harfbuzz-ng roll

third_party/harfbuzz-ng/src/hb-old.cc

+/*
+ * Copyright © 2012  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
+ */
+
+#define HB_SHAPER old
+#define hb_old_shaper_face_data_t HB_FaceRec_
+#define hb_old_shaper_font_data_t HB_Font_
+#include "hb-shaper-impl-private.hh"
+
+#include <harfbuzz.h>
+
+
+#ifndef HB_DEBUG_OLD
+#define HB_DEBUG_OLD (HB_DEBUG+0)
+#endif
+
+
+static HB_Script
+hb_old_script_from_script (hb_script_t script)
+{
+  switch ((hb_tag_t) script)
+  {
+    default:
+    case HB_SCRIPT_COMMON:              return HB_Script_Common;
+    case HB_SCRIPT_GREEK:               return HB_Script_Greek;
+    case HB_SCRIPT_CYRILLIC:            return HB_Script_Cyrillic;
+    case HB_SCRIPT_ARMENIAN:            return HB_Script_Armenian;
+    case HB_SCRIPT_HEBREW:              return HB_Script_Hebrew;
+    case HB_SCRIPT_ARABIC:              return HB_Script_Arabic;
+    case HB_SCRIPT_SYRIAC:              return HB_Script_Syriac;
+    case HB_SCRIPT_THAANA:              return HB_Script_Thaana;
+    case HB_SCRIPT_DEVANAGARI:          return HB_Script_Devanagari;
+    case HB_SCRIPT_BENGALI:             return HB_Script_Bengali;
+    case HB_SCRIPT_GURMUKHI:            return HB_Script_Gurmukhi;
+    case HB_SCRIPT_GUJARATI:            return HB_Script_Gujarati;
+    case HB_SCRIPT_ORIYA:               return HB_Script_Oriya;
+    case HB_SCRIPT_TAMIL:               return HB_Script_Tamil;
+    case HB_SCRIPT_TELUGU:              return HB_Script_Telugu;
+    case HB_SCRIPT_KANNADA:             return HB_Script_Kannada;
+    case HB_SCRIPT_MALAYALAM:           return HB_Script_Malayalam;
+    case HB_SCRIPT_SINHALA:             return HB_Script_Sinhala;
+    case HB_SCRIPT_THAI:                return HB_Script_Thai;
+    case HB_SCRIPT_LAO:                 return HB_Script_Lao;
+    case HB_SCRIPT_TIBETAN:             return HB_Script_Tibetan;
+    case HB_SCRIPT_MYANMAR:             return HB_Script_Myanmar;
+    case HB_SCRIPT_GEORGIAN:            return HB_Script_Georgian;
+    case HB_SCRIPT_HANGUL:              return HB_Script_Hangul;
+    case HB_SCRIPT_OGHAM:               return HB_Script_Ogham;
+    case HB_SCRIPT_RUNIC:               return HB_Script_Runic;
+    case HB_SCRIPT_KHMER:               return HB_Script_Khmer;
+    case HB_SCRIPT_NKO:                 return HB_Script_Nko;
+    case HB_SCRIPT_INHERITED:           return HB_Script_Inherited;
+  }
+}
+
+
+static HB_Bool
+hb_old_convertStringToGlyphIndices (HB_Font old_font,
+                                    const HB_UChar16 *string,
+                                    hb_uint32 length,
+                                    HB_Glyph *glyphs,
+                                    hb_uint32 *numGlyphs,
+                                    HB_Bool rightToLeft)
+{
+  hb_font_t *font = (hb_font_t *) old_font->userData;
+
+  for (unsigned int i = 0; i < length; i++)
+  {
+    hb_codepoint_t u;
+
+    /* XXX Handle UTF-16.  Ugh */
+    u = string[i];
+
+    if (rightToLeft)
+      u = hb_unicode_funcs_get_default ()->mirroring (u);
+
+    font->get_glyph (u, 0, &u); /* TODO Variation selectors */
+
+    glyphs[i] = u;
+  }
+  *numGlyphs = length; // XXX
+
+  return true;
+}
+
+static void
+hb_old_getGlyphAdvances (HB_Font old_font,
+                         const HB_Glyph *glyphs,
+                         hb_uint32 numGlyphs,
+                         HB_Fixed *advances,
+                         int flags /*HB_ShaperFlag*/)
+{
+  hb_font_t *font = (hb_font_t *) old_font->userData;
+
+  for (unsigned int i = 0; i < numGlyphs; i++)
+    advances[i] = font->get_glyph_h_advance (glyphs[i]);
+}
+
+static HB_Bool
+hb_old_canRender (HB_Font old_font,
+                  const HB_UChar16 *string,
+                  hb_uint32 length)
+{
+  return true; // TODO
+}
+
