export function isCodeAsset(asset) {
if (asset?.assetType) {
return asset.assetType === "SCRIPT";
}
const type = (asset?.mediaType || asset?.originalMediaType || "").toLowerCase();
return type.startsWith("application/javascript") || type.startsWith("text/javascript");
}
export function isVideoAsset(asset) {
if (asset?.assetType) {
return asset.assetType === "VIDEO";
}
return asset?.mediaType?.startsWith("video/");
}
export function isVideoElement(element) {
return element?.tagName === "VIDEO";
}
export function isGifAsset(asset) {
return asset?.mediaType?.toLowerCase() === "image/gif";
}
export function getAssetKind(asset) {
if (isAudioAsset(asset)) {
return AssetKind.AUDIO;
}
if (isCodeAsset(asset)) {
return AssetKind.CODE;
}
return AssetKind.VISUAL;
}
export function isVisualAsset(asset) {
return getAssetKind(asset) === AssetKind.VISUAL;
}

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const audioUnlockEvents = ["pointerdown", "keydown", "touchstart"];
export function createAudioManager({ assets, globalScope = globalThis }) {
const audioControllers = new Map();
const pendingAudioUnlock = new Set();
audioUnlockEvents.forEach((eventName) => {
globalScope.addEventListener(eventName, () => {
if (!pendingAudioUnlock.size) return;
pendingAudioUnlock.forEach((controller) => safePlay(controller, pendingAudioUnlock));
pendingAudioUnlock.clear();
});
});
function ensureAudioController(asset) {
const cached = audioControllers.get(asset.id);
if (cached && cached.src === asset.url) {
applyAudioSettings(cached, asset);
return cached;
}
if (cached) {
clearAudio(asset.id);
}
const element = new Audio(asset.url);
element.autoplay = true;
element.preload = "auto";
element.controls = false;
element.addEventListener("loadedmetadata", () => recordDuration(asset.id, element.duration));
const controller = {
id: asset.id,
src: asset.url,
element,
delayTimeout: null,
loopEnabled: false,
loopActive: true,
delayMs: 0,
baseDelayMs: 0,
};
element.onended = () => handleAudioEnded(asset.id);
audioControllers.set(asset.id, controller);
applyAudioSettings(controller, asset, true);
return controller;
}
function applyAudioSettings(controller, asset, resetPosition = false) {
controller.loopEnabled = !!asset.audioLoop;
controller.loopActive = controller.loopEnabled && controller.loopActive !== false;
controller.baseDelayMs = Math.max(0, asset.audioDelayMillis || 0);
controller.delayMs = controller.baseDelayMs;
applyAudioElementSettings(controller.element, asset);
if (resetPosition) {
controller.element.currentTime = 0;
controller.element.pause();
}
}
function applyAudioElementSettings(element, asset) {
const speed = Math.max(0.25, asset.audioSpeed || 1);
const pitch = Math.max(0.5, asset.audioPitch || 1);
element.playbackRate = speed * pitch;
const volume = Math.max(0, Math.min(2, asset.audioVolume ?? 1));
element.volume = Math.min(volume, 1);
}
function getAssetVolume(asset) {
return Math.max(0, Math.min(2, asset?.audioVolume ?? 1));
}
function applyMediaVolume(element, asset) {
if (!element) return 1;
const volume = getAssetVolume(asset);
element.volume = Math.min(volume, 1);
return volume;
}
function handleAudioEnded(assetId) {
const controller = audioControllers.get(assetId);
if (!controller) return;
controller.element.currentTime = 0;
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
}
if (controller.loopEnabled && controller.loopActive) {
controller.delayTimeout = setTimeout(() => {
safePlay(controller, pendingAudioUnlock);
}, controller.delayMs);
} else {
controller.element.pause();
}
}
function stopAudio(assetId) {
const controller = audioControllers.get(assetId);
if (!controller) return;
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
}
controller.element.pause();
controller.element.currentTime = 0;
controller.delayTimeout = null;
controller.delayMs = controller.baseDelayMs;
controller.loopActive = false;
}
function playAudioImmediately(asset) {
