PeekPenInput
2.0
Retrieves
information about a specified pen packet in the pen input queue. For a
definition of pen packet, see the description of SetPenHook.
int PeekPenInput( HPCM hpcm, UINT idEvent,
LPPOINT lppt, LPVOID lpvOem, UINT fuOemFlags
)
Parameters
hpcm
Handle to a
pen collection. This is the return value from StartPenInput.
idEvent
The
identifier of the packet to be retrieved. The idEvent is the low-order
word of the value returned from the Windows GetMessageExtraInfo function when processing a
WM_LBUTTONDOWN message.
lppt
Far pointer
to a POINT
structure. PeekPenInput copies the point corresponding to idEvent
into the buffer pointed to by lppt.
lpvOem
The address
of a buffer of OEM data in the packet. This parameter can be NULL if no OEM
data is required.
fuOemFlags
Flags
specifying which OEM data to retrieve. If this parameter is NULL, all of the
OEM data provided by the tablet is returned in the order specified by the rgoempeninfo
array in PENINFO.
These flags have an implicit order. For example, if pressure and barrel
rotation are specified in that order, cPntMax pairs of these data are
returned in the same order: [pressure, rotation], [pressure, rotation], and so
on. (cPntMax is the number of POINT structures specified in GetPenInput.)
|
Constant |
Description |
|
PHW_PRESSURE |
Retrieve
pressure data. |
|
PHW_HEIGHT |
Retrieve
height data. |
|
PHW_ANGLEXY |
Retrieve
data pertaining to the x- and y-coordinates. |
|
PHW_ANGLEZ |
Retrieve
data pertaining to the z-coordinates. |
|
PHW_BARRELROTATION |
Retrieve
barrel-rotation data. |
|
PHW_OEMSPECIFIC |
Retrieve
OEM-specific data. |
|
PHW_PDK |
Retrieve
PDK_ data. |
Return Value
Returns
PCMR_OK if successful; otherwise, the return value can be one of the following:
|
Constant |
Description |
|
PCMR_INVALIDCOLLECTION |
The hpcm
handle is invalid because the calling application did not start input with StartPenInput. |
|
PCMR_INVALID_PACKETID |
idEvent is invalid. |
Comments
Unlike GetPenInput, this function does not
remove data from the pen input queue. It only returns information about the
packet specified by idEvent.
Whereas lppt
points into the pen input queue, lpvOem does not. If lpvOem is
not NULL, it points to a buffer provided by the caller into which the OEM data
are copied from the pen input queue.
The buffer
that lpvOem points to must be large enough to hold the requested OEM
data copied from the packet. The size of each packet is the width specified in
the cbOemData member of the PENINFO structure, plus sizeof(
UINT ) if PDK_ values are required.
See Also