OnMouseWheel

This method is called as a user rotates the mouse wheel and encounters the wheel’s next notch.

HRESULT OnMouseWheel(

 [in] long Flags,

 [in] short zDelta,

 [in] int X,

 [in] int Y,

 [in, out] VARIANT* pbHandled)

Parameters:

• Flags – Indicates whether various virtual keys are down. This parameter can be any combination of the following values:

• MK_ LBUTTON    = 1

• MK_ RBUTTON    = 2

• MK_ SHIFT            = 4

• MK_CONTROL     = 8

• MK_ MBUTTON   = 16

• ZDelta – Indicates distance rotated. The zDelta value is expressed in multiples or divisions of WHEEL_DELTA, which is 120. A value less than zero indicates rotating back (toward the user) while a value greater than zero indicates rotating forward (away from the user). The user can reverse this response by changing the Wheel setting in the mouse software. See the Remarks for more information about this parameter.

• X – The X-coordinate of the mouse. The coordinates are given in screen coordinates, with the origin in the top-left corner of the 3D Window.

• Y – The Y-coordinate of the mouse. The coordinates are given in screen coordinates, with the origin in the top-left corner of the 3D Window.

• PbHandled – Setting this to TRUE informs TerraExplorer that the client handled the mouse action itself and does not wish TerraExplorer to respond to the mouse action. When the client sets this to FALSE, TerraExplorer handles the mouse action normally.