const controller = ensureAudioController(asset);
if (controller.delayTimeout) {
clearTimeout(controller.delayTimeout);
controller.delayTimeout = null;
}
controller.element.currentTime = 0;
const originalDelay = controller.delayMs;
controller.delayMs = 0;
safePlay(controller, pendingAudioUnlock);
controller.delayMs = controller.baseDelayMs ?? originalDelay ?? 0;
}
function playOverlappingAudio(asset) {
const temp = new Audio(asset.url);
temp.autoplay = true;
temp.preload = "auto";
temp.controls = false;
applyAudioElementSettings(temp, asset);
const controller = { element: temp };
temp.onended = () => {
temp.remove();
};
safePlay(controller, pendingAudioUnlock);
}
function handleAudioPlay(asset, shouldPlay) {
const controller = ensureAudioController(asset);
controller.loopActive = !!shouldPlay;
if (!shouldPlay) {
stopAudio(asset.id);
return;
}
if (asset.audioLoop) {
controller.delayMs = controller.baseDelayMs;
safePlay(controller, pendingAudioUnlock);
} else {
playOverlappingAudio(asset);
}
}
function autoStartAudio(asset) {
if (asset.hidden) {
return;
}
const controller = ensureAudioController(asset);
if (!controller.loopEnabled || !controller.loopActive) {
return;
}
if (!controller.element.paused && !controller.element.ended) {
return;
}
if (controller.delayTimeout) {
return;
}
controller.delayTimeout = setTimeout(() => {
safePlay(controller, pendingAudioUnlock);
}, controller.delayMs);
}
function recordDuration(assetId, seconds) {
if (!Number.isFinite(seconds) || seconds <= 0) {
return;
}
const asset = assets.get(assetId);
if (!asset) {
return;
}
const nextMs = Math.round(seconds * 1000);
if (asset.durationMs === nextMs) {
return;
}
asset.durationMs = nextMs;
}
function clearAudio(assetId) {
const audio = audioControllers.get(assetId);
if (!audio) {
return;
}
if (audio.delayTimeout) {
clearTimeout(audio.delayTimeout);
}
audio.element.pause();
audio.element.currentTime = 0;
audio.element.src = "";
audio.element.remove();
audioControllers.delete(assetId);
}
return {
ensureAudioController,
applyMediaVolume,
handleAudioPlay,
stopAudio,
playAudioImmediately,
autoStartAudio,
clearAudio,
};
}
function safePlay(controller, pendingUnlock) {
if (!controller?.element) return;
const playPromise = controller.element.play();
if (playPromise?.catch) {
playPromise.catch(() => {
pendingUnlock.add(controller);
});
}
}

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export const TARGET_FPS = 60;
export const MIN_FRAME_TIME = 1000 / TARGET_FPS;
export const VISIBILITY_THRESHOLD = 0.01;
export const AssetKind = Object.freeze({
AUDIO: "audio",
CODE: "code",
VISUAL: "visual",
});

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import { isVisualAsset } from "./assetKinds.js";
export function ensureLayerPosition(state, assetId, placement = "keep") {
const asset = state.assets.get(assetId);
if (asset && !isVisualAsset(asset)) {
return;
}
const existingIndex = state.layerOrder.indexOf(assetId);
if (existingIndex !== -1 && placement === "keep") {
return;
}
if (existingIndex !== -1) {
state.layerOrder.splice(existingIndex, 1);
}
if (placement === "append") {
state.layerOrder.push(assetId);
} else {
state.layerOrder.unshift(assetId);
}
state.layerOrder = state.layerOrder.filter((id) => state.assets.has(id));
}
export function getLayerOrder(state) {
state.layerOrder = state.layerOrder.filter((id) => {
const asset = state.assets.get(id);
return asset && isVisualAsset(asset);
});
state.assets.forEach((asset, id) => {
if (!isVisualAsset(asset)) {
return;
}
if (!state.layerOrder.includes(id)) {
state.layerOrder.unshift(id);
}
});
return state.layerOrder;
}
export function getRenderOrder(state) {
return [...getLayerOrder(state)]
.reverse()
.map((id) => state.assets.get(id))
.filter(Boolean);
}

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import { isAudioAsset } from "../media/audio.js";
