harfbuzz/src/hb-ot-metrics.cc

/*
 * Copyright © 2018  Ebrahim Byagowi
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 */

#include "hb.hh"

#ifndef HB_NO_METRICS

#include "hb-ot-metrics.hh"
#include "hb-ot-var-mvar-table.hh"
#include "hb-ot-face.hh"


/**
 * hb_ot_metrics_get_position:
 * @font: a #hb_font_t object.
 * @metrics_tag: tag of metrics value you like to fetch.
 * @position: (out) (optional): result of metrics value from the font.
 *
 * It fetches metrics value corresponding to a given tag from a font.
 * 
 * Returns: Whether found the requested metrics in the font.
 * Since: REPLACEME
 **/
hb_bool_t
hb_ot_metrics_get_position (hb_font_t       *font,
			    hb_ot_metrics_t  metrics_tag,
			    hb_position_t   *position     /* OUT.  May be NULL. */)
{
  switch (metrics_tag)
  {
  case HB_OT_METRICS_HORIZONTAL_ASCENDER:
  case HB_OT_METRICS_HORIZONTAL_DESCENDER:
  case HB_OT_METRICS_HORIZONTAL_LINE_GAP:
  case HB_OT_METRICS_HORIZONTAL_CLIPPING_ASCENT:
  case HB_OT_METRICS_HORIZONTAL_CLIPPING_DESCENT:
  case HB_OT_METRICS_HORIZONTAL_CARET_RISE:
  case HB_OT_METRICS_VERTICAL_CARET_RUN:
  case HB_OT_METRICS_VERTICAL_CARET_OFFSET:
  case HB_OT_METRICS_X_HEIGHT:
  case HB_OT_METRICS_CAP_HEIGHT:
  case HB_OT_METRICS_SUBSCRIPT_EM_Y_SIZE:
  case HB_OT_METRICS_SUBSCRIPT_EM_Y_OFFSET:
  case HB_OT_METRICS_SUPERSCRIPT_EM_Y_SIZE:
  case HB_OT_METRICS_SUPERSCRIPT_EM_Y_OFFSET:
  case HB_OT_METRICS_STRIKEOUT_SIZE:
  case HB_OT_METRICS_STRIKEOUT_OFFSET:
  case HB_OT_METRICS_UNDERLINE_SIZE:
  case HB_OT_METRICS_UNDERLINE_OFFSET: {
    float value;
    bool result = hb_ot_metrics_get_position_internal (font->face, metrics_tag, &value);
    if (result && position) *position = font->em_scalef_y (value);
    return result;
  }
  case HB_OT_METRICS_VERTICAL_ASCENDER:
  case HB_OT_METRICS_VERTICAL_DESCENDER:
  case HB_OT_METRICS_VERTICAL_LINE_GAP:
  case HB_OT_METRICS_HORIZONTAL_CARET_RUN:
  case HB_OT_METRICS_HORIZONTAL_CARET_OFFSET:
  case HB_OT_METRICS_VERTICAL_CARET_RISE:
  case HB_OT_METRICS_SUBSCRIPT_EM_X_SIZE:
  case HB_OT_METRICS_SUBSCRIPT_EM_X_OFFSET:
  case HB_OT_METRICS_SUPERSCRIPT_EM_X_SIZE:
  case HB_OT_METRICS_SUPERSCRIPT_EM_X_OFFSET: {
    float value;
    bool result = hb_ot_metrics_get_position_internal (font->face, metrics_tag, &value);
    if (result && position) *position = font->em_scalef_x (value);
    return result;
  }
  default:
    return false;
  }
}

#ifndef HB_NO_VAR
/**
 * hb_ot_metrics_get_variation:
 * @face:
 * @metrics_tag:
 *
 * Returns:
 *
 * Since: REPLACEME
 **/
float
hb_ot_metrics_get_variation (hb_face_t *face, hb_ot_metrics_t metrics_tag)
{
  return face->table.MVAR->get_var (metrics_tag, nullptr, 0);
}

/**
 * hb_ot_metrics_get_x_variation:
 * @font:
 * @metrics_tag:
 *
 * Returns:
 *
 * Since: REPLACEME
 **/
hb_position_t
hb_ot_metrics_get_x_variation (hb_font_t *font, hb_ot_metrics_t metrics_tag)
{
  return font->em_scalef_x (hb_ot_metrics_get_variation (font->face, metrics_tag));
}

/**
 * hb_ot_metrics_get_y_variation:
 * @font:
 * @metrics_tag:
 *
 * Returns:
 *
 * Since: REPLACEME
 **/
hb_position_t
hb_ot_metrics_get_y_variation (hb_font_t *font, hb_ot_metrics_t metrics_tag)
{
  return font->em_scalef_y (hb_ot_metrics_get_variation (font->face, metrics_tag));
}
#endif

#endif