+static HB_Error
+hb_old_getPointInOutline (HB_Font old_font,
+                          HB_Glyph glyph,
+                          int flags /*HB_ShaperFlag*/,
+                          hb_uint32 point,
+                          HB_Fixed *xpos,
+                          HB_Fixed *ypos,
+                          hb_uint32 *nPoints)
+{
+  return HB_Err_Ok; // TODO
+}
+
+static void
+hb_old_getGlyphMetrics (HB_Font old_font,
+                        HB_Glyph glyph,
+                        HB_GlyphMetrics *metrics)
+{
+  hb_font_t *font = (hb_font_t *) old_font->userData;
+
+  hb_glyph_extents_t extents;
+
+  font->get_glyph_extents (glyph, &extents);
+
+  metrics->x       = extents.x_bearing;
+  metrics->y       = extents.y_bearing;
+  metrics->width   = extents.width;
+  metrics->height  = extents.height;
+  metrics->xOffset = font->get_glyph_h_advance (glyph);
+  metrics->yOffset = 0;
+}
+
+static HB_Fixed
+hb_old_getFontMetric (HB_Font old_font,
+                      HB_FontMetric metric)
+{
+  hb_font_t *font = (hb_font_t *) old_font->userData;
+
+  switch (metric)
+  {
+    case HB_FontAscent:
+       return font->y_scale; /* XXX We don't have ascent data yet. */
+
+    default:
+      return 0;
+  }
+}
+
+static const HB_FontClass hb_old_font_class = {
+  hb_old_convertStringToGlyphIndices,
+  hb_old_getGlyphAdvances,
+  hb_old_canRender,
+  hb_old_getPointInOutline,
+  hb_old_getGlyphMetrics,
+  hb_old_getFontMetric
+};
+
+
+
+static HB_Error
+table_func (void *font, HB_Tag tag, HB_Byte *buffer, HB_UInt *length)
+{
+  hb_face_t *face = (hb_face_t *) font;
+  hb_blob_t *blob = face->reference_table ((hb_tag_t) tag);
+  unsigned int capacity = *length;
+  *length = hb_blob_get_length (blob);
+  memcpy (buffer, hb_blob_get_data (blob, NULL), MIN (capacity, *length));
+  hb_blob_destroy (blob);
+ return HB_Err_Ok;
+}
+
+
+/*
+ * shaper face data
+ */
+
+hb_old_shaper_face_data_t *
+_hb_old_shaper_face_data_create (hb_face_t *face)
+{
+  return HB_NewFace (face, table_func);
+}
+
+void
+_hb_old_shaper_face_data_destroy (hb_old_shaper_face_data_t *data)
+{
+  HB_FreeFace (data);
+}
+
+
+/*
+ * shaper font data
+ */
+
+hb_old_shaper_font_data_t *
+_hb_old_shaper_font_data_create (hb_font_t *font)
+{
+  HB_FontRec *data = (HB_FontRec *) calloc (1, sizeof (HB_FontRec));
+  if (unlikely (!data)) {
+    DEBUG_MSG (OLD, font, "malloc()ing HB_Font failed");
+    return NULL;
+  }
+
+  data->klass = &hb_old_font_class;
+  data->x_ppem = font->x_ppem;
+  data->y_ppem = font->y_ppem;
+  data->x_scale = font->x_scale; // XXX
+  data->y_scale = font->y_scale; // XXX
+  data->userData = font;
+
+  return data;
+}
+
+void
+_hb_old_shaper_font_data_destroy (hb_old_shaper_font_data_t *data)
+{
+  free (data);
+}
+
+
+/*
+ * shaper shape_plan data
+ */
+
+struct hb_old_shaper_shape_plan_data_t {};
+
+hb_old_shaper_shape_plan_data_t *
+_hb_old_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan,
+                                       const hb_feature_t *user_features,
+                                       unsigned int        num_user_features)
+{
+  return (hb_old_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
+}
+
+void
+_hb_old_shaper_shape_plan_data_destroy (hb_old_shaper_shape_plan_data_t *data)
+{
+}
+
+
+/*
+ * shaper
+ */
+
+hb_bool_t
+_hb_old_shape (hb_shape_plan_t    *shape_plan,
+               hb_font_t          *font,
+               hb_buffer_t        *buffer,
+               const hb_feature_t *features,
+               unsigned int        num_features)
+{
+  hb_face_t *face = font->face;
+  HB_Face old_face = HB_SHAPER_DATA_GET (face);
+  HB_Font old_font = HB_SHAPER_DATA_GET (font);
+
+  bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
+
+retry:
+
+  unsigned int scratch_size;
+  char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
+
