public void Rot90(bool changeFlags = true)
{
int gridX = BrushUtil.GetGridX(-Offset, m_brushTilemap.CellSize);
int gridY = BrushUtil.GetGridY(-Offset, m_brushTilemap.CellSize);
Offset = -new Vector2(gridY * m_brushTilemap.CellSize.x, (m_brushTilemap.GridWidth - gridX - 1) * m_brushTilemap.CellSize.y);
m_brushTilemap.Rot90(changeFlags);
m_brushTilemap.UpdateMeshImmediate();
}