import { isGifAsset, isVideoAsset, isVideoElement } from "./assetKinds.js";
export function createMediaManager({
state,
audioManager,
draw,
obsBrowser,
supportsAnimatedDecode,
canPlayProbe,
}) {
const { mediaCache, animatedCache, blobCache, animationFailures, videoPlaybackStates } = state;
function clearMedia(assetId) {
const element = mediaCache.get(assetId);
if (isVideoElement(element)) {
element.src = "";
element.remove();
}
mediaCache.delete(assetId);
const animated = animatedCache.get(assetId);
if (animated) {
animated.cancelled = true;
clearTimeout(animated.timeout);
animated.bitmap?.close?.();
animated.decoder?.close?.();
animatedCache.delete(assetId);
}
animationFailures.delete(assetId);
const cachedBlob = blobCache.get(assetId);
if (cachedBlob?.objectUrl) {
URL.revokeObjectURL(cachedBlob.objectUrl);
}
blobCache.delete(assetId);
audioManager.clearAudio(assetId);
}
function ensureMedia(asset) {
const cached = mediaCache.get(asset.id);
const cachedSource = getCachedSource(cached);
if (cached && cachedSource !== asset.url) {
clearMedia(asset.id);
}
if (cached && cachedSource === asset.url) {
applyMediaSettings(cached, asset);
return cached;
}
if (isAudioAsset(asset)) {
audioManager.ensureAudioController(asset);
mediaCache.delete(asset.id);
return null;
}
if (isGifAsset(asset) && supportsAnimatedDecode) {
const animated = ensureAnimatedImage(asset);
if (animated) {
mediaCache.set(asset.id, animated);
return animated;
}
}
const element = isVideoAsset(asset) ? document.createElement("video") : new Image();
element.dataset.sourceUrl = asset.url;
element.crossOrigin = "anonymous";
if (isVideoElement(element)) {
if (!canPlayVideoType(asset.mediaType)) {
return null;
}
element.loop = true;
element.playsInline = true;
element.autoplay = true;
element.controls = false;
element.onloadeddata = draw;
element.onloadedmetadata = () => recordDuration(asset.id, element.duration);
element.preload = "auto";
element.addEventListener("error", () => clearMedia(asset.id));
const playbackState = getVideoPlaybackState(element);
element.addEventListener("playing", () => {
playbackState.playRequested = false;
if (playbackState.unmuteOnPlay) {
element.muted = false;
playbackState.unmuteOnPlay = false;
}
});
element.addEventListener("pause", () => {
playbackState.playRequested = false;
});
audioManager.applyMediaVolume(element, asset);
element.muted = true;
setVideoSource(element, asset);
} else {
element.onload = draw;
element.src = asset.url;
}
mediaCache.set(asset.id, element);
return element;
}
function ensureAnimatedImage(asset) {
const failedAt = animationFailures.get(asset.id);
if (failedAt && Date.now() - failedAt < 15000) {
return null;
}
const cached = animatedCache.get(asset.id);
if (cached && cached.url === asset.url) {
return cached;
}
animationFailures.delete(asset.id);
if (cached) {
clearMedia(asset.id);
}
const controller = {
id: asset.id,
url: asset.url,
src: asset.url,
decoder: null,
bitmap: null,
timeout: null,
cancelled: false,
isAnimated: true,
};
fetchAssetBlob(asset)
.then((blob) => new ImageDecoder({ data: blob, type: blob.type || "image/gif" }))
.then((decoder) => {
if (controller.cancelled) {
decoder.close?.();
return null;
}
controller.decoder = decoder;
scheduleNextFrame(controller);
return controller;
})
.catch(() => {
animatedCache.delete(asset.id);
animationFailures.set(asset.id, Date.now());
});
animatedCache.set(asset.id, controller);
return controller;
}
function fetchAssetBlob(asset) {
const cached = blobCache.get(asset.id);
if (cached && cached.url === asset.url && cached.blob) {
return Promise.resolve(cached.blob);
}
if (cached && cached.url === asset.url && cached.pending) {
return cached.pending;
}
const pending = fetch(asset.url)
.then((r) => r.blob())
.then((blob) => {
const previous = blobCache.get(asset.id);
const existingUrl = previous?.url === asset.url ? previous.objectUrl : null;
const objectUrl = existingUrl || URL.createObjectURL(blob);
