Vcl.Controls.TCMMouseWheel

 TCMMouseWheel = record
 Msg: Cardinal;
 MsgFiller: TDWordFiller;
 ShiftState: TShiftState;
 WheelDelta: SmallInt;
 ShiftStateWheel: TDWordFiller;
 case Integer of
 0: (
 XPos: Smallint;
 YPos: Smallint;
 XYPos: TDWordFiller);
 1: (
 Pos: TSmallPoint;
 PosFiller: TDWordFiller;
 Result: LRESULT);
 end;

struct DECLSPEC_DRECORD TCMMouseWheel
{
public:
 unsigned Msg;
#ifndef _WIN64
#else /* _WIN64 */
 Winapi::Messages::TDWordFiller MsgFiller;
#endif /* _WIN64 */
 System::Classes::TShiftState ShiftState;
 short WheelDelta;
#ifndef _WIN64
#else /* _WIN64 */
 Winapi::Messages::TDWordFiller ShiftStateWheel;
#endif /* _WIN64 */
public:
 union
 {
 struct
 {
 System::Types::TSmallPoint Pos;
#ifdef _WIN64
 Winapi::Messages::TDWordFiller PosFiller;
#endif /* _WIN64 */
 NativeInt Result;
 };
 struct
 {
 short XPos;
 short YPos;
#ifndef _WIN64
#else /* _WIN64 */
 Winapi::Messages::TDWordFiller XYPos;
#endif /* _WIN64 */
 };
 };
};