hdc (HDC) - input

Device context handle.

pptlPoint (PPOINTL) - input

Pointer to (X,Y) point in world or screen coordinates.

If COM_TRANSFORM is not set, the function expects the point to be in screen coordinates.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

High-order WORD=flags; low-order WORD=NGrePtVisible.

rc (LONG) - returns

Return codes.

This function returns an integer (lVisible) indicating the visibility of the point:

PVIS_ERROR

Error
PVIS_INVISIBLE
Not visible
PVIS_VISIBLE
Visible
Possible Errors Detected: When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:

PMERR_COORDINATE_OVERFLOW PMERR_DEV_FUNC_NOT_INSTALLED
PMERR_HDC_BUSY
PMERR_INV_COORD_SPACE
PMERR_INV_COORDINATE
PMERR_INV_HDC
PMERR_INV_LENGTH_OR_COUNT
PMERR_INV_RECT

Refer to the "Error Explanations" section in the Presentation Manager Programming Reference for further explanation.