pshints.h

奇趣公司比较新的qt/emd版本

/***************************************************************************/
/*                                                                         */
/*  pshints.h                                                              */
/*                                                                         */
/*    Interface to Postscript-specific (Type 1 and Type 2) hints           */
/*    recorders (specification only).  These are used to support native    */
/*    T1/T2 hints in the `type1', `cid', and `cff' font drivers.           */
/*                                                                         */
/*  Copyright 2001, 2002, 2003, 2005, 2006, 2007 by                        */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#ifndef __PSHINTS_H__
#define __PSHINTS_H__


#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_TYPE1_TABLES_H


FT_BEGIN_HEADER


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****               INTERNAL REPRESENTATION OF GLOBALS              *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  typedef struct PSH_GlobalsRec_*  PSH_Globals;

  typedef FT_Error
  (*PSH_Globals_NewFunc)( FT_Memory     memory,
                          T1_Private*   private_dict,
                          PSH_Globals*  aglobals );

  typedef FT_Error
  (*PSH_Globals_SetScaleFunc)( PSH_Globals  globals,
                               FT_Fixed     x_scale,
                               FT_Fixed     y_scale,
                               FT_Fixed     x_delta,
                               FT_Fixed     y_delta );

  typedef void
  (*PSH_Globals_DestroyFunc)( PSH_Globals  globals );


  typedef struct  PSH_Globals_FuncsRec_
  {
    PSH_Globals_NewFunc       create;
    PSH_Globals_SetScaleFunc  set_scale;
    PSH_Globals_DestroyFunc   destroy;

  } PSH_Globals_FuncsRec, *PSH_Globals_Funcs;


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                  PUBLIC TYPE 1 HINTS RECORDER                 *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /*************************************************************************
   *
   * @type:
   *   T1_Hints
   *
   * @description:
   *   This is a handle to an opaque structure used to record glyph hints
   *   from a Type 1 character glyph character string.
   *
   *   The methods used to operate on this object are defined by the
   *   @T1_Hints_FuncsRec structure.  Recording glyph hints is normally
   *   achieved through the following scheme:
   *
   *   - Open a new hint recording session by calling the `open' method.
   *     This rewinds the recorder and prepare it for new input.
   *
   *   - For each hint found in the glyph charstring, call the corresponding
   *     method (`stem', `stem3', or `reset').  Note that these functions do
   *     not return an error code.
   *
   *   - Close the recording session by calling the `close' method.  It
   *     returns an error code if the hints were invalid or something
   *     strange happened (e.g., memory shortage).
   *
   *   The hints accumulated in the object can later be used by the
   *   PostScript hinter.
   *
   */
  typedef struct T1_HintsRec_*  T1_Hints;


  /*************************************************************************
   *
   * @type:
   *   T1_Hints_Funcs
   *
   * @description:
   *   A pointer to the @T1_Hints_FuncsRec structure that defines the API of
   *   a given @T1_Hints object.
   *
   */
  typedef const struct T1_Hints_FuncsRec_*  T1_Hints_Funcs;


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_OpenFunc
   *
   * @description:
   *   A method of the @T1_Hints class used to prepare it for a new Type 1
   *   hints recording session.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   * @note:
   *   You should always call the @T1_Hints_CloseFunc method in order to
   *   close an opened recording session.
   *
   */
  typedef void
  (*T1_Hints_OpenFunc)( T1_Hints  hints );


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_SetStemFunc
   *
   * @description:
   *   A method of the @T1_Hints class used to record a new horizontal or
   *   vertical stem.  This corresponds to the Type 1 `hstem' and `vstem'
   *   operators.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   *   dimension ::
   *     0 for horizontal stems (hstem), 1 for vertical ones (vstem).
   *
   *   coords ::
   *     Array of 2 integers, used as (position,length) stem descriptor.
   *
   * @note:
   *   Use vertical coordinates (y) for horizontal stems (dim=0).  Use
   *   horizontal coordinates (x) for vertical stems (dim=1).
   *
   *   `coords[0]' is the absolute stem position (lowest coordinate);
   *   `coords[1]' is the length.
   *
   *   The length can be negative, in which case it must be either -20 or
   *   -21.  It is interpreted as a `ghost' stem, according to the Type 1
   *   specification.
   *
   *   If the length is -21 (corresponding to a bottom ghost stem), then
   *   the real stem position is `coords[0]+coords[1]'.
   *
   */
  typedef void
  (*T1_Hints_SetStemFunc)( T1_Hints  hints,
                           FT_UInt   dimension,
                           FT_Long*  coords );


