GreQueryWidthTable

GreQueryWidthTable stores, at the location addressed by paWidthTable, an array of world coordinates representing the width-table information of the currently selected font.

This function must be supported by the presentation driver. GreQueryWidthTable is called by the function GpiQueryWidthTable.

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

Syntax

GreQueryWidthTable(hdc, lFirstChar, cWidthTable,
      paWidthTable, pInstance, lFunction)

Parameters

hdc (HDC) - input: Device context handle.
lFirstChar (LONG) - input: Code point of the initial character for which width-table information is required.
cWidthTable (LONG) - input: Count of widths in the width-table data.
paWidthTable (PLONG) - input: Pointer to buffer of width-table data.
pInstance (PVOID) - input: Pointer to instance data.
lFunction (ULONG) - input: High-order WORD=flags; low-order WORD=NGreQueryWidthTable.

Return Code

rc (BOOL) - returns

Return Code.

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_COORDINATE_OVERFLOW
PMERR_DEV_FUNC_NOT_INSTALLED
PMERR_EXCEEDS_MAX_SEG_LENGTH
PMERR_HDC_BUSY
PMERR_INSUFFICIENT_MEMORY
PMERR_INV_CHAR_MODE_ATTR
PMERR_INV_CODEPAGE
PMERR_INV_COORD_SPACE
PMERR_INV_FIRST_CHAR
PMERR_INV_HDC
PMERR_INV_LENGTH_OR_COUNT
PMERR_INV_MATRIX_ELEMENT
PMERR_INV_SETID
PMERR_INV_TRANSFORM_TYPE

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

Remarks

The handling routine must use GreConvert (see GreConvert) to transform the width-table information from device coordinates to world coordinates.

Sample Code

#define INCL_GRE_STRINGS
#include <os2.h>

HDC      hdc;           /*  Device context handle. */
LONG     lFirstChar;    /*  Code point of the initial character for which width-table
                            information is required. */
LONG     cWidthTable;   /*  Count of widths in the width-table data. */
PLONG    paWidthTable;  /*  Pointer to buffer of width-table data. */
PVOID    pInstance;     /*  Pointer to instance data. */
ULONG    lFunction;     /*  High-order WORD=flags; low-order WORD=NGreQueryWidthTable. */
BOOL     rc;            /*  Return Code. */

rc = GreQueryWidthTable(hdc, lFirstChar, cWidthTable,
       paWidthTable, pInstance, lFunction);