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-rw-r--r--src/3rdparty/harfbuzz-ng/src/hb-buffer.h334
1 files changed, 304 insertions, 30 deletions
diff --git a/src/3rdparty/harfbuzz-ng/src/hb-buffer.h b/src/3rdparty/harfbuzz-ng/src/hb-buffer.h
index a8a4b84e97..f75fe96b21 100644
--- a/src/3rdparty/harfbuzz-ng/src/hb-buffer.h
+++ b/src/3rdparty/harfbuzz-ng/src/hb-buffer.h
@@ -27,7 +27,7 @@
* Google Author(s): Behdad Esfahbod
*/
-#ifndef HB_H_IN
+#if !defined(HB_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
#error "Include <hb.h> instead."
#endif
@@ -44,7 +44,6 @@ HB_BEGIN_DECLS
* hb_glyph_info_t:
* @codepoint: either a Unicode code point (before shaping) or a glyph index
* (after shaping).
- * @mask:
* @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
@@ -59,11 +58,12 @@ HB_BEGIN_DECLS
*
* 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;
- hb_mask_t mask; /* Holds hb_glyph_flags_t after hb_shape(), plus other things. */
+ /*< private >*/
+ hb_mask_t mask;
+ /*< public >*/
uint32_t cluster;
/*< private >*/
@@ -71,10 +71,98 @@ typedef struct hb_glyph_info_t {
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 is safe to break
+ * the glyph-run at the beginning of this
+ * cluster, and the two sides will 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.
+ * @HB_GLYPH_FLAG_UNSAFE_TO_CONCAT: Indicates that if input text is changed on one
+ * side of the beginning of the cluster this glyph
+ * is part of, then the shaping results for the
+ * other side might change.
+ * Note that the absence of this flag will NOT by
+ * itself mean that it IS safe to concat text.
+ * Only two pieces of text both of which clear of
+ * this flag can be concatenated safely.
+ * This can be used to optimize paragraph
+ * layout, by avoiding re-shaping of each line
+ * after line-breaking, by limiting the
+ * reshaping to a small piece around the
+ * breaking position only, even if the breaking
+ * position carries the
+ * #HB_GLYPH_FLAG_UNSAFE_TO_BREAK or when
+ * hyphenation or other text transformation
+ * happens at line-break position, in the following
+ * way:
+ * 1. Iterate back from the line-break position
+ * until the first cluster start position that is
+ * NOT unsafe-to-concat, 2. shape the segment from
+ * there till the end of line, 3. check whether the
+ * resulting glyph-run also is clear of the
+ * unsafe-to-concat at its start-of-text position;
+ * if it is, just splice it into place and the line
+ * is shaped; If not, move on to a position further
+ * back that is clear of unsafe-to-concat and retry
+ * from there, and repeat.
+ * At the start of next line a similar algorithm can
+ * be implemented. That is: 1. Iterate forward from
+ * the line-break position until the first cluster
+ * start position that is NOT unsafe-to-concat, 2.
+ * shape the segment from beginning of the line to
+ * that position, 3. check whether the resulting
+ * glyph-run also is clear of the unsafe-to-concat
+ * at its end-of-text position; if it is, just splice
+ * it into place and the beginning is shaped; If not,
+ * move on to a position further forward that is clear
+ * of unsafe-to-concat and retry up to there, and repeat.
+ * A slight complication will arise in the
+ * implementation of the algorithm above,
+ * because while our buffer API has a way to
+ * return flags for position corresponding to
+ * start-of-text, there is currently no position
+ * corresponding to end-of-text. This limitation
+ * can be alleviated by shaping more text than needed
+ * and looking for unsafe-to-concat flag within text
+ * clusters.
+ * The #HB_GLYPH_FLAG_UNSAFE_TO_BREAK flag will
+ * always imply this flag.
+ * To use this flag, you must enable the buffer flag
+ * @HB_BUFFER_FLAG_PRODUCE_UNSAFE_TO_CONCAT during
+ * shaping, otherwise the buffer flag will not be
+ * reliably produced.
