OutputBase.Write 会为每个清洁单元发出一个 Cursor 定位调用,使每次重绘都需要执行 rows × cols 次系统调用。

for (int j = num; j < cols; j++)
{
    lastCol = -1;
    int outputWidth = 0;
    for (; j < cols; j++)
    {
        bool flag3 = IsRasterCoveredBlankCell(buffer, i, j, rasterCellRectangles);
        if (!buffer.Contents[i, j].IsDirty | flag3)          // cell is CLEAN
        {
            if (flag3) { buffer.Contents[i, j].IsDirty = false; }
            if (stringBuilder.Length > 0)
                WriteToConsole(stringBuilder, ref lastCol, ref outputWidth);
            else if (lastCol == -1)
                lastCol = j;
            if (lastCol + 1 < cols) { lastCol++; }
            SetCursorPositionImpl(lastCol, i);               // ← one I/O op per skipped cell
            continue;
        }
        // ...
    }
}