GreConvertWithMatrix

GreConvertWithMatrix converts a series of points by using the indicated matrix. Other current transform matrixes are ignored.

This function can be hooked by the presentation driver.

Simulation support

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

Syntax

GreConvertWithMatrix(hdc, paptlPoint, cPoints, paXform, pInstance, lFunction);

Parameters

hdc (HDC) - input

Device context handle.

paptlPoint (PPOINTL) - input

Pointer to array of (X,Y) coordinates to transform. The result is also returned to this parameter.

cPoints (LONG) - input

Count of coordinate pairs in the array.

paXform (PXFORM) - input

Pointer to an array of six matrix elements for two-dimensional formation. These are M11, M12, M21, M22, M41, and M42.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

Returns

fSuccess (BOOL) - returns

This function returns BOOLEAN (fSuccess).

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_COORDINATE_OVERFLOW
• PMERR_INV_LENGTH_OR_COUNT

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

Sample

#define INCL_GRE_XFORMS
#include <os2.h>

HDC        hdc;         /*  Device context handle. */
PPOINTL    paptlPoint;
LONG       cPoints;     /*  Count of coordinate pairs in the array. */
PXFORM     paXform;
PVOID      pInstance;   /*  Pointer to instance data. */
ULONG      lFunction;   /*  High-order WORD=flags; low-order WORD=NGreConvertWithMatrix. */
BOOL       fSuccess;    /*  This function returns BOOLEAN (fSuccess). */

fSuccess = GreConvertWithMatrix(hdc, paptlPoint,
             cPoints, paXform, pInstance,
             lFunction);