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Edit File: hb-buffer.h
/* * Copyright © 1998-2004 David Turner and Werner Lemberg * Copyright © 2004,2007,2009 Red Hat, Inc. * Copyright © 2011,2012 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. * * Red Hat Author(s): Owen Taylor, Behdad Esfahbod * Google Author(s): Behdad Esfahbod */ #ifndef HB_H_IN #error "Include <hb.h> instead." #endif #ifndef HB_BUFFER_H #define HB_BUFFER_H #include "hb-common.h" #include "hb-unicode.h" #include "hb-font.h" HB_BEGIN_DECLS /** * hb_glyph_info_t: * @codepoint: either a Unicode code point (before shaping) or a glyph index * (after shaping). * @cluster: the index of the character in the original text that corresponds * to this #hb_glyph_info_t, or whatever the client passes to * hb_buffer_add(). More than one #hb_glyph_info_t can have the same * @cluster value, if they resulted from the same character (e.g. one * to many glyph substitution), and when more than one character gets * merged in the same glyph (e.g. many to one glyph substitution) the * #hb_glyph_info_t will have the smallest cluster value of them. * By default some characters are merged into the same cluster * (e.g. combining marks have the same cluster as their bases) * even if they are separate glyphs, hb_buffer_set_cluster_level() * allow selecting more fine-grained cluster handling. * * The #hb_glyph_info_t is the structure that holds information about the * glyphs and their relation to input text. */ typedef struct hb_glyph_info_t { hb_codepoint_t codepoint; /*< private >*/ hb_mask_t mask; /*< public >*/ uint32_t cluster; /*< private >*/ hb_var_int_t var1; hb_var_int_t var2; } hb_glyph_info_t; /** * hb_glyph_flags_t: * @HB_GLYPH_FLAG_UNSAFE_TO_BREAK: Indicates that if input text is broken at the * beginning of the cluster this glyph is part of, * then both sides need to be re-shaped, as the * result might be different. On the flip side, * it means that when this flag is not present, * then it's safe to break the glyph-run at the * beginning of this cluster, and the two sides * represent the exact same result one would get * if breaking input text at the beginning of * this cluster and shaping the two sides * separately. This can be used to optimize * paragraph layout, by avoiding re-shaping * of each line after line-breaking, or limiting * the reshaping to a small piece around the * breaking point only. * @HB_GLYPH_FLAG_DEFINED: All the currently defined flags. * * Since: 1.5.0 */ typedef enum { /*< flags >*/ HB_GLYPH_FLAG_UNSAFE_TO_BREAK = 0x00000001, HB_GLYPH_FLAG_DEFINED = 0x00000001 /* OR of all defined flags */ } hb_glyph_flags_t; HB_EXTERN hb_glyph_flags_t hb_glyph_info_get_glyph_flags (const hb_glyph_info_t *info); #define hb_glyph_info_get_glyph_flags(info) \ ((hb_glyph_flags_t) ((unsigned int) (info)->mask & HB_GLYPH_FLAG_DEFINED)) /** * hb_glyph_position_t: * @x_advance: how much the line advances after drawing this glyph when setting * text in horizontal direction. * @y_advance: how much the line advances after drawing this glyph when setting * text in vertical direction. * @x_offset: how much the glyph moves on the X-axis before drawing it, this * should not affect how much the line advances. * @y_offset: how much the glyph moves on the Y-axis before drawing it, this * should not affect how much the line advances. * * The #hb_glyph_position_t is the structure that holds the positions of the * glyph in both horizontal and vertical directions. All positions in * #hb_glyph_position_t are relative to the current point. * */ typedef struct hb_glyph_position_t { hb_position_t x_advance; hb_position_t y_advance; hb_position_t x_offset; hb_position_t