enum GridLineType { kInvalidGridLine = 0x00, kHorzTop = 0x01, kHorzInside = 0x02, kHorzBottom = 0x04, kVertLeft = 0x08, kVertInside = 0x10, kVertRight = 0x20, kHorzGridLineTypes = kHorzTop|kHorzBottom|kHorzInside, kVertGridLineTypes = kVertLeft|kVertRight|kVertInside, kOuterGridLineTypes = kHorzTop|kHorzBottom|kVertLeft|kVertRight, kInnerGridLineTypes = kHorzInside|kVertInside, kAllGridLineTypes = kOuterGridLineTypes|kInnerGridLineTypes };