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_SetStem3Func
   *
   * @description:
   *   A method of the @T1_Hints class used to record three
   *   counter-controlled horizontal or vertical stems at once.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   *   dimension ::
   *     0 for horizontal stems, 1 for vertical ones.
   *
   *   coords ::
   *     An array of 6 integers, holding 3 (position,length) pairs for the
   *     counter-controlled stems.
   *
   * @note:
   *   Use vertical coordinates (y) for horizontal stems (dim=0).  Use
   *   horizontal coordinates (x) for vertical stems (dim=1).
   *
   *   The lengths cannot be negative (ghost stems are never
   *   counter-controlled).
   *
   */
  typedef void
  (*T1_Hints_SetStem3Func)( T1_Hints  hints,
                            FT_UInt   dimension,
                            FT_Long*  coords );


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_ResetFunc
   *
   * @description:
   *   A method of the @T1_Hints class used to reset the stems hints in a
   *   recording session.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   *   end_point ::
   *     The index of the last point in the input glyph in which the
   *     previously defined hints apply.
   *
   */
  typedef void
  (*T1_Hints_ResetFunc)( T1_Hints  hints,
                         FT_UInt   end_point );


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_CloseFunc
   *
   * @description:
   *   A method of the @T1_Hints class used to close a hint recording
   *   session.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   *   end_point ::
   *     The index of the last point in the input glyph.
   *
   * @return:
   *   FreeType error code.  0 means success.
   *
   * @note:
   *   The error code is set to indicate that an error occurred during the
   *   recording session.
   *
   */
  typedef FT_Error
  (*T1_Hints_CloseFunc)( T1_Hints  hints,
                         FT_UInt   end_point );


  /*************************************************************************
   *
   * @functype:
   *   T1_Hints_ApplyFunc
   *
   * @description:
   *   A method of the @T1_Hints class used to apply hints to the
   *   corresponding glyph outline.  Must be called once all hints have been
   *   recorded.
   *
   * @input:
   *   hints ::
   *     A handle to the Type 1 hints recorder.
   *
   *   outline ::
   *     A pointer to the target outline descriptor.
   *
   *   globals ::
   *     The hinter globals for this font.
   *
   *   hint_mode ::
   *     Hinting information.
   *
   * @return:
   *   FreeType error code.  0 means success.
   *
   * @note:
   *   On input, all points within the outline are in font coordinates. On
   *   output, they are in 1/64th of pixels.
   *
   *   The scaling transformation is taken from the `globals' object which
   *   must correspond to the same font as the glyph.
   *
   */
  typedef FT_Error
  (*T1_Hints_ApplyFunc)( T1_Hints        hints,
                         FT_Outline*     outline,
                         PSH_Globals     globals,
                         FT_Render_Mode  hint_mode );


  /*************************************************************************
   *
   * @struct:
   *   T1_Hints_FuncsRec
   *
   * @description:
   *   The structure used to provide the API to @T1_Hints objects.
   *
   * @fields:
   *   hints ::
   *     A handle to the T1 Hints recorder.
   *
   *   open ::
   *     The function to open a recording session.
   *
   *   close ::
   *     The function to close a recording session.
   *
   *   stem ::
   *     The function to set a simple stem.
   *
   *   stem3 ::
   *     The function to set counter-controlled stems.
   *
   *   reset ::
   *     The function to reset stem hints.
   *
   *   apply ::
   *     The function to apply the hints to the corresponding glyph outline.
   *
   */
  typedef struct  T1_Hints_FuncsRec_
  {
    T1_Hints               hints;
    T1_Hints_OpenFunc      open;