--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-aat-layout-trak-table.hh	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,230 @@
+/*
+ * Copyright © 2018  Ebrahim Byagowi
+ * Copyright © 2018  Google, Inc.
+ *
+ *  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.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_AAT_LAYOUT_TRAK_TABLE_HH
+#define HB_AAT_LAYOUT_TRAK_TABLE_HH
+
+#include "hb-aat-layout-common.hh"
+#include "hb-ot-layout.hh"
+#include "hb-open-type.hh"
+
+/*
+ * trak -- Tracking
+ * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6trak.html
+ */
+#define HB_AAT_TAG_trak HB_TAG('t','r','a','k')
+
+
+namespace AAT {
+
+
+struct TrackTableEntry
+{
+  friend struct TrackData;
+
+  float get_track_value () const { return track.to_float (); }
+
+  int get_value (const void *base, unsigned int index,
+		 unsigned int table_size) const
+  { return (base+valuesZ).as_array (table_size)[index]; }
+
+  public:
+  bool sanitize (hb_sanitize_context_t *c, const void *base,
+		 unsigned int table_size) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (likely (c->check_struct (this) &&
+			  (valuesZ.sanitize (c, base, table_size))));
+  }
+
+  protected:
+  F16DOT16	track;		/* Track value for this record. */
+  NameID	trackNameID;	/* The 'name' table index for this track.
+				 * (a short word or phrase like "loose"
+				 * or "very tight") */
+  NNOffset16To<UnsizedArrayOf<FWORD>>
+		valuesZ;	/* Offset from start of tracking table to
+				 * per-size tracking values for this track. */
+
+  public:
+  DEFINE_SIZE_STATIC (8);
+};
+
+struct TrackData
+{
+  float interpolate_at (unsigned int idx,
+			float target_size,
+			const TrackTableEntry &trackTableEntry,
+			const void *base) const
+  {
+    unsigned int sizes = nSizes;
+    hb_array_t<const F16DOT16> size_table ((base+sizeTable).arrayZ, sizes);
+
+    float s0 = size_table[idx].to_float ();
+    float s1 = size_table[idx + 1].to_float ();
+    float t = unlikely (s0 == s1) ? 0.f : (target_size - s0) / (s1 - s0);
+    return t * trackTableEntry.get_value (base, idx + 1, sizes) +
+	   (1.f - t) * trackTableEntry.get_value (base, idx, sizes);
+  }
+
+  int get_tracking (const void *base, float ptem) const
+  {
+    /*
+     * Choose track.
+     */
+    const TrackTableEntry *trackTableEntry = nullptr;
+    unsigned int count = nTracks;
+    for (unsigned int i = 0; i < count; i++)
+    {
+      /* Note: Seems like the track entries are sorted by values.  But the
+       * spec doesn't explicitly say that.  It just mentions it in the example. */
+
+      /* For now we only seek for track entries with zero tracking value */
+
+      if (trackTable[i].get_track_value () == 0.f)
+      {
+	trackTableEntry = &trackTable[i];
+	break;
+      }
+    }
+    if (!trackTableEntry) return 0.;
+
+    /*
+     * Choose size.
+     */
+    unsigned int sizes = nSizes;
+    if (!sizes) return 0.;
+    if (sizes == 1) return trackTableEntry->get_value (base, 0, sizes);
+
+    hb_array_t<const F16DOT16> size_table ((base+sizeTable).arrayZ, sizes);
+    unsigned int size_index;
+    for (size_index = 0; size_index < sizes - 1; size_index++)
+      if (size_table[size_index].to_float () >= ptem)
+	break;
+
+    return roundf (interpolate_at (size_index ? size_index - 1 : 0, ptem,
+				   *trackTableEntry, base));
+  }
+
+  bool sanitize (hb_sanitize_context_t *c, const void *base) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (likely (c->check_struct (this) &&
+			  sizeTable.sanitize (c, base, nSizes) &&
+			  trackTable.sanitize (c, nTracks, base, nSizes)));
+  }
+
+  protected:
+  HBUINT16	nTracks;	/* Number of separate tracks included in this table. */
+  HBUINT16	nSizes;		/* Number of point sizes included in this table. */
+  NNOffset32To<UnsizedArrayOf<F16DOT16>>
+		sizeTable;	/* Offset from start of the tracking table to
+				 * Array[nSizes] of size values.. */
+  UnsizedArrayOf<TrackTableEntry>
+		trackTable;	/* Array[nTracks] of TrackTableEntry records. */
+
+  public:
+  DEFINE_SIZE_ARRAY (8, trackTable);
+};
+
+struct trak
+{
+  static constexpr hb_tag_t tableTag = HB_AAT_TAG_trak;
+
+  bool has_data () const { return version.to_int (); }
+
+  bool apply (hb_aat_apply_context_t *c) const
+  {
+    TRACE_APPLY (this);
+
+    hb_mask_t trak_mask = c->plan->trak_mask;
+
+    const float ptem = c->font->ptem;
+    if (unlikely (ptem <= 0.f))
+      return_trace (false);
+
+    hb_buffer_t *buffer = c->buffer;
+    if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
+    {
+      const TrackData &trackData = this+horizData;
+      int tracking = trackData.get_tracking (this, ptem);
+      hb_position_t offset_to_add = c->font->em_scalef_x (tracking / 2);
+      hb_position_t advance_to_add = c->font->em_scalef_x (tracking);
+      foreach_grapheme (buffer, start, end)
+      {
+	if (!(buffer->info[start].mask & trak_mask)) continue;
+	buffer->pos[start].x_advance += advance_to_add;
+	buffer->pos[start].x_offset += offset_to_add;
+      }
+    }
+    else
+    {
+      const TrackData &trackData = this+vertData;
+      int tracking = trackData.get_tracking (this, ptem);
+      hb_position_t offset_to_add = c->font->em_scalef_y (tracking / 2);
+      hb_position_t advance_to_add = c->font->em_scalef_y (tracking);
+      foreach_grapheme (buffer, start, end)
+      {
+	if (!(buffer->info[start].mask & trak_mask)) continue;
+	buffer->pos[start].y_advance += advance_to_add;
+	buffer->pos[start].y_offset += offset_to_add;
+      }
+    }
+
+    return_trace (true);
+  }
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+
+    return_trace (likely (c->check_struct (this) &&
+			  version.major == 1 &&
+			  horizData.sanitize (c, this, this) &&
+			  vertData.sanitize (c, this, this)));
+  }
+
+  protected:
+  FixedVersion<>version;	/* Version of the tracking table
+				 * (0x00010000u for version 1.0). */
+  HBUINT16	format;		/* Format of the tracking table (set to 0). */
+  Offset16To<TrackData>
+		horizData;	/* Offset from start of tracking table to TrackData
+				 * for horizontal text (or 0 if none). */
+  Offset16To<TrackData>
+		vertData;	/* Offset from start of tracking table to TrackData
+				 * for vertical text (or 0 if none). */
+  HBUINT16	reserved;	/* Reserved. Set to 0. */
+
+  public:
+  DEFINE_SIZE_STATIC (12);
+};
+
+} /* namespace AAT */
+
+
+#endif /* HB_AAT_LAYOUT_TRAK_TABLE_HH */