+ * Since: 4.0.0
+ * @HB_GLYPH_FLAG_SAFE_TO_INSERT_TATWEEL: In scripts that use elongation (Arabic,
+ Mongolian, Syriac, etc.), this flag signifies
+ that it is safe to insert a U+0640 TATWEEL
+ character before this cluster for elongation.
+ This flag does not determine the
+ script-specific elongation places, but only
+ when it is safe to do the elongation without
+ interrupting text shaping.
+ Since: 5.1.0
+ * @HB_GLYPH_FLAG_DEFINED: All the currently defined flags.
+ *
+ * Flags for #hb_glyph_info_t.
+ *
+ * Since: 1.5.0
+ */
typedef enum { /*< flags >*/
- HB_GLYPH_FLAG_UNSAFE_TO_BREAK = 0x00000001,
+ HB_GLYPH_FLAG_UNSAFE_TO_BREAK = 0x00000001,
+ HB_GLYPH_FLAG_UNSAFE_TO_CONCAT = 0x00000002,
+ HB_GLYPH_FLAG_SAFE_TO_INSERT_TATWEEL = 0x00000004,
- HB_GLYPH_FLAG_DEFINED = 0x00000001 /* OR of all defined flags */
+ HB_GLYPH_FLAG_DEFINED = 0x00000007 /* OR of all defined flags */
} hb_glyph_flags_t;
HB_EXTERN hb_glyph_flags_t
@@ -129,6 +217,11 @@ typedef struct hb_segment_properties_t {
void *reserved2;
} hb_segment_properties_t;
+/**
+ * HB_SEGMENT_PROPERTIES_DEFAULT:
+ *
+ * The default #hb_segment_properties_t of of freshly created #hb_buffer_t.
+ */
#define HB_SEGMENT_PROPERTIES_DEFAULT {HB_DIRECTION_INVALID, \
HB_SCRIPT_INVALID, \
HB_LANGUAGE_INVALID, \
@@ -142,6 +235,9 @@ hb_segment_properties_equal (const hb_segment_properties_t *a,
HB_EXTERN unsigned int
hb_segment_properties_hash (const hb_segment_properties_t *p);
+HB_EXTERN void
+hb_segment_properties_overlay (hb_segment_properties_t *p,
+ const hb_segment_properties_t *src);
/**
@@ -157,6 +253,13 @@ HB_EXTERN hb_buffer_t *
hb_buffer_create (void);
HB_EXTERN hb_buffer_t *
+hb_buffer_create_similar (const hb_buffer_t *src);
+
+HB_EXTERN void
+hb_buffer_reset (hb_buffer_t *buffer);
+
+
+HB_EXTERN hb_buffer_t *
hb_buffer_get_empty (void);
HB_EXTERN hb_buffer_t *
@@ -173,7 +276,7 @@ hb_buffer_set_user_data (hb_buffer_t *buffer,
hb_bool_t replace);
HB_EXTERN void *
-hb_buffer_get_user_data (hb_buffer_t *buffer,
+hb_buffer_get_user_data (const hb_buffer_t *buffer,
hb_user_data_key_t *key);
@@ -182,6 +285,8 @@ hb_buffer_get_user_data (hb_buffer_t *buffer,
* @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).
+ *
+ * The type of #hb_buffer_t contents.
*/
typedef enum {
HB_BUFFER_CONTENT_TYPE_INVALID = 0,
@@ -194,7 +299,7 @@ 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_buffer_get_content_type (const hb_buffer_t *buffer);
HB_EXTERN void
@@ -202,21 +307,21 @@ 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_buffer_get_unicode_funcs (const 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_buffer_get_direction (const 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_buffer_get_script (const hb_buffer_t *buffer);
HB_EXTERN void
hb_buffer_set_language (hb_buffer_t *buffer,
@@ -224,14 +329,14 @@ hb_buffer_set_language (hb_buffer_t *buffer,
HB_EXTERN hb_language_t
-hb_buffer_get_language (hb_buffer_t *buffer);
+hb_buffer_get_language (const 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_buffer_get_segment_properties (const hb_buffer_t *buffer,
hb_segment_properties_t *props);
HB_EXTERN void
@@ -247,13 +352,44 @@ hb_buffer_guess_segment_properties (hb_buffer_t *buffer);
* 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_EOT.