y_offset; /*< private >*/ hb_var_int_t var; } hb_glyph_position_t; /** * hb_segment_properties_t: * @direction: the #hb_direction_t of the buffer, see hb_buffer_set_direction(). * @script: the #hb_script_t of the buffer, see hb_buffer_set_script(). * @language: the #hb_language_t of the buffer, see hb_buffer_set_language(). * * The structure that holds various text properties of an #hb_buffer_t. Can be * set and retrieved using hb_buffer_set_segment_properties() and * hb_buffer_get_segment_properties(), respectively. */ typedef struct hb_segment_properties_t { hb_direction_t direction; hb_script_t script; hb_language_t language; /*< private >*/ void *reserved1; void *reserved2; } hb_segment_properties_t; #define HB_SEGMENT_PROPERTIES_DEFAULT {HB_DIRECTION_INVALID, \ HB_SCRIPT_INVALID, \ HB_LANGUAGE_INVALID, \ (void *) 0, \ (void *) 0} HB_EXTERN hb_bool_t hb_segment_properties_equal (const hb_segment_properties_t *a, const hb_segment_properties_t *b); HB_EXTERN unsigned int hb_segment_properties_hash (const hb_segment_properties_t *p); /** * hb_buffer_t: * * The main structure holding the input text and its properties before shaping, * and output glyphs and their information after shaping. */ typedef struct hb_buffer_t hb_buffer_t; HB_EXTERN hb_buffer_t * hb_buffer_create (void); HB_EXTERN hb_buffer_t * hb_buffer_get_empty (void); HB_EXTERN hb_buffer_t * hb_buffer_reference (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_destroy (hb_buffer_t *buffer); HB_EXTERN hb_bool_t hb_buffer_set_user_data (hb_buffer_t *buffer, hb_user_data_key_t *key, void * data, hb_destroy_func_t destroy, hb_bool_t replace); HB_EXTERN void * hb_buffer_get_user_data (hb_buffer_t *buffer, hb_user_data_key_t *key); /** * hb_buffer_content_type_t: * @HB_BUFFER_CONTENT_TYPE_INVALID: Initial value for new buffer. * @HB_BUFFER_CONTENT_TYPE_UNICODE: The buffer contains input characters (before shaping). * @HB_BUFFER_CONTENT_TYPE_GLYPHS: The buffer contains output glyphs (after shaping). */ typedef enum { HB_BUFFER_CONTENT_TYPE_INVALID = 0, HB_BUFFER_CONTENT_TYPE_UNICODE, HB_BUFFER_CONTENT_TYPE_GLYPHS } hb_buffer_content_type_t; HB_EXTERN void hb_buffer_set_content_type (hb_buffer_t *buffer, hb_buffer_content_type_t content_type); HB_EXTERN hb_buffer_content_type_t hb_buffer_get_content_type (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_unicode_funcs (hb_buffer_t *buffer, hb_unicode_funcs_t *unicode_funcs); HB_EXTERN hb_unicode_funcs_t * hb_buffer_get_unicode_funcs (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_direction (hb_buffer_t *buffer, hb_direction_t direction); HB_EXTERN hb_direction_t hb_buffer_get_direction (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_script (hb_buffer_t *buffer, hb_script_t script); HB_EXTERN hb_script_t hb_buffer_get_script (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_language (hb_buffer_t *buffer, hb_language_t language); HB_EXTERN hb_language_t hb_buffer_get_language (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_segment_properties (hb_buffer_t *buffer, const hb_segment_properties_t *props); HB_EXTERN void hb_buffer_get_segment_properties (hb_buffer_t *buffer, hb_segment_properties_t *props); HB_EXTERN void hb_buffer_guess_segment_properties (hb_buffer_t *buffer); /** * hb_buffer_flags_t: * @HB_BUFFER_FLAG_DEFAULT: the default buffer flag. * @HB_BUFFER_FLAG_BOT: flag indicating that special handling of the beginning * of text paragraph can be applied to this buffer. Should usually * be set, unless you are passing to the buffer only part * of the text without the full context. * @HB_BUFFER_FLAG_EOT: flag indicating that special handling of the end of text * paragraph