godot/thirdparty/freetype/src/autofit/afcjk.c

/****************************************************************************
 *
 * afcjk.c
 *
 *   Auto-fitter hinting routines for CJK writing system (body).
 *
 * Copyright (C) 2006-2023 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.
 *
 */

  /*
   * The algorithm is based on akito's autohint patch, archived at
   *
   * https://web.archive.org/web/20051219160454/http://www.kde.gr.jp:80/~akito/patch/freetype2/2.1.7/
   *
   */

#include <freetype/ftadvanc.h>
#include <freetype/internal/ftdebug.h>

#include "afglobal.h"
#include "aflatin.h"
#include "afcjk.h"


#ifdef AF_CONFIG_OPTION_CJK

#undef AF_CONFIG_OPTION_CJK_BLUE_HANI_VERT

#include "aferrors.h"


  /**************************************************************************
   *
   * The macro FT_COMPONENT is used in trace mode.  It is an implicit
   * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
   * messages during execution.
   */
#undef  FT_COMPONENT
#define FT_COMPONENT


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****              C J K   G L O B A L   M E T R I C S              *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  /* Basically the Latin version with AF_CJKMetrics */
  /* to replace AF_LatinMetrics.                    */

  FT_LOCAL_DEF( void )
  af_cjk_metrics_init_widths( AF_CJKMetrics  metrics,
                              FT_Face        face )
  {}


  /* Find all blue zones. */

  static void
  af_cjk_metrics_init_blues( AF_CJKMetrics  metrics,
                             FT_Face        face )
  {}


  /* Basically the Latin version with type AF_CJKMetrics for metrics. */

  FT_LOCAL_DEF( void )
  af_cjk_metrics_check_digits( AF_CJKMetrics  metrics,
                               FT_Face        face )
  {}


  /* Initialize global metrics. */

  FT_LOCAL_DEF( FT_Error )
  af_cjk_metrics_init( AF_StyleMetrics  metrics_,  /* AF_CJKMetrics */
                       FT_Face          face )
  {}


  /* Adjust scaling value, then scale and shift widths   */
  /* and blue zones (if applicable) for given dimension. */

  static void
  af_cjk_metrics_scale_dim( AF_CJKMetrics  metrics,
                            AF_Scaler      scaler,
                            AF_Dimension   dim )
  {}


  /* Scale global values in both directions. */

  FT_LOCAL_DEF( void )
  af_cjk_metrics_scale( AF_StyleMetrics  metrics_,   /* AF_CJKMetrics */
                        AF_Scaler        scaler )
  {}


  /* Extract standard_width from writing system/script specific */
  /* metrics class.                                             */

  FT_CALLBACK_DEF( void )
  af_cjk_get_standard_widths( AF_StyleMetrics  metrics_,  /* AF_CJKMetrics */
                              FT_Pos*          stdHW,
                              FT_Pos*          stdVW )
  {}


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****              C J K   G L Y P H   A N A L Y S I S              *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  /* Walk over all contours and compute its segments. */

  static FT_Error
  af_cjk_hints_compute_segments( AF_GlyphHints  hints,
                                 AF_Dimension   dim )
  {}


  static void
  af_cjk_hints_link_segments( AF_GlyphHints  hints,
                              AF_Dimension   dim )
  {}


  static FT_Error
  af_cjk_hints_compute_edges( AF_GlyphHints  hints,
                              AF_Dimension   dim )
  {}


  /* Detect segments and edges for given dimension. */

  static FT_Error
  af_cjk_hints_detect_features( AF_GlyphHints  hints,
                                AF_Dimension   dim )
  {}


  /* Compute all edges which lie within blue zones. */

  static void
  af_cjk_hints_compute_blue_edges( AF_GlyphHints  hints,
                                   AF_CJKMetrics  metrics,
                                   AF_Dimension   dim )
  {}


  /* Initalize hinting engine. */

  FT_LOCAL_DEF( FT_Error )
  af_cjk_hints_init( AF_GlyphHints    hints,
                     AF_StyleMetrics  metrics_ )   /* AF_CJKMetrics */
  {}


