code: public VirtualFlowHit<C> hit(double x, double y) {
          double bOff = orientation.getX(x, y);
          double lOff = orientation.getY(x, y);
  
          bOff += breadthOffset0.getValue();
  
          if(items.isEmpty()) {
              return orientation.hitAfterCells(bOff, lOff);
          }
  
          layout();
  
          int firstVisible = getFirstVisibleIndex();
          firstVisible = navigator.fillBackwardFrom0(firstVisible, lOff);
          C firstCell = cellPositioner.getVisibleCell(firstVisible);
  
          int lastVisible = getLastVisibleIndex();
          lastVisible = navigator.fillForwardFrom0(lastVisible, lOff);
          C lastCell = cellPositioner.getVisibleCell(lastVisible);
  
          if(lOff < orientation.minY(firstCell)) {
              return orientation.hitBeforeCells(bOff, lOff - orientation.minY(firstCell));
          } else if(lOff >= orientation.maxY(lastCell)) {
              return orientation.hitAfterCells(bOff, lOff - orientation.maxY(lastCell));
          } else {
              for(int i = firstVisible; i <= lastVisible; ++i) {
                  C cell = cellPositioner.getVisibleCell(i);
                  if(lOff < orientation.maxY(cell)) {
                      return orientation.cellHit(i, cell, bOff, lOff - orientation.minY(cell));
                  }
              }
              throw new AssertionError("unreachable code");
          }
      }
docs: Hits this virtual flow at the given coordinates.
  
  @param x x offset from the left edge of the viewport
  @param y y offset from the top edge of the viewport
  @return hit info containing the cell that was hit and coordinates
  relative to the cell. If the hit was before the cells (i.e. above a
  vertical flow content or left of a horizontal flow content), returns
  a <em>hit before cells</em> containing offset from the top left corner
  of the content. If the hit was after the cells (i.e. below a vertical
  flow content or right of a horizontal flow content), returns a
  <em>hit after cells</em> containing offset from the top right corner of
  the content of a horizontal flow or bottom left corner of the content of
  a vertical flow.