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diff --git a/src/3rdparty/freetype/src/autofit/hbshim.c b/src/3rdparty/freetype/src/autofit/hbshim.c
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+/***************************************************************************/
+/* */
+/* hbshim.c */
+/* */
+/* HarfBuzz interface for accessing OpenType features (body). */
+/* */
+/* Copyright 2013, 2014 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. */
+/* */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include "afglobal.h"
+#include "aftypes.h"
+#include "hbshim.h"
+
+#ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
+
+
+ /*************************************************************************/
+ /* */
+ /* 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 trace_afharfbuzz
+
+
+ /*
+ * We use `sets' (in the HarfBuzz sense, which comes quite near to the
+ * usual mathematical meaning) to manage both lookups and glyph indices.
+ *
+ * 1. For each coverage, collect lookup IDs in a set. Note that an
+ * auto-hinter `coverage' is represented by one `feature', and a
+ * feature consists of an arbitrary number of (font specific) `lookup's
+ * that actually do the mapping job. Please check the OpenType
+ * specification for more details on features and lookups.
+ *
+ * 2. Create glyph ID sets from the corresponding lookup sets.
+ *
+ * 3. The glyph set corresponding to AF_COVERAGE_DEFAULT is computed
+ * with all lookups specific to the OpenType script activated. It
+ * relies on the order of AF_DEFINE_STYLE_CLASS entries so that
+ * special coverages (like `oldstyle figures') don't get overwritten.
+ *
+ */
+
+
+ /* load coverage tags */
+#undef COVERAGE
+#define COVERAGE( name, NAME, description, \
+ tag1, tag2, tag3, tag4 ) \
+ static const hb_tag_t name ## _coverage[] = \
+ { \
+ HB_TAG( tag1, tag2, tag3, tag4 ), \
+ HB_TAG_NONE \
+ };
+
+
+#include "afcover.h"
+
+
+ /* define mapping between coverage tags and AF_Coverage */
+#undef COVERAGE
+#define COVERAGE( name, NAME, description, \
+ tag1, tag2, tag3, tag4 ) \
+ name ## _coverage,
+
+
+ static const hb_tag_t* coverages[] =
+ {
+#include "afcover.h"
+
+ NULL /* AF_COVERAGE_DEFAULT */
+ };
+
+
+ /* load HarfBuzz script tags */
+#undef SCRIPT
+#define SCRIPT( s, S, d, h, sc1, sc2, sc3 ) h,
+
+
+ static const hb_script_t scripts[] =
+ {
+#include "afscript.h"
+ };
+
+
+ FT_Error
+ af_get_coverage( AF_FaceGlobals globals,
+ AF_StyleClass style_class,
+ FT_Byte* gstyles )
+ {
+ hb_face_t* face;
+
+ hb_set_t* gsub_lookups; /* GSUB lookups for a given script */
+ hb_set_t* gsub_glyphs; /* glyphs covered by GSUB lookups */
+ hb_set_t* gpos_lookups; /* GPOS lookups for a given script */
+ hb_set_t* gpos_glyphs; /* glyphs covered by GPOS lookups */
+
+ hb_script_t script;
+ const hb_tag_t* coverage_tags;
+ hb_tag_t script_tags[] = { HB_TAG_NONE,
+ HB_TAG_NONE,
+ HB_TAG_NONE,
+ HB_TAG_NONE };
+
+ hb_codepoint_t idx;
+#ifdef FT_DEBUG_LEVEL_TRACE
+ int count;
+#endif
+
+
+ if ( !globals || !style_class || !gstyles )
+ return FT_THROW( Invalid_Argument );
+
+ face = hb_font_get_face( globals->hb_font );
+
+ gsub_lookups = hb_set_create();
+ gsub_glyphs = hb_set_create();
+ gpos_lookups = hb_set_create();
+ gpos_glyphs = hb_set_create();
+
+ coverage_tags = coverages[style_class->coverage];
+ script = scripts[style_class->script];
+
+ /* Convert a HarfBuzz script tag into the corresponding OpenType */
+ /* tag or tags -- some Indic scripts like Devanagari have an old */
+ /* and a new set of features. */
+ hb_ot_tags_from_script( script,