blobCache.set(asset.id, { url: asset.url, blob, objectUrl });
return blob;
});
blobCache.set(asset.id, { url: asset.url, pending });
return pending;
}
function setVideoSource(element, asset) {
if (!shouldUseBlobUrl(asset)) {
applyVideoSource(element, asset.url, asset);
return;
}
const cached = blobCache.get(asset.id);
if (cached?.url === asset.url && cached.objectUrl) {
applyVideoSource(element, cached.objectUrl, asset);
return;
}
fetchAssetBlob(asset)
.then(() => {
const next = blobCache.get(asset.id);
if (next?.url !== asset.url || !next.objectUrl) {
return;
}
applyVideoSource(element, next.objectUrl, asset);
})
.catch(() => {});
}
function applyVideoSource(element, objectUrl, asset) {
element.src = objectUrl;
startVideoPlayback(element, asset);
}
function shouldUseBlobUrl(asset) {
return !obsBrowser && asset?.mediaType && canPlayVideoType(asset.mediaType);
}
function canPlayVideoType(mediaType) {
if (!mediaType) {
return true;
}
const support = canPlayProbe.canPlayType(mediaType);
return support === "probably" || support === "maybe";
}
function getCachedSource(element) {
return element?.dataset?.sourceUrl || element?.src;
}
function scheduleNextFrame(controller) {
if (controller.cancelled || !controller.decoder) {
return;
}
controller.decoder
.decode()
.then(({ image, complete }) => {
if (controller.cancelled) {
image.close?.();
return;
}
controller.bitmap?.close?.();
createImageBitmap(image)
.then((bitmap) => {
controller.bitmap = bitmap;
draw();
})
.finally(() => image.close?.());
const durationMicros = image.duration || 0;
const delay = durationMicros > 0 ? durationMicros / 1000 : 100;
const hasMore = !complete;
controller.timeout = setTimeout(() => {
if (controller.cancelled) {
return;
}
if (hasMore) {
scheduleNextFrame(controller);
} else {
controller.decoder.reset();
scheduleNextFrame(controller);
}
}, delay);
})
.catch(() => {
animatedCache.delete(controller.id);
animationFailures.set(controller.id, Date.now());
});
}
function applyMediaSettings(element, asset) {
if (!isVideoElement(element)) {
return;
}
startVideoPlayback(element, asset);
}
function startVideoPlayback(element, asset) {
const playbackState = getVideoPlaybackState(element);
const nextSpeed = asset.speed ?? 1;
const effectiveSpeed = Math.max(nextSpeed, 0.01);
if (element.playbackRate !== effectiveSpeed) {
element.playbackRate = effectiveSpeed;
}
const volume = audioManager.applyMediaVolume(element, asset);
const shouldUnmute = volume > 0;
element.muted = true;
if (effectiveSpeed === 0) {
element.pause();
playbackState.playRequested = false;
playbackState.unmuteOnPlay = false;
return;
}
element.play();
if (shouldUnmute) {
if (!element.paused && element.readyState >= 2) {
element.muted = false;
} else {
playbackState.unmuteOnPlay = true;
}
}
if (element.paused || element.ended) {
if (!playbackState.playRequested) {
playbackState.playRequested = true;
const playPromise = element.play();
if (playPromise?.catch) {
playPromise.catch(() => {
playbackState.playRequested = false;
});
}
}
}
}
function recordDuration(assetId, seconds) {
if (!Number.isFinite(seconds) || seconds <= 0) {
return;
}
const asset = state.assets.get(assetId);
if (!asset) {
return;
}
const nextMs = Math.round(seconds * 1000);
if (asset.durationMs === nextMs) {
return;
}
asset.durationMs = nextMs;
}
function getVideoPlaybackState(element) {
if (!element) {
return { playRequested: false, unmuteOnPlay: false };
}
let playbackState = videoPlaybackStates.get(element);
if (!playbackState) {
playbackState = { playRequested: false, unmuteOnPlay: false };
videoPlaybackStates.set(element, playbackState);
}
return playbackState;
}
return {
clearMedia,
ensureMedia,
applyMediaSettings,
canPlayVideoType,
};
}

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import { AssetKind, MIN_FRAME_TIME, VISIBILITY_THRESHOLD } from "./constants.js";
import { createBroadcastState } from "./state.js";
