code: private function writeDrawings(XMLWriter $objWriter = null, PhpspreadsheetWorksheet $pSheet = null, $includeCharts = false)
      {
          $chartCount = ($includeCharts) ? $pSheet->getChartCollection()->count() : 0;
          // If sheet contains drawings, add the relationships
          if (($pSheet->getDrawingCollection()->count() > 0) ||
              ($chartCount > 0)) {
              $objWriter->startElement('drawing');
              $objWriter->writeAttribute('r:id', 'rId1');
              $objWriter->endElement();
          }
      }
docs: Write Drawings.
  
  @param XMLWriter $objWriter XML Writer
  @param PhpspreadsheetWorksheet $pSheet Worksheet
  @param bool $includeCharts Flag indicating if we should include drawing details for charts