+ &script_tags[0],
+ &script_tags[1] );
+
+ /* `hb_ot_tags_from_script' usually returns HB_OT_TAG_DEFAULT_SCRIPT */
+ /* as the second tag. We change that to HB_TAG_NONE except for the */
+ /* default script. */
+ if ( style_class->script == globals->module->default_script &&
+ style_class->coverage == AF_COVERAGE_DEFAULT )
+ {
+ if ( script_tags[0] == HB_TAG_NONE )
+ script_tags[0] = HB_OT_TAG_DEFAULT_SCRIPT;
+ else
+ {
+ if ( script_tags[1] == HB_TAG_NONE )
+ script_tags[1] = HB_OT_TAG_DEFAULT_SCRIPT;
+ else if ( script_tags[1] != HB_OT_TAG_DEFAULT_SCRIPT )
+ script_tags[2] = HB_OT_TAG_DEFAULT_SCRIPT;
+ }
+ }
+ else
+ {
+ if ( script_tags[1] == HB_OT_TAG_DEFAULT_SCRIPT )
+ script_tags[1] = HB_TAG_NONE;
+ }
+
+ hb_ot_layout_collect_lookups( face,
+ HB_OT_TAG_GSUB,
+ script_tags,
+ NULL,
+ coverage_tags,
+ gsub_lookups );
+
+ if ( hb_set_is_empty( gsub_lookups ) )
+ goto Exit; /* nothing to do */
+
+ hb_ot_layout_collect_lookups( face,
+ HB_OT_TAG_GPOS,
+ script_tags,
+ NULL,
+ coverage_tags,
+ gpos_lookups );
+
+ FT_TRACE4(( "GSUB lookups (style `%s'):\n"
+ " ",
+ af_style_names[style_class->style] ));
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ count = 0;
+#endif
+
+ for ( idx = -1; hb_set_next( gsub_lookups, &idx ); )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE4(( " %d", idx ));
+ count++;
+#endif
+
+ /* get output coverage of GSUB feature */
+ hb_ot_layout_lookup_collect_glyphs( face,
+ HB_OT_TAG_GSUB,
+ idx,
+ NULL,
+ NULL,
+ NULL,
+ gsub_glyphs );
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !count )
+ FT_TRACE4(( " (none)" ));
+ FT_TRACE4(( "\n\n" ));
+#endif
+
+ FT_TRACE4(( "GPOS lookups (style `%s'):\n"
+ " ",
+ af_style_names[style_class->style] ));
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ count = 0;
+#endif
+
+ for ( idx = -1; hb_set_next( gpos_lookups, &idx ); )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE4(( " %d", idx ));
+ count++;
+#endif
+
+ /* get input coverage of GPOS feature */
+ hb_ot_layout_lookup_collect_glyphs( face,
+ HB_OT_TAG_GPOS,
+ idx,
+ NULL,
+ gpos_glyphs,
+ NULL,
+ NULL );
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !count )
+ FT_TRACE4(( " (none)" ));
+ FT_TRACE4(( "\n\n" ));
+#endif
+
+ /*
+ * We now check whether we can construct blue zones, using glyphs
+ * covered by the feature only. In case there is not a single zone
+ * (this is, not a single character is covered), we skip this coverage.
+ *
+ */
+ if ( style_class->coverage != AF_COVERAGE_DEFAULT )
+ {
+ AF_Blue_Stringset bss = style_class->blue_stringset;
+ const AF_Blue_StringRec* bs = &af_blue_stringsets[bss];
+
+ FT_Bool found = 0;
+
+
+ for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ )
+ {
+ const char* p = &af_blue_strings[bs->string];
+
+
+ while ( *p )
+ {
+ hb_codepoint_t ch;
+
+
+ GET_UTF8_CHAR( ch, p );
+
+ for ( idx = -1; hb_set_next( gsub_lookups, &idx ); )
+ {
+ hb_codepoint_t gidx = FT_Get_Char_Index( globals->face, ch );
+
+
+ if ( hb_ot_layout_lookup_would_substitute( face, idx,
+ &gidx, 1, 1 ) )
+ {
+ found = 1;
+ break;
+ }
+ }
+ }
+ }
+
+ if ( !found )
+ {
+ FT_TRACE4(( " no blue characters found; style skipped\n" ));
+ goto Exit;
+ }
+ }
+
+ /*
+ * Various OpenType features might use the same glyphs at different
+ * vertical positions; for example, superscript and subscript glyphs
+ * could be the same. However, the auto-hinter is completely
+ * agnostic of OpenType features after the feature analysis has been
+ * completed: The engine then simply receives a glyph index and returns a
+ * hinted and usually rendered glyph.
