Method scanElementSubtree

src/ink/ink.tsx:1071–1101

Paint an EXISTING DOM subtree to a fresh Screen at its natural * height, scan for query. Returns positions relative to the element's * bounding box (row 0 = element top). * * The element comes from the MAIN tree — built with all real * providers, yoga already computed. We paint it

(el: dom.DOMElement)

   *
   *  ~1-2ms (paint only, no reconcile — the DOM is already built). */
  scanElementSubtree(el: dom.DOMElement): MatchPosition[] {
    if (!this.searchHighlightQuery || !el.yogaNode) return [];
    const width = Math.ceil(el.yogaNode.getComputedWidth());
    const height = Math.ceil(el.yogaNode.getComputedHeight());
    if (width <= 0 || height <= 0) return [];
    // renderNodeToOutput adds el's OWN computedLeft/Top to offsetX/Y.
    // Passing -elLeft/-elTop nets to 0 → paints at (0,0) in our buffer.
    const elLeft = el.yogaNode.getComputedLeft();
    const elTop = el.yogaNode.getComputedTop();
    const screen = createScreen(width, height, this.stylePool, this.charPool, this.hyperlinkPool);
    const output = new Output({
      width,
      height,
      stylePool: this.stylePool,
      screen
    });
    renderNodeToOutput(el, output, {
      offsetX: -elLeft,
      offsetY: -elTop,
      prevScreen: undefined
    });
    const rendered = output.get();
    // renderNodeToOutput wrote our offset positions to nodeCache —
    // corrupts the main render (it'd blit from wrong coords). Mark the
    // subtree dirty so the next main render repaints + re-caches
    // correctly. One extra paint of this message, but correct > fast.
    dom.markDirty(el);
    const positions = scanPositions(rendered, this.searchHighlightQuery);
    logForDebugging(`scanElementSubtree: q='${this.searchHighlightQuery}' ` + `el=${width}x${height}@(${elLeft},${elTop}) n=${positions.length} ` + `[${positions.slice(0, 10).map(p => `${p.row}:${p.col}`).join(',')}` + `${positions.length > 10 ? ',…' : ''}]`);
    return positions;
  }

  /** Set the position-based highlight state. Every frame, writes CURRENT
   *  style at positions[currentIdx] + rowOffset. null clears. The scan-