import { getAssetKind, isCodeAsset, isVisualAsset, isVideoElement } from "./assetKinds.js";
import { ensureLayerPosition, getLayerOrder, getRenderOrder } from "./layers.js";
import { getVisibilityState, smoothState } from "./visibility.js";
import { createAudioManager } from "./audioManager.js";
import { createMediaManager } from "./mediaManager.js";
export class BroadcastRenderer {
constructor({ canvas, broadcaster, showToast }) {
this.canvas = canvas;
this.ctx = canvas.getContext("2d");
this.broadcaster = broadcaster;
this.showToast = showToast;
this.state = createBroadcastState();
this.lastRenderTime = 0;
this.frameScheduled = false;
this.pendingDraw = false;
this.renderIntervalId = null;
this.obsBrowser = !!globalThis.obsstudio;
this.supportsAnimatedDecode =
typeof ImageDecoder !== "undefined" &&
typeof createImageBitmap === "function" &&
!this.obsBrowser;
this.canPlayProbe = document.createElement("video");
this.audioManager = createAudioManager({ assets: this.state.assets });
this.mediaManager = createMediaManager({
state: this.state,
audioManager: this.audioManager,
draw: () => this.draw(),
obsBrowser: this.obsBrowser,
supportsAnimatedDecode: this.supportsAnimatedDecode,
canPlayProbe: this.canPlayProbe,
});
this.applyCanvasSettings(this.state.canvasSettings);
globalThis.addEventListener("resize", () => {
this.resizeCanvas();
});
}
start() {
this.fetchCanvasSettings().finally(() => {
this.resizeCanvas();
this.startRenderLoop();
this.connect();
});
}
connect() {
const socket = new SockJS("/ws");
const stompClient = Stomp.over(socket);
stompClient.connect({}, () => {
stompClient.subscribe(`/topic/channel/${this.broadcaster}`, (payload) => {
const body = JSON.parse(payload.body);
this.handleEvent(body);
});
fetch(`/api/channels/${this.broadcaster}/assets`)
.then((r) => {
if (!r.ok) {
throw new Error("Failed to load assets");
}
return r.json();
})
.then((assets) => this.renderAssets(assets))
.catch(() =>
this.showToast("Unable to load overlay assets. Retrying may help.", "error"),
);
});
}
renderAssets(list) {
this.state.layerOrder = [];
list.forEach((asset) => {
this.storeAsset(asset, "append");
if (isCodeAsset(asset)) {
this.spawnUserJavaScriptWorker(asset);
}
});
this.draw();
}
storeAsset(asset, placement = "keep") {
if (!asset) return;
console.info(`Storing asset: ${asset.id}`);
const wasExisting = this.state.assets.has(asset.id);
this.state.assets.set(asset.id, asset);
ensureLayerPosition(this.state, asset.id, placement);
if (!wasExisting && !this.state.visibilityStates.has(asset.id)) {
const initialAlpha = 0; // Fade in newly discovered assets
this.state.visibilityStates.set(asset.id, {
alpha: initialAlpha,
targetHidden: !!asset.hidden,
});
}
}
removeAsset(assetId) {
this.state.assets.delete(assetId);
this.state.layerOrder = this.state.layerOrder.filter((id) => id !== assetId);
this.mediaManager.clearMedia(assetId);
this.stopUserJavaScriptWorker(assetId);
this.state.renderStates.delete(assetId);
this.state.visibilityStates.delete(assetId);
}
async fetchCanvasSettings() {
return fetch(`/api/channels/${encodeURIComponent(this.broadcaster)}/canvas`)
.then((r) => {
if (!r.ok) {
throw new Error("Failed to load canvas");
}
return r.json();
})
.then((settings) => {
this.applyCanvasSettings(settings);
})
.catch(() => {
this.resizeCanvas();
this.showToast("Using default canvas size. Unable to load saved settings.", "warning");
});
}
applyCanvasSettings(settings) {
if (!settings) {
return;
}
const width = Number.isFinite(settings.width)
? settings.width
: this.state.canvasSettings.width;
const height = Number.isFinite(settings.height)
? settings.height
: this.state.canvasSettings.height;
this.state.canvasSettings = { width, height };
this.resizeCanvas();
}
resizeCanvas() {
if (
Number.isFinite(this.state.canvasSettings.width) &&
Number.isFinite(this.state.canvasSettings.height)
) {
this.canvas.width = this.state.canvasSettings.width;