+ *
+ * Consider the superscript feature of font `pala.ttf': Some of the
+ * glyphs are `real', this is, they have a zero vertical offset, but
+ * most of them are small caps glyphs shifted up to the superscript
+ * position (this is, the `sups' feature is present in both the GSUB and
+ * GPOS tables). The code for blue zones computation actually uses a
+ * feature's y offset so that the `real' glyphs get correct hints. But
+ * later on it is impossible to decide whether a glyph index belongs to,
+ * say, the small caps or superscript feature.
+ *
+ * For this reason, we don't assign a style to a glyph if the current
+ * feature covers the glyph in both the GSUB and the GPOS tables. This
+ * is quite a broad condition, assuming that
+ *
+ * (a) glyphs that get used in multiple features are present in a
+ * feature without vertical shift,
+ *
+ * and
+ *
+ * (b) a feature's GPOS data really moves the glyph vertically.
+ *
+ * Not fulfilling condition (a) makes a font larger; it would also
+ * reduce the number of glyphs that could be addressed directly without
+ * using OpenType features, so this assumption is rather strong.
+ *
+ * Condition (b) is much weaker, and there might be glyphs which get
+ * missed. However, the OpenType features we are going to handle are
+ * primarily located in GSUB, and HarfBuzz doesn't provide an API to
+ * directly get the necessary information from the GPOS table. A
+ * possible solution might be to directly parse the GPOS table to find
+ * out whether a glyph gets shifted vertically, but this is something I
+ * would like to avoid if not really necessary.
+ *
+ * Note that we don't follow this logic for the default coverage.
+ * Complex scripts like Devanagari have mandatory GPOS features to
+ * position many glyph elements, using mark-to-base or mark-to-ligature
+ * tables; the number of glyphs missed due to condition (b) would be far
+ * too large.
+ *
+ */
+ if ( style_class->coverage != AF_COVERAGE_DEFAULT )
+ hb_set_subtract( gsub_glyphs, gpos_glyphs );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE4(( " glyphs without GPOS data (`*' means already assigned)" ));
+ count = 0;
+#endif
+
+ for ( idx = -1; hb_set_next( gsub_glyphs, &idx ); )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !( count % 10 ) )
+ FT_TRACE4(( "\n"
+ " " ));
+
+ FT_TRACE4(( " %d", idx ));
+ count++;
+#endif
+
+ /* glyph indices returned by `hb_ot_layout_lookup_collect_glyphs' */
+ /* can be arbitrary: some fonts use fake indices for processing */
+ /* internal to GSUB or GPOS, which is fully valid */
+ if ( idx >= (hb_codepoint_t)globals->glyph_count )
+ continue;
+
+ if ( gstyles[idx] == AF_STYLE_UNASSIGNED )
+ gstyles[idx] = (FT_Byte)style_class->style;
+#ifdef FT_DEBUG_LEVEL_TRACE
+ else
+ FT_TRACE4(( "*" ));
+#endif
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !count )
+ FT_TRACE4(( "\n"
+ " (none)" ));
+ FT_TRACE4(( "\n\n" ));
+#endif
+
+ Exit:
+ hb_set_destroy( gsub_lookups );
+ hb_set_destroy( gsub_glyphs );
+ hb_set_destroy( gpos_lookups );
+ hb_set_destroy( gpos_glyphs );
+
+ return FT_Err_Ok;
+ }
+
+
+ /* construct HarfBuzz features */