+ * @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 (currently done
- * by replacing them with the space glyph and zeroing the
- * advance width.)
+ * 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: 2.4.0
+ * @HB_BUFFER_FLAG_VERIFY:
+ * flag indicating that the hb_shape() call and its variants
+ * should perform various verification processes on the results
+ * of the shaping operation on the buffer. If the verification
+ * fails, then either a buffer message is sent, if a message
+ * handler is installed on the buffer, or a message is written
+ * to standard error. In either case, the shaping result might
+ * be modified to show the failed output. Since: 3.4.0
+ * @HB_BUFFER_FLAG_PRODUCE_UNSAFE_TO_CONCAT:
+ * flag indicating that the @HB_GLYPH_FLAG_UNSAFE_TO_CONCAT
+ * glyph-flag should be produced by the shaper. By default
+ * it will not be produced since it incurs a cost. Since: 4.0.0
+ * @HB_BUFFER_FLAG_PRODUCE_SAFE_TO_INSERT_TATWEEL:
+ * flag indicating that the @HB_GLYPH_FLAG_SAFE_TO_INSERT_TATWEEL
+ * glyph-flag should be produced by the shaper. By default
+ * it will not be produced. Since: 5.1.0
+ * @HB_BUFFER_FLAG_DEFINED: All currently defined flags: Since: 4.4.0
+ *
+ * Flags for #hb_buffer_t.
*
* Since: 0.9.20
*/
@@ -261,7 +397,14 @@ 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_PRESERVE_DEFAULT_IGNORABLES = 0x00000004u,
+ HB_BUFFER_FLAG_REMOVE_DEFAULT_IGNORABLES = 0x00000008u,
+ HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE = 0x00000010u,
+ HB_BUFFER_FLAG_VERIFY = 0x00000020u,
+ HB_BUFFER_FLAG_PRODUCE_UNSAFE_TO_CONCAT = 0x00000040u,
+ HB_BUFFER_FLAG_PRODUCE_SAFE_TO_INSERT_TATWEEL = 0x00000080u,
+
+ HB_BUFFER_FLAG_DEFINED = 0x000000FFu
} hb_buffer_flags_t;
HB_EXTERN void
@@ -269,9 +412,34 @@ 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_get_flags (const 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 {
@@ -286,7 +454,7 @@ 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_get_cluster_level (const hb_buffer_t *buffer);
/**
* HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT:
@@ -303,18 +471,39 @@ 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_buffer_get_replacement_codepoint (const 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 (const hb_buffer_t *buffer);
HB_EXTERN void
-hb_buffer_reset (hb_buffer_t *buffer);
+hb_buffer_set_not_found_glyph (hb_buffer_t *buffer,
+ hb_codepoint_t not_found);
+
+HB_EXTERN hb_codepoint_t
+hb_buffer_get_not_found_glyph (const hb_buffer_t *buffer);
+
+HB_EXTERN void
+hb_buffer_set_random_state (hb_buffer_t *buffer,
+ unsigned state);
+
+HB_EXTERN unsigned
+hb_buffer_get_random_state (const hb_buffer_t *buffer);
+
+/*
+ * Content API.
