GreEqualRegion

GreEqualRegion checks whether two regions, owned by the device that is identified by hdc, are identical. An error is raised when either region is currently selected as the clip region.

This function can be hooked by the presentation driver.

Simulation support

This function is simulated by a handling routine in the graphics engine.

Syntax

GreEqualRegion(hdc, hrgnSrc1, hrgnSrc2, pInstance, lFunction)

Parameters

hdc (HDC) - input

Device context handle.

hrgnSrc1 (HRGN) - input

First region handle.

hrgnSrc2 (HRGN) - input

Second region handle.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

Returns

rc (LONG) - returns

Return codes.

This function returns an integer (lEquality) indicating whether the regions are equal:

• EQRGN_EQUAL Equal
• EQRGN_ERROR Error
• EQRGN_NOTEQUAL Not equal

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_HRGN_BUSY
• PMERR_INV_HRGN
• PMERR_REGION_IS_CLIP_REGION

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

Sample

#define INCL_GRE_REGIONS
#include <os2.h>

HDC      hdc;        /*  Device context handle. */
HRGN     hrgnSrc1;   /*  First region handle. */
HRGN     hrgnSrc2;   /*  Second region handle. */
PVOID    pInstance;  /*  Pointer to instance data. */
ULONG    lFunction;  /*  High-order WORD=flags; low-order WORD=NGreEqualRegion. */
LONG     rc;         /*  Return codes. */

rc = GreEqualRegion(hdc, hrgnSrc1, hrgnSrc2, pInstance, lFunction);