Jump to content

GreGetPairKerningTable: Difference between revisions

From EDM2
Created page with "GreGetPairKerningTable stores the kerning pairs of the current font to the buffer addressed by pKernPairs. This function must be supported by the presentation driver. The ca..."
 
Ak120 (talk | contribs)
35,819 edits
mNo edit summary
 
Line 1: Line 1:
GreGetPairKerningTable stores the kerning pairs of the current font to the buffer addressed by pKernPairs.  
GreGetPairKerningTable stores the kerning pairs of the current font to the buffer addressed by pKernPairs.


This function must be supported by the presentation driver. The call parameters are passed unchanged to the display driver's dispatch table. GreGetPairKerningTable is called from GpiQueryKerningPairs. GreGetPairKerningTable is used to return the kerning data for the currently selected font. This function can be handled by bit-map simulation.  
This function must be supported by the presentation driver. The call parameters are passed unchanged to the display driver's dispatch table. GreGetPairKerningTable is called from [[GpiQueryKerningPairs]]. GreGetPairKerningTable is used to return the kerning data for the currently selected font. This function can be handled by bit-map simulation.


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


== Syntax ==  
== Syntax ==
  GreGetPairKerningTable(hdc, cKernPairs, pKernPairs, pInstance, lFunction);
  GreGetPairKerningTable(hdc, cKernPairs, pKernPairs, pInstance, lFunction)


== Parameters ==
== Parameters ==
; hdc (HDC) - input : Device context handle.  
;hdc (HDC) - input : Device context handle.
 
;cKernPairs (LONG) - input : Number of kerning pairs requested by the application.
; cKernPairs (LONG) - input : Number of kerning pairs requested by the application.  
;pKernPairs (PKERNPAIRS) - input : Pointer to kerning pair records.
 
:KERNINGPAIRS data structure:
; pKernPairs (PKERNPAIRS) - input : Pointer to kerning pair records.  
:* sFirstChar Code point for the first character
:KERNINGPAIRS data structure:  
:* sSecondChar Code point for the second character
:* sFirstChar Code point for the first character  
:* sKerningAmount Two-byte signed integer indicating the amount of kerning. Positive numbers specify increased inter-character spacing.
:* sSecondChar Code point for the second character  
;pInstance (PVOID) - input : Pointer to instance data.
:* sKerningAmount Two-byte signed integer indicating the amount of kerning. Positive numbers specify increased inter-character spacing.  
;lFunction (ULONG) - input : High-order WORD=flags;. low-order WORD=NGreGetPairKerningTable.
 
; pInstance (PVOID) - input : Pointer to instance data.  
 
; lFunction (ULONG) - input : High-order WORD=flags;. low-order WORD=NGreGetPairKerningTable.  


== Returns ==
== Returns ==
; rc (LONG) - returns : Return Code.  
;rc (LONG) - returns : Return Code.
 
On completion, the handling routine must return the number of kerning pairs returned in pKernPairs (cPairs), or GPI_ALTERROR if an error occurs.
On completion, the handling routine must return the number of kerning pairs returned in pKernPairs (cPairs), or GPI_ALTERROR if an error occurs.  
 
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_CODEPAGE
* PMERR_INV_COORD_SPACE
* PMERR_INV_HDC
* PMERR_INV_LENGTH_OR_COUNT
* PMERR_INV_SETID
 
Refer to the "Error Explanations" section in the Presentation Manager Programming Reference for further explanation.
 
 
== Sample ==
<pre>
#define INCL_GRE_DEVMISC1
#include <os2.h>
 
HDC          hdc;        /*  Device context handle. */
LONG          cKernPairs;  /*  Number of kerning pairs requested by the application. */
PKERNPAIRS    pKernPairs;  /*  Pointer to kerning pair records. */
PVOID        pInstance;  /*  Pointer to instance data. */
ULONG        lFunction;  /*  High-order WORD=flags;. low-order WORD=NGreGetPairKerningTable. */
LONG          rc;          /*  Return Code. */


rc = GreGetPairKerningTable(hdc, cKernPairs,
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:
      pKernPairs, pInstance, lFunction);
* PMERR_COORDINATE_OVERFLOW
</pre>
* PMERR_DEV_FUNC_NOT_INSTALLED
* PMERR_EXCEEDS_MAX_SEG_LENGTH
* PMERR_HDC_BUSY
* PMERR_INSUFFICIENT_MEMORY
* PMERR_INV_CODEPAGE
* PMERR_INV_COORD_SPACE
* PMERR_INV_HDC
* PMERR_INV_LENGTH_OR_COUNT
* PMERR_INV_SETID
Refer to the "Error Explanations" section in the ''Presentation Manager Programming Reference'' for further explanation.


== Remarks ==
== Remarks ==
The handling routine must transform all kerning-pair coordinates from device to world coordinates before sending the data to the calling routine. This can be done by using [[GreConvert]]. If it is unable to do this because the transform matrix is singular, it must log PMERR_COORDINATE_OVERFLOW.  
The handling routine must transform all kerning-pair coordinates from device to world coordinates before sending the data to the calling routine. This can be done by using [[GreConvert]]. If it is unable to do this because the transform matrix is singular, it must log PMERR_COORDINATE_OVERFLOW.


The number of kerning pairs is a field in the FONTMETRICS structure.  
The number of kerning pairs is a field in the [[FONTMETRICS]] structure.


[[Category:Gre]]
[[Category:Gre]]

Latest revision as of 12:33, 20 January 2020

GreGetPairKerningTable stores the kerning pairs of the current font to the buffer addressed by pKernPairs.

This function must be supported by the presentation driver. The call parameters are passed unchanged to the display driver's dispatch table. GreGetPairKerningTable is called from GpiQueryKerningPairs. GreGetPairKerningTable is used to return the kerning data for the currently selected font. This function can be handled by bit-map simulation.

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

Syntax

GreGetPairKerningTable(hdc, cKernPairs, pKernPairs, pInstance, lFunction)

Parameters

hdc (HDC) - input
Device context handle.
cKernPairs (LONG) - input
Number of kerning pairs requested by the application.
pKernPairs (PKERNPAIRS) - input
Pointer to kerning pair records.
KERNINGPAIRS data structure:
  • sFirstChar Code point for the first character
  • sSecondChar Code point for the second character
  • sKerningAmount Two-byte signed integer indicating the amount of kerning. Positive numbers specify increased inter-character spacing.
pInstance (PVOID) - input
Pointer to instance data.
lFunction (ULONG) - input
High-order WORD=flags;. low-order WORD=NGreGetPairKerningTable.

Returns

rc (LONG) - returns
Return Code.

On completion, the handling routine must return the number of kerning pairs returned in pKernPairs (cPairs), or GPI_ALTERROR if an error occurs.

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_CODEPAGE
  • PMERR_INV_COORD_SPACE
  • PMERR_INV_HDC
  • PMERR_INV_LENGTH_OR_COUNT
  • PMERR_INV_SETID

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

Remarks

The handling routine must transform all kerning-pair coordinates from device to world coordinates before sending the data to the calling routine. This can be done by using GreConvert. If it is unable to do this because the transform matrix is singular, it must log PMERR_COORDINATE_OVERFLOW.

The number of kerning pairs is a field in the FONTMETRICS structure.

Retrieved from "https://www.edm2.com/index.php?title=GreGetPairKerningTable&oldid=69668"