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****          C J K   G L Y P H   G R I D - F I T T I N G          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /* Snap a given width in scaled coordinates to one of the */
  /* current standard widths.                               */

  static FT_Pos
  af_cjk_snap_width( AF_Width  widths,
                     FT_UInt   count,
                     FT_Pos    width )
  {}


  /* Compute the snapped width of a given stem.                          */
  /* There is a lot of voodoo in this function; changing the hard-coded  */
  /* parameters influence the whole hinting process.                     */

  static FT_Pos
  af_cjk_compute_stem_width( AF_GlyphHints  hints,
                             AF_Dimension   dim,
                             FT_Pos         width,
                             FT_UInt        base_flags,
                             FT_UInt        stem_flags )
  {}


  /* Align one stem edge relative to the previous stem edge. */

  static void
  af_cjk_align_linked_edge( AF_GlyphHints  hints,
                            AF_Dimension   dim,
                            AF_Edge        base_edge,
                            AF_Edge        stem_edge )
  {}


  /* Shift the coordinates of the `serif' edge by the same amount */
  /* as the corresponding `base' edge has been moved already.     */

  static void
  af_cjk_align_serif_edge( AF_GlyphHints  hints,
                           AF_Edge        base,
                           AF_Edge        serif )
  {}


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****                    E D G E   H I N T I N G                      ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


#define AF_LIGHT_MODE_MAX_HORZ_GAP
#define AF_LIGHT_MODE_MAX_VERT_GAP
#define AF_LIGHT_MODE_MAX_DELTA_ABS


  static FT_Pos
  af_hint_normal_stem( AF_GlyphHints  hints,
                       AF_Edge        edge,
                       AF_Edge        edge2,
                       FT_Pos         anchor,
                       AF_Dimension   dim )
  {}


  /* The main grid-fitting routine. */

  static void
  af_cjk_hint_edges( AF_GlyphHints  hints,
                     AF_Dimension   dim )
  {}


  static void
  af_cjk_align_edge_points( AF_GlyphHints  hints,
                            AF_Dimension   dim )
  {}


  /* Apply the complete hinting algorithm to a CJK glyph. */

  FT_LOCAL_DEF( FT_Error )
  af_cjk_hints_apply( FT_UInt          glyph_index,
                      AF_GlyphHints    hints,
                      FT_Outline*      outline,
                      AF_StyleMetrics  metrics_ )   /* AF_CJKMetrics */
  {}


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                C J K   S C R I P T   C L A S S                *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  AF_DEFINE_WRITING_SYSTEM_CLASS(
    af_cjk_writing_system_class,

    AF_WRITING_SYSTEM_CJK,

    sizeof ( AF_CJKMetricsRec ),

    (AF_WritingSystem_InitMetricsFunc) af_cjk_metrics_init,        /* style_metrics_init    */
    (AF_WritingSystem_ScaleMetricsFunc)af_cjk_metrics_scale,       /* style_metrics_scale   */
    (AF_WritingSystem_DoneMetricsFunc) NULL,                       /* style_metrics_done    */
    (AF_WritingSystem_GetStdWidthsFunc)af_cjk_get_standard_widths, /* style_metrics_getstdw */

    (AF_WritingSystem_InitHintsFunc)   af_cjk_hints_init,          /* style_hints_init      */
    (AF_WritingSystem_ApplyHintsFunc)  af_cjk_hints_apply          /* style_hints_apply     */
  )


#else /* !AF_CONFIG_OPTION_CJK */


  AF_DEFINE_WRITING_SYSTEM_CLASS(
    af_cjk_writing_system_class,

    AF_WRITING_SYSTEM_CJK,

    sizeof ( AF_CJKMetricsRec ),

    (AF_WritingSystem_InitMetricsFunc) NULL, /* style_metrics_init    */
    (AF_WritingSystem_ScaleMetricsFunc)NULL, /* style_metrics_scale   */
    (AF_WritingSystem_DoneMetricsFunc) NULL, /* style_metrics_done    */
    (AF_WritingSystem_GetStdWidthsFunc)NULL, /* style_metrics_getstdw */

    (AF_WritingSystem_InitHintsFunc)   NULL, /* style_hints_init      */
    (AF_WritingSystem_ApplyHintsFunc)  NULL  /* style_hints_apply     */
  )


#endif /* !AF_CONFIG_OPTION_CJK */


/* END */