Function isTimedElementVisibleAt

packages/core/src/runtime/init.ts:513–550

(rawNode: HTMLElement, currentTime: number)

  };

  const isTimedElementVisibleAt = (rawNode: HTMLElement, currentTime: number): boolean => {
    const tag = rawNode.tagName.toLowerCase();
    if (tag === "script" || tag === "style" || tag === "link" || tag === "meta") {
      return false;
    }

    const start =
      tag === "video" || tag === "audio"
        ? resolveMediaStartSeconds(rawNode, 0)
        : resolveStartForElement(rawNode, 0);
    let duration = resolveDurationForElement(rawNode);
    const compId = rawNode.getAttribute("data-composition-id");
    if (compId) {
      const compTimeline = (window.__timelines ?? {})[compId];
      let liveDuration: number | null = null;
      if (compTimeline && typeof compTimeline.duration === "function") {
        const compDur = Number(compTimeline.duration());
        if (Number.isFinite(compDur) && compDur > 0) {
          liveDuration = compDur;
        }
      }

      const hasAuthoredTiming =
        rawNode.hasAttribute("data-duration") ||
        rawNode.hasAttribute("data-end") ||
        rawNode.hasAttribute(AUTHORED_DURATION_ATTR) ||
        rawNode.hasAttribute(AUTHORED_END_ATTR);

      if (!hasAuthoredTiming && (duration == null || duration <= 0) && liveDuration != null) {
        duration = liveDuration;
      }
    }
    const computedEnd =
      duration != null && duration > 0 ? start + duration : Number.POSITIVE_INFINITY;
    return (
      currentTime >= start && (Number.isFinite(computedEnd) ? currentTime <= computedEnd : true)
    );
  };

  const hasExternalCompositions = !!document.querySelector("[data-composition-src]");
  let hasInlineTemplateCompositions = false;