+#define utf16_index() var1.u32
+  HB_UChar16 *pchars = (HB_UChar16 *) scratch;
+  unsigned int chars_len = 0;
+  for (unsigned int i = 0; i < buffer->len; i++) {
+    hb_codepoint_t c = buffer->info[i].codepoint;
+    buffer->info[i].utf16_index() = chars_len;
+    if (likely (c < 0x10000))
+      pchars[chars_len++] = c;
+    else if (unlikely (c >= 0x110000))
+      pchars[chars_len++] = 0xFFFD;
+    else {
+      pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
+      pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
+    }
+  }
+
+
+#define ALLOCATE_ARRAY(Type, name, len) \
+  name = (Type *) scratch; \
+  scratch += (len) * sizeof ((name)[0]); \
+  scratch_size -= (len) * sizeof ((name)[0]);
+
+
+  HB_ShaperItem item = {0};
+
+  ALLOCATE_ARRAY (const HB_UChar16, item.string, chars_len);
+  ALLOCATE_ARRAY (unsigned short, item.log_clusters, chars_len + 2);
+  item.stringLength = chars_len;
+  item.item.pos = 0;
+  item.item.length = item.stringLength;
+  item.item.script = hb_old_script_from_script (buffer->props.script);
+  item.item.bidiLevel = backward ? 1 : 0;
+
+  item.font = old_font;
+  item.face = old_face;
+  item.shaperFlags = 0;
+
+  item.glyphIndicesPresent = false;
+
+  /* TODO Alignment. */
+  unsigned int num_glyphs = scratch_size / (sizeof (HB_Glyph) +
+                                            sizeof (HB_GlyphAttributes) +
+                                            sizeof (HB_Fixed) +
+                                            sizeof (HB_FixedPoint) +
+                                            sizeof (uint32_t));
+
+  item.num_glyphs = num_glyphs;
+  ALLOCATE_ARRAY (HB_Glyph, item.glyphs, num_glyphs);
+  ALLOCATE_ARRAY (HB_GlyphAttributes, item.attributes, num_glyphs);
+  ALLOCATE_ARRAY (HB_Fixed, item.advances, num_glyphs);
+  ALLOCATE_ARRAY (HB_FixedPoint, item.offsets, num_glyphs);
+  /* Apparently in some cases the offsets array will not be fully assigned to.
+   * Clear it. */
+  memset (item.offsets, 0, num_glyphs * sizeof (item.offsets[0]));
+  uint32_t *vis_clusters;
+  ALLOCATE_ARRAY (uint32_t, vis_clusters, num_glyphs);
+
+#undef ALLOCATE_ARRAY
+
+  if (!HB_ShapeItem (&item))
+  {
+    if (unlikely (item.num_glyphs > num_glyphs))
+    {
+      buffer->ensure (buffer->allocated * 2);
+      if (buffer->in_error)
+        return false;
+      goto retry;
+    }
+    return false;
+  }
+  num_glyphs = item.num_glyphs;
+
+  /* Ok, we've got everything we need, now compose output buffer,
+   * very, *very*, carefully! */
+
+  /* Calculate visual-clusters.  That's what we ship. */
+  for (unsigned int i = 0; i < num_glyphs; i++)
+    vis_clusters[i] = -1;
+  for (unsigned int i = 0; i < buffer->len; i++) {
+    uint32_t *p = &vis_clusters[item.log_clusters[buffer->info[i].utf16_index()]];
+    *p = MIN (*p, buffer->info[i].cluster);
+  }
+  for (unsigned int i = 1; i < num_glyphs; i++)
+    if (vis_clusters[i] == -1)
+      vis_clusters[i] = vis_clusters[i - 1];
+
+#undef utf16_index
+
+  buffer->ensure (num_glyphs);
+  if (buffer->in_error)
+    return false;
+
+
+  buffer->len = num_glyphs;
+  hb_glyph_info_t *info = buffer->info;
+  for (unsigned int i = 0; i < num_glyphs; i++)
+  {
+    info[i].codepoint = item.glyphs[i];
+    info[i].cluster = vis_clusters[i];
+
+    info[i].mask = item.advances[i];
+    info[i].var1.u32 = item.offsets[i].x;
+    info[i].var2.u32 = item.offsets[i].y;
+  }
+
+  buffer->clear_positions ();
+
+  for (unsigned int i = 0; i < num_glyphs; ++i) {
+    hb_glyph_info_t *info = &buffer->info[i];
+    hb_glyph_position_t *pos = &buffer->pos[i];
+
+    /* TODO vertical */
+    pos->x_advance = info->mask;
+    pos->x_offset = info->var1.u32;
+    pos->y_offset = info->var2.u32;
+  }
+
+  if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
+    buffer->reverse ();
+
+  return true;
+}