this.canvas.height = this.state.canvasSettings.height;
this.canvas.style.width = `${this.state.canvasSettings.width}px`;
this.canvas.style.height = `${this.state.canvasSettings.height}px`;
}
this.draw();
}
handleEvent(event) {
if (event.type === "CANVAS" && event.payload) {
this.applyCanvasSettings(event.payload);
return;
}
const assetId = event.assetId || event?.patch?.id || event?.payload?.id;
if (event.type === "VISIBILITY") {
this.handleVisibilityEvent(event);
return;
}
if (event.type === "DELETED") {
this.removeAsset(assetId);
} else if (event.patch) {
this.applyPatch(assetId, event.patch);
if (event.payload) {
const payload = this.normalizePayload(event.payload);
if (payload.hidden) {
this.hideAssetWithTransition(payload);
} else if (!this.state.assets.has(payload.id)) {
this.upsertVisibleAsset(payload, "append");
}
}
} else if (event.type === "PLAY" && event.payload) {
const payload = this.normalizePayload(event.payload);
this.storeAsset(payload);
if (getAssetKind(payload) === AssetKind.AUDIO) {
this.audioManager.handleAudioPlay(payload, event.play !== false);
}
} else if (event.payload && !event.payload.hidden) {
const payload = this.normalizePayload(event.payload);
this.upsertVisibleAsset(payload);
} else if (event.payload && event.payload.hidden) {
this.hideAssetWithTransition(event.payload);
}
this.draw();
}
normalizePayload(payload) {
return { ...payload };
}
hideAssetWithTransition(asset) {
const payload = asset ? this.normalizePayload(asset) : null;
if (!payload?.id) {
return;
}
const existing = this.state.assets.get(payload.id);
if (
!existing &&
(!Number.isFinite(payload.x) ||
!Number.isFinite(payload.y) ||
!Number.isFinite(payload.width) ||
!Number.isFinite(payload.height))
) {
return;
}
const merged = this.normalizePayload({ ...(existing || {}), ...payload, hidden: true });
this.storeAsset(merged);
this.stopUserJavaScriptWorker(merged.id);
this.audioManager.stopAudio(payload.id);
}
upsertVisibleAsset(asset, placement = "keep") {
const payload = asset ? this.normalizePayload(asset) : null;
if (!payload?.id) {
return;
}
const placementMode = this.state.assets.has(payload.id) ? "keep" : placement;
this.storeAsset(payload, placementMode);
this.mediaManager.ensureMedia(payload);
const kind = getAssetKind(payload);
if (kind === AssetKind.AUDIO) {
this.audioManager.playAudioImmediately(payload);
} else if (kind === AssetKind.CODE) {
this.spawnUserJavaScriptWorker(payload);
}
}
handleVisibilityEvent(event) {
const payload = event.payload ? this.normalizePayload(event.payload) : null;
const patch = event.patch;
const id = payload?.id || patch?.id || event.assetId;
if (payload?.hidden || patch?.hidden) {
this.hideAssetWithTransition({ id, ...payload, ...patch });
this.draw();
return;
}
if (payload) {
const placement = this.state.assets.has(payload.id) ? "keep" : "append";
this.upsertVisibleAsset(payload, placement);
}
if (patch && id) {
this.applyPatch(id, patch);
}
this.draw();
}
applyPatch(assetId, patch) {
if (!assetId || !patch) {
return;
}
const sanitizedPatch = Object.fromEntries(
Object.entries(patch).filter(([, value]) => value !== null && value !== undefined),
);
const existing = this.state.assets.get(assetId);
if (!existing) {
return;
}
const merged = this.normalizePayload({ ...existing, ...sanitizedPatch });
console.log(merged);
const isVisual = isVisualAsset(merged);
if (sanitizedPatch.hidden) {
this.hideAssetWithTransition(merged);
return;
}
const targetLayer = Number.isFinite(patch.layer)
? patch.layer
: Number.isFinite(patch.zIndex)
? patch.zIndex
: null;
if (isVisual && Number.isFinite(targetLayer)) {
const currentOrder = getLayerOrder(this.state).filter((id) => id !== assetId);
const insertIndex = Math.max(0, currentOrder.length - Math.round(targetLayer));
currentOrder.splice(insertIndex, 0, assetId);
this.state.layerOrder = currentOrder;
}
this.storeAsset(merged);