+#undef COVERAGE
+#define COVERAGE( name, NAME, description, \
+ tag1, tag2, tag3, tag4 ) \
+ static const hb_feature_t name ## _feature[] = \
+ { \
+ { \
+ HB_TAG( tag1, tag2, tag3, tag4 ), \
+ 1, 0, (unsigned int)-1 \
+ } \
+ };
+
+
+#include "afcover.h"
+
+
+ /* define mapping between HarfBuzz features and AF_Coverage */
+#undef COVERAGE
+#define COVERAGE( name, NAME, description, \
+ tag1, tag2, tag3, tag4 ) \
+ name ## _feature,
+
+
+ static const hb_feature_t* features[] =
+ {
+#include "afcover.h"
+
+ NULL /* AF_COVERAGE_DEFAULT */
+ };
+
+
+ FT_Error
+ af_get_char_index( AF_StyleMetrics metrics,
+ FT_ULong charcode,
+ FT_ULong *codepoint,
+ FT_Long *y_offset )
+ {
+ AF_StyleClass style_class;
+
+ const hb_feature_t* feature;
+
+ FT_ULong in_idx, out_idx;
+
+
+ if ( !metrics )
+ return FT_THROW( Invalid_Argument );
+
+ in_idx = FT_Get_Char_Index( metrics->globals->face, charcode );
+
+ style_class = metrics->style_class;
+
+ feature = features[style_class->coverage];
+
+ if ( feature )
+ {
+ FT_UInt upem = metrics->globals->face->units_per_EM;
+
+ hb_font_t* font = metrics->globals->hb_font;
+ hb_buffer_t* buf = hb_buffer_create();
+
+ uint32_t c = (uint32_t)charcode;
+
+ hb_glyph_info_t* ginfo;
+ hb_glyph_position_t* gpos;
+ unsigned int gcount;
+
+
+ /* we shape at a size of units per EM; this means font units */
+ hb_font_set_scale( font, upem, upem );
+
+ /* XXX: is this sufficient for a single character of any script? */
+ hb_buffer_set_direction( buf, HB_DIRECTION_LTR );
+ hb_buffer_set_script( buf, scripts[style_class->script] );
+
+ /* we add one character to `buf' ... */
+ hb_buffer_add_utf32( buf, &c, 1, 0, 1 );
+
+ /* ... and apply one feature */
+ hb_shape( font, buf, feature, 1 );
+
+ ginfo = hb_buffer_get_glyph_infos( buf, &gcount );
+ gpos = hb_buffer_get_glyph_positions( buf, &gcount );
+
+ out_idx = ginfo[0].codepoint;
+
+ /* getting the same index indicates no substitution, */
+ /* which means that the glyph isn't available in the feature */
+ if ( in_idx == out_idx )
+ {
+ *codepoint = 0;
+ *y_offset = 0;
+ }
+ else
+ {
+ *codepoint = out_idx;
+ *y_offset = gpos[0].y_offset;
+ }
+
+ hb_buffer_destroy( buf );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( gcount > 1 )
+ FT_TRACE1(( "af_get_char_index:"
+ " input character mapped to multiple glyphs\n" ));
+#endif
+ }
+ else
+ {
+ *codepoint = in_idx;
+ *y_offset = 0;
+ }
+
+ return FT_Err_Ok;
+ }
+
+
+#else /* !FT_CONFIG_OPTION_USE_HARFBUZZ */
+
+
+ FT_Error
+ af_get_coverage( AF_FaceGlobals globals,
+ AF_StyleClass style_class,
+ FT_Byte* gstyles )
+ {
+ FT_UNUSED( globals );
+ FT_UNUSED( style_class );
+ FT_UNUSED( gstyles );
+
+ return FT_Err_Ok;
+ }
+
+
+ FT_Error
+ af_get_char_index( AF_StyleMetrics metrics,
+ FT_ULong charcode,
+ FT_ULong *codepoint,
+ FT_Long *y_offset )
+ {
+ FT_Face face;
+
+
+ if ( !metrics )
+ return FT_THROW( Invalid_Argument );
+
+ face = metrics->globals->face;
+
+ *codepoint = FT_Get_Char_Index( face, charcode );
+ *y_offset = 0;
+
+ return FT_Err_Ok;
+ }
+
+
+#endif /* !FT_CONFIG_OPTION_USE_HARFBUZZ */
+
+
+/* END */
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