GreDisjointLines

GreDisjointLines draws a sequence of disjoint straight lines using the end-point pairs specified. If COM_TRANSFORM is not set, the pairs are expected in screen coordinates.

This function is supported by the graphics engine and can be hooked by the presentation driver.

Simulation support: None. This function is mandatory for all drivers.

Syntax

GreDisjointLines(hdc, paptlPoint, cPoints, pInstance, lFunction, rc)

Parameters

hdc (HDC) - input: Device context handle.
paptlPoint (PPOINTL) - input: Pointer to an array of cPoints (X,Y) pairs.; Pointer to an array of cPoints (X,Y) pairs containing the end-points for the lines.
cPoints (LONG) - input: Number of (X,Y) pairs in the points array.; When this is passed as 0, the handling routine takes no action except to return Success.
pInstance (PVOID) - input: Pointer to instance data.
lFunction (ULONG) - input: High-order WORD=flags; low-order WORD=NGreDisjointLines.

Returns

rc (LONG)

Return Codes.

On completion, the handling routine must return an integer (cHits) indicating, where appropriate, whether correlation hits were detected:

GPI_OK Successful
GPI_HITS Successful with correlation hit (returned by display drivers when the correlation flag is ON, and a hit is detected)
GPI_ERROR Error

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_BASE_ERROR
PMERR_BITMAP_NOT_SELECTED
PMERR_COORDINATE_OVERFLOW
PMERR_DEV_FUNC_NOT_INSTALLED
PMERR_HDC_BUSY
PMERR_INV_COLOR_DATA
PMERR_INV_COLOR_INDEX
PMERR_INV_COORD_SPACE
PMERR_INV_HDC
PMERR_INV_IN_AREA
PMERR_INV_IN_PATH
PMERR_INV_LENGTH_OR_COUNT
PMERR_INV_PICK_APERTURE_POSN
PMERR_INV_RECT
PMERR_PATH_LIMIT_EXCEEDED
PMERR_PATH_UNKNOWN

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

Sample

#define INCL_GRE_LINES
#include <os2.h>

HDC        hdc;         /*  Device context handle. */
PPOINTL    paptlPoint;  /*  Pointer to an array of cPoints (X,Y) pairs. */
LONG       cPoints;     /*  Number of (X,Y) pairs in the points array. */
PVOID      pInstance;   /*  Pointer to instance data. */
ULONG      lFunction;
LONG       rc;          /*  Return Codes. */

GreDisjointLines(hdc, paptlPoint, cPoints, pInstance, lFunction, rc);