can be applied to this buffer, similar to * @HB_BUFFER_FLAG_BOT. * @HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES: * flag indication that character with Default_Ignorable * Unicode property should use the corresponding glyph * from the font, instead of hiding them (done by * replacing them with the space glyph and zeroing the * advance width.) This flag takes precedence over * @HB_BUFFER_FLAG_REMOVE_DEFAULT_IGNORABLES. * @HB_BUFFER_FLAG_REMOVE_DEFAULT_IGNORABLES: * flag indication that character with Default_Ignorable * Unicode property should be removed from glyph string * instead of hiding them (done by replacing them with the * space glyph and zeroing the advance width.) * @HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES takes * precedence over this flag. Since: 1.8.0 * @HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE: * flag indicating that a dotted circle should * not be inserted in the rendering of incorrect * character sequences (such at <0905 093E>). Since: 2.4 * * Since: 0.9.20 */ typedef enum { /*< flags >*/ HB_BUFFER_FLAG_DEFAULT = 0x00000000u, HB_BUFFER_FLAG_BOT = 0x00000001u, /* Beginning-of-text */ HB_BUFFER_FLAG_EOT = 0x00000002u, /* End-of-text */ HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES = 0x00000004u, HB_BUFFER_FLAG_REMOVE_DEFAULT_IGNORABLES = 0x00000008u, HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE = 0x00000010u } hb_buffer_flags_t; HB_EXTERN void hb_buffer_set_flags (hb_buffer_t *buffer, hb_buffer_flags_t flags); HB_EXTERN hb_buffer_flags_t hb_buffer_get_flags (hb_buffer_t *buffer); /** * hb_buffer_cluster_level_t: * @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES: Return cluster values grouped by graphemes into * monotone order. * @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS: Return cluster values grouped into monotone order. * @HB_BUFFER_CLUSTER_LEVEL_CHARACTERS: Don't group cluster values. * @HB_BUFFER_CLUSTER_LEVEL_DEFAULT: Default cluster level, * equal to @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES. * * Data type for holding HarfBuzz's clustering behavior options. The cluster level * dictates one aspect of how HarfBuzz will treat non-base characters * during shaping. * * In @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES, non-base * characters are merged into the cluster of the base character that precedes them. * * In @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS, non-base characters are initially * assigned their own cluster values, which are not merged into preceding base * clusters. This allows HarfBuzz to perform additional operations like reorder * sequences of adjacent marks. * * @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES is the default, because it maintains * backward compatibility with older versions of HarfBuzz. New client programs that * do not need to maintain such backward compatibility are recommended to use * @HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS instead of the default. * * Since: 0.9.42 */ typedef enum { HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES = 0, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS = 1, HB_BUFFER_CLUSTER_LEVEL_CHARACTERS = 2, HB_BUFFER_CLUSTER_LEVEL_DEFAULT = HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES } hb_buffer_cluster_level_t; HB_EXTERN void hb_buffer_set_cluster_level (hb_buffer_t *buffer, hb_buffer_cluster_level_t cluster_level); HB_EXTERN hb_buffer_cluster_level_t hb_buffer_get_cluster_level (hb_buffer_t *buffer); /** * HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT: * * The default code point for replacing invalid characters in a given encoding. * Set to U+FFFD