this.mediaManager.ensureMedia(merged);
if (isCodeAsset(merged)) {
console.info(`Spawning JS worker for patched asset: ${merged.id}`);
this.spawnUserJavaScriptWorker(merged);
}
}
draw() {
if (this.frameScheduled) {
this.pendingDraw = true;
return;
}
this.frameScheduled = true;
requestAnimationFrame((timestamp) => {
const elapsed = timestamp - this.lastRenderTime;
const delay = MIN_FRAME_TIME - elapsed;
const shouldRender = elapsed >= MIN_FRAME_TIME;
if (shouldRender) {
this.lastRenderTime = timestamp;
this.renderFrame();
}
this.frameScheduled = false;
if (this.pendingDraw || !shouldRender) {
this.pendingDraw = false;
setTimeout(() => this.draw(), Math.max(0, delay));
}
});
}
renderFrame() {
this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
getRenderOrder(this.state).forEach((asset) => this.drawAsset(asset));
}
drawAsset(asset) {
const visibility = getVisibilityState(this.state, asset);
if (visibility.alpha <= VISIBILITY_THRESHOLD && asset.hidden) {
return;
}
const renderState = smoothState(this.state, asset);
const halfWidth = renderState.width / 2;
const halfHeight = renderState.height / 2;
this.ctx.save();
this.ctx.globalAlpha = Math.max(0, Math.min(1, visibility.alpha));
this.ctx.translate(renderState.x + halfWidth, renderState.y + halfHeight);
this.ctx.rotate((renderState.rotation * Math.PI) / 180);
const kind = getAssetKind(asset);
if (kind === AssetKind.CODE) {
this.ctx.restore();
return;
}
if (kind === AssetKind.AUDIO) {
if (!asset.hidden) {
this.audioManager.autoStartAudio(asset);
}
this.ctx.restore();
return;
}
const media = this.mediaManager.ensureMedia(asset);
const drawSource = media?.isAnimated ? media.bitmap : media;
const ready = this.isDrawable(media);
if (ready && drawSource) {
this.ctx.drawImage(drawSource, -halfWidth, -halfHeight, renderState.width, renderState.height);
}
this.ctx.restore();
}
isDrawable(element) {
if (!element) {
return false;
}
if (element.isAnimated) {
return !!element.bitmap;
}
if (isVideoElement(element)) {
return element.readyState >= 2;
}
if (typeof ImageBitmap !== "undefined" && element instanceof ImageBitmap) {
return true;
}
return !!element.complete;
}
startRenderLoop() {
if (this.renderIntervalId) {
return;
}
this.renderIntervalId = setInterval(() => {
this.draw();
}, MIN_FRAME_TIME);
}
spawnUserJavaScriptWorker() {}
stopUserJavaScriptWorker() {}
}

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@@ -0,0 +1,14 @@
export function createBroadcastState() {
return {
canvasSettings: { width: 1920, height: 1080 },
assets: new Map(),
mediaCache: new Map(),
renderStates: new Map(),
visibilityStates: new Map(),
animatedCache: new Map(),
blobCache: new Map(),
animationFailures: new Map(),
videoPlaybackStates: new WeakMap(),
layerOrder: [],
};
}

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export function getVisibilityState(state, asset) {
const current = state.visibilityStates.get(asset.id) || {};
const targetAlpha = asset.hidden ? 0 : 1;
const startingAlpha = Number.isFinite(current.alpha) ? current.alpha : 0;
const factor = asset.hidden ? 0.18 : 0.2;
const nextAlpha = lerp(startingAlpha, targetAlpha, factor);
const nextState = { alpha: nextAlpha, targetHidden: !!asset.hidden };
state.visibilityStates.set(asset.id, nextState);
return nextState;
}
export function smoothState(state, asset) {
const previous = state.renderStates.get(asset.id) || { ...asset };
const factor = 0.15;
const next = {
x: lerp(previous.x, asset.x, factor),
y: lerp(previous.y, asset.y, factor),
width: lerp(previous.width, asset.width, factor),
height: lerp(previous.height, asset.height, factor),
rotation: smoothAngle(previous.rotation, asset.rotation, factor),
};
state.renderStates.set(asset.id, next);
return next;
}
function smoothAngle(current, target, factor) {
const delta = ((target - current + 180) % 360) - 180;
return current + delta * factor;
}
function lerp(a, b, t) {
return a + (b - a) * t;
}