This message sets the size of a tick mark for the primary scale. All tick marks are initially set to a size of 0 (invisible). Each tick mark along a scale can be set to the size desired.

param1
     USHORT  usTickNum   /*  Tick mark location. */
     USHORT  usTickSize  /*  Tick mark length. */

param2
     ULONG   ulReserved  /*  Reserved value, should be 0. */