REPLACEMENT CHARACTER. * * Since: 0.9.31 */ #define HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT 0xFFFDu HB_EXTERN void hb_buffer_set_replacement_codepoint (hb_buffer_t *buffer, hb_codepoint_t replacement); HB_EXTERN hb_codepoint_t hb_buffer_get_replacement_codepoint (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_set_invisible_glyph (hb_buffer_t *buffer, hb_codepoint_t invisible); HB_EXTERN hb_codepoint_t hb_buffer_get_invisible_glyph (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_reset (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_clear_contents (hb_buffer_t *buffer); HB_EXTERN hb_bool_t hb_buffer_pre_allocate (hb_buffer_t *buffer, unsigned int size); HB_EXTERN hb_bool_t hb_buffer_allocation_successful (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_reverse (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_reverse_range (hb_buffer_t *buffer, unsigned int start, unsigned int end); HB_EXTERN void hb_buffer_reverse_clusters (hb_buffer_t *buffer); /* Filling the buffer in */ HB_EXTERN void hb_buffer_add (hb_buffer_t *buffer, hb_codepoint_t codepoint, unsigned int cluster); HB_EXTERN void hb_buffer_add_utf8 (hb_buffer_t *buffer, const char *text, int text_length, unsigned int item_offset, int item_length); HB_EXTERN void hb_buffer_add_utf16 (hb_buffer_t *buffer, const uint16_t *text, int text_length, unsigned int item_offset, int item_length); HB_EXTERN void hb_buffer_add_utf32 (hb_buffer_t *buffer, const uint32_t *text, int text_length, unsigned int item_offset, int item_length); HB_EXTERN void hb_buffer_add_latin1 (hb_buffer_t *buffer, const uint8_t *text, int text_length, unsigned int item_offset, int item_length); HB_EXTERN void hb_buffer_add_codepoints (hb_buffer_t *buffer, const hb_codepoint_t *text, int text_length, unsigned int item_offset, int item_length); HB_EXTERN void hb_buffer_append (hb_buffer_t *buffer, hb_buffer_t *source, unsigned int start, unsigned int end); HB_EXTERN hb_bool_t hb_buffer_set_length (hb_buffer_t *buffer, unsigned int length); HB_EXTERN unsigned int hb_buffer_get_length (hb_buffer_t *buffer); /* Getting glyphs out of the buffer */ HB_EXTERN hb_glyph_info_t * hb_buffer_get_glyph_infos (hb_buffer_t *buffer, unsigned int *length); HB_EXTERN hb_glyph_position_t * hb_buffer_get_glyph_positions (hb_buffer_t *buffer, unsigned int *length); HB_EXTERN hb_bool_t hb_buffer_has_positions (hb_buffer_t *buffer); HB_EXTERN void hb_buffer_normalize_glyphs (hb_buffer_t *buffer); /* * Serialize */ /** * hb_buffer_serialize_flags_t: * @HB_BUFFER_SERIALIZE_FLAG_DEFAULT: serialize glyph names, clusters and positions. * @HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS: do not serialize glyph cluster. * @HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS: do not serialize glyph position information. * @HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES: do no serialize glyph name. * @HB_BUFFER_SERIALIZE_FLAG_GLYPH_EXTENTS: serialize glyph extents. * @HB_BUFFER_SERIALIZE_FLAG_GLYPH_FLAGS: serialize glyph flags. Since: 1.5.0 * @HB_BUFFER_SERIALIZE_FLAG_NO_ADVANCES: do not serialize glyph advances, * glyph offsets will reflect absolute glyph positions. Since: 1.8.0 * * Flags that control what glyph information are serialized in hb_buffer_serialize_glyphs(). * * Since: 0.9.20 */ typedef enum { /*< flags >*/ HB_BUFFER_SERIALIZE_FLAG_DEFAULT = 0x00000000u, HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS = 0x00000001u, HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS = 0x00000002u, HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES = 0x00000004u, HB_BUFFER_SERIALIZE_FLAG_GLYPH_EXTENTS = 0x00000008u, HB_BUFFER_SERIALIZE_FLAG_GLYPH_FLAGS = 0x00000010u, HB_BUFFER_SERIALIZE_FLAG_NO_ADVANCES = 0x00000020u } hb_buffer_serialize_flags_t; /** * hb_buffer_serialize_format_t: * @HB_BUFFER_SERIALIZE_FORMAT_TEXT: a human-readable, plain text format. * @HB_BUFFER_SERIALIZE_FORMAT_JSON: a machine-readable JSON format. * @HB_BUFFER_SERIALIZE_FORMAT_INVALID: invalid format. * * The buffer serialization and de-serialization format used in * hb_buffer_serialize_glyphs() and hb_buffer_deserialize_glyphs(). * * Since: 0.9.2 */ typedef enum { HB_BUFFER_SERIALIZE_FORMAT_TEXT = HB_TAG('T','E','X','T'), HB_BUFFER_SERIALIZE_FORMAT_JSON = HB_TAG('J','S','O','N'), HB_BUFFER_SERIALIZE_FORMAT_INVALID = HB_TAG_NONE } hb_buffer_serialize_format_t; HB_EXTERN hb_buffer_serialize_format_t hb_buffer_serialize_format_from_string (const char *str, int len); HB_EXTERN const char * hb_buffer_serialize_format_to_string (hb_buffer_serialize_format_t format); HB_EXTERN const char ** hb_buffer_serialize_list_formats (void); HB_EXTERN unsigned int hb_buffer_serialize_glyphs (hb_buffer_t *buffer, unsigned int start, unsigned int end, char *buf, unsigned int buf_size, unsigned int *buf_consumed, hb_font_t *font, hb_buffer_serialize_format_t format, hb_buffer_serialize_flags_t flags); HB_EXTERN unsigned int hb_buffer_serialize_unicode (hb_buffer_t *buffer, unsigned int start, unsigned int end, char *buf, unsigned int buf_size, unsigned int *buf_consumed, hb_buffer_serialize_format_t format, hb_buffer_serialize_flags_t flags); HB_EXTERN unsigned int hb_buffer_serialize (hb_buffer_t *buffer, unsigned int start, unsigned int end, char *buf, unsigned int buf_size, unsigned int *buf_consumed, hb_font_t *font, hb_buffer_serialize_format_t format, hb_buffer_serialize_flags_t flags); HB_EXTERN hb_bool_t hb_buffer_deserialize_glyphs (hb_buffer_t *buffer, const char *buf, int buf_len, const char **end_ptr, hb_font_t *font, hb_buffer_serialize_format_t format); HB_EXTERN hb_bool_t hb_buffer_deserialize_unicode (hb_buffer_t *buffer, const char *buf, int buf_len, const char **end_ptr, hb_buffer_serialize_format_t format); /* * Compare buffers */ typedef enum { /*< flags >*/ HB_BUFFER_DIFF_FLAG_EQUAL = 0x0000, /* Buffers with different content_type cannot be meaningfully compared * in any further detail. */ HB_BUFFER_DIFF_FLAG_CONTENT_TYPE_MISMATCH = 0x0001, /* For buffers with differing length, the per-glyph comparison is not * attempted, though we do still scan reference for dottedcircle / .notdef * glyphs. */ HB_BUFFER_DIFF_FLAG_LENGTH_MISMATCH = 0x0002, /* We want to know if dottedcircle / .notdef glyphs are present in the * reference, as we may not care so much about other differences in this * case. */ HB_BUFFER_DIFF_FLAG_NOTDEF_PRESENT = 0x0004, HB_BUFFER_DIFF_FLAG_DOTTED_CIRCLE_PRESENT = 0x0008, /* If the buffers have the same length, we compare them glyph-by-glyph * and report which aspect(s) of the glyph info/position are different. */ HB_BUFFER_DIFF_FLAG_CODEPOINT_MISMATCH = 0x0010, HB_BUFFER_DIFF_FLAG_CLUSTER_MISMATCH = 0x0020, HB_BUFFER_DIFF_FLAG_GLYPH_FLAGS_MISMATCH = 0x0040, HB_BUFFER_DIFF_FLAG_POSITION_MISMATCH = 0x0080 } hb_buffer_diff_flags_t; /* Compare the contents of two buffers, report types of differences. */ HB_EXTERN hb_buffer_diff_flags_t hb_buffer_diff (hb_buffer_t *buffer, hb_buffer_t *reference, hb_codepoint_t dottedcircle_glyph, unsigned int position_fuzz); /* * Debugging. */ typedef hb_bool_t (*hb_buffer_message_func_t) (hb_buffer_t *buffer, hb_font_t *font, const char *message, void *user_data); HB_EXTERN void hb_buffer_set_message_func (hb_buffer_t *buffer, hb_buffer_message_func_t func, void *user_data, hb_destroy_func_t destroy); HB_END_DECLS #endif /* HB_BUFFER_H */