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);