hdc (HDC) - input

Device context handle.

pptlPel (PPOINTL) - input

Pointer to the coordinate (X, Y) pair structure.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

rc (LONG) - returns

Return Code.

This function must return the color index value for the pel, or CLR_NOINDEX if there is no index corresponding to the color. In addition, the handling routine must raise an error when the point is subject to any clipping.

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_BITMAP_NOT_SELECTED 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
PMERR_PEL_IS_CLIPPED
PMERR_PEL_NOT_AVAILABLE

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