harfbuzz/src/hb-old.cc

400 lines
11 KiB
C++
Raw Normal View History

/*
* 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
*/
#include "hb-private.hh"
#include "hb-old-private.hh"
#include "hb-font-private.hh"
#include "hb-buffer-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;
/* TODO Handle UTF-16. Ugh */
u = string[i];
if (rightToLeft)
u = hb_unicode_mirroring (hb_unicode_funcs_get_default (), u);
hb_font_get_glyph (font, 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] = hb_font_get_glyph_h_advance (font, 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)
{
// TODO
}
static HB_Fixed
hb_old_getFontMetric (HB_Font old_font,
HB_FontMetric metric)
{
return 0; // TODO
}
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_user_data_key_t hb_old_data_key;
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 = hb_face_reference_table (face, (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;
}
static HB_Face
_hb_old_face_get (hb_face_t *face)
{
HB_Face data = (HB_Face) hb_face_get_user_data (face, &hb_old_data_key);
if (likely (data)) return data;
data = HB_NewFace (face, table_func);
if (unlikely (!data)) {
DEBUG_MSG (OLD, face, "HB_NewFace failed");
return NULL;
}
if (unlikely (!hb_face_set_user_data (face, &hb_old_data_key, data,
(hb_destroy_func_t) HB_FreeFace,
false)))
{
HB_FreeFace (data);
data = (HB_Face) hb_face_get_user_data (face, &hb_old_data_key);
if (data)
return data;
else
return NULL;
}
return data;
}
static HB_Font
_hb_old_font_get (hb_font_t *font)
{
HB_Font data = (HB_Font) 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;
if (unlikely (!hb_font_set_user_data (font, &hb_old_data_key, data,
(hb_destroy_func_t) free,
false)))
{
free (data);
data = (HB_Font) hb_font_get_user_data (font, &hb_old_data_key);
if (data)
return data;
else
return NULL;
}
return data;
}
hb_bool_t
_hb_old_shape (hb_font_t *font,
hb_buffer_t *buffer,
const hb_feature_t *features,
unsigned int num_features)
{
if (unlikely (!buffer->len))
return true;
buffer->guess_properties ();
bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
#define FAIL(...) \
HB_STMT_START { \
DEBUG_MSG (OLD, NULL, __VA_ARGS__); \
return false; \
} HB_STMT_END;
HB_Face old_face = _hb_old_face_get (font->face);
if (unlikely (!old_face))
FAIL ("Couldn't get old face");
HB_Font old_font = _hb_old_font_get (font);
if (unlikely (!old_font))
FAIL ("Couldn't get old font");
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);
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)
FAIL ("Buffer resize failed");
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);
}
if (!backward) {
for (unsigned int i = 1; i < num_glyphs; i++)
if (vis_clusters[i] == -1)
vis_clusters[i] = vis_clusters[i - 1];
} else {
for (int i = num_glyphs - 2; i >= 0; i--)
if (vis_clusters[i] == -1)
vis_clusters[i] = vis_clusters[i + 1];
}
#undef utf16_index
buffer->ensure (num_glyphs);
if (buffer->in_error)
FAIL ("Buffer in error");
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;
}