[This is preliminary documentation and subject to change.]
The GetMouseMovePoints function retrieves a history of up to 64 previous coordinates of the mouse or pen.
int GetMouseMovePoints(
UINT cbSize // size of the MOUSEMOVEPOINT struct
LPMOUSEMOVEPOINT lppt, // pointer to current mouse move point
LPMOUSEMOVEPOINT lpptBuf, // buffer to store the points
int nBufPoints, // how many points the buffer can store
DWORD resolution // resolution of the points
);
The GetMouseMovePoints function searches for the point in the mouse coordinates history. If the function finds the point, it returns the last nBufPoints prior to and including the supplied point.
If your application supplies a time stamp, the GetMouseMovePoints function will use it to differentiate between two equal points that were recorded at different times.
An application should call this function using the mouse coordinates received from the WM_MOUSEMOVE message and convert them to screen coordinates.
| Value | Meaning |
|---|---|
| GMMP_USE_DISPLAY_POINTS | Retrieves the points using the display resolution. |
| GMMP_USE_DRIVER_POINTS | Retrieves the points using the driver resolution. The Windows CE platform supports pen drivers with a resolution much higher than the display resolution. In this case, GetMouseMovePoints can be used by applications (such as handwriting recognition software or computer-aided design software) that need a much more accurate resolution. |
If the function succeeds, the return value is the number of points in the buffer. Otherwise, the function returns –1. For extended error information, your application can call GetLastError. The GetLastError function may return the following error code.
| Value | Meaning |
|---|---|
| GMMP_ERR_POINT_NOT_FOUND | The point specified by lppt is could not be found or is no longer in the system buffer. |
The system retains the last 64 mouse coordinates and their time stamps. If your application supplies a mouse coordinate to GetMouseMovePoints and the coordinate exists in the system's mouse coordinate history, the function retrieves the specified number of coordinates from the systems' history. You can also supply a time stamp, which will be used to differentiate between identical points in the history.
The GetMouseMovePoints function will return points that eventually were dispatched not only to the calling thread but also to other threads.
Windows NT: Requires version 5.0 or later.
Windows: Requires Windows 98.
Windows CE: Requires version 2.0 or later.
Header: Declared in winuser.h.
Import Library: Use user32.lib.
Mouse Input Overview, Mouse Input Functions, MOUSEMOVEPOINT