GreDeviceSetDCOrigin

GreDeviceSetDCOrigin sets the origin of the device context which, when created, has its origin set to 1.0,0.

This function must be supported by presentation drivers for display devices and for hardcopy devices that use banding. The minimum requirement for other hardcopy devices is for the handling routine to return TRUE if the origin addressed by pptlDC is set to 0, or to log an error and return FALSE.

Simulation support

None. This function is mandatory for all drivers.

Syntax

GreDeviceSetDCOrigin(hdc, pptlDC, pInstance, lFunction)

Parameters

hdc (HDC) - input

Device context handle.

pptlDC (PPOINTL) - input

Pointer to the DC origin.

This is the offset to the origin of the device context indicated by hdc. Convert does not add in this offset (see GreConvert).

Therefore, the presentation driver must add it to all device coordinates to make them screen coordinates.

Note

WORLD_COORDINATE to SCREEN_COORDINATE is not a valid conversion.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

Return Code

rc (BOOL) - returns

Return Codes.

On completion, the handling routine must return a BOOLEAN value to indicate success or an error.

• TRUE Successful
• FALSE 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_DEV_FUNC_NOT_INSTALLED
• PMERR_INV_HDC

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

Sample Code

#define INCL_GRE_DEVMISC3
#include <os2.h>

HDC        hdc;        /*  Device context handle. */
PPOINTL    pptlDC;     /*  Pointer to the DC origin. */
PVOID      pInstance;  /*  Pointer to instance data. */
ULONG      lFunction;
BOOL       rc;         /*  Return Codes. */

rc = GreDeviceSetDCOrigin(hdc, pptlDC, pInstance, lFunction);