+ */
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);
+ unsigned int size);
HB_EXTERN hb_bool_t
@@ -375,7 +564,7 @@ hb_buffer_add_codepoints (hb_buffer_t *buffer,
HB_EXTERN void
hb_buffer_append (hb_buffer_t *buffer,
- hb_buffer_t *source,
+ const hb_buffer_t *source,
unsigned int start,
unsigned int end);
@@ -384,17 +573,20 @@ hb_buffer_set_length (hb_buffer_t *buffer,
unsigned int length);
HB_EXTERN unsigned int
-hb_buffer_get_length (hb_buffer_t *buffer);
+hb_buffer_get_length (const 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);
+ unsigned int *length);
HB_EXTERN hb_glyph_position_t *
hb_buffer_get_glyph_positions (hb_buffer_t *buffer,
- unsigned int *length);
+ unsigned int *length);
+
+HB_EXTERN hb_bool_t
+hb_buffer_has_positions (hb_buffer_t *buffer);
HB_EXTERN void
@@ -412,6 +604,10 @@ hb_buffer_normalize_glyphs (hb_buffer_t *buffer);
* @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
+ * @HB_BUFFER_SERIALIZE_FLAG_DEFINED: All currently defined flags. Since: 4.4.0
*
* Flags that control what glyph information are serialized in hb_buffer_serialize_glyphs().
*
@@ -423,7 +619,10 @@ typedef enum { /*< flags >*/
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_GLYPH_FLAGS = 0x00000010u,
+ HB_BUFFER_SERIALIZE_FLAG_NO_ADVANCES = 0x00000020u,
+
+ HB_BUFFER_SERIALIZE_FLAG_DEFINED = 0x0000003Fu
} hb_buffer_serialize_flags_t;
/**
@@ -463,6 +662,27 @@ hb_buffer_serialize_glyphs (hb_buffer_t *buffer,
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,
@@ -471,11 +691,48 @@ hb_buffer_deserialize_glyphs (hb_buffer_t *buffer,
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
*/
+/**
+ * hb_buffer_diff_flags_t:
+ * @HB_BUFFER_DIFF_FLAG_EQUAL: equal buffers.
+ * @HB_BUFFER_DIFF_FLAG_CONTENT_TYPE_MISMATCH: buffers with different
+ * #hb_buffer_content_type_t.
+ * @HB_BUFFER_DIFF_FLAG_LENGTH_MISMATCH: buffers with differing length.
+ * @HB_BUFFER_DIFF_FLAG_NOTDEF_PRESENT: `.notdef` glyph is present in the
+ * reference buffer.
+ * @HB_BUFFER_DIFF_FLAG_DOTTED_CIRCLE_PRESENT: dotted circle glyph is present
+ * in the reference buffer.
+ * @HB_BUFFER_DIFF_FLAG_CODEPOINT_MISMATCH: difference in #hb_glyph_info_t.codepoint
+ * @HB_BUFFER_DIFF_FLAG_CLUSTER_MISMATCH: difference in #hb_glyph_info_t.cluster
+ * @HB_BUFFER_DIFF_FLAG_GLYPH_FLAGS_MISMATCH: difference in #hb_glyph_flags_t.
+ * @HB_BUFFER_DIFF_FLAG_POSITION_MISMATCH: difference in #hb_glyph_position_t.
+ *
+ * Flags from comparing two #hb_buffer_t's.
+ *
+ * Buffer with different #hb_buffer_content_type_t cannot be meaningfully
+ * compared in any further detail.
+ *
+ * For buffers with differing length, the per-glyph comparison is not
+ * attempted, though we do still scan reference buffer for dotted circle and
+ * `.notdef` glyphs.
+ *
+ * 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.
+ *
+ * Since: 1.5.0
+ */
typedef enum { /*< flags >*/
HB_BUFFER_DIFF_FLAG_EQUAL = 0x0000,
@@ -512,9 +769,26 @@ hb_buffer_diff (hb_buffer_t *buffer,
/*
- * Debugging.
+ * Tracing.
*/
+/**
+ * hb_buffer_message_func_t:
+ * @buffer: An #hb_buffer_t to work upon
+ * @font: The #hb_font_t the @buffer is shaped with
+ * @message: `NULL`-terminated message passed to the function
+ * @user_data: User data pointer passed by the caller
+ *
+ * A callback method for #hb_buffer_t. The method gets called with the
+ * #hb_buffer_t it was set on, the #hb_font_t the buffer is shaped with and a
+ * message describing what step of the shaping process will be performed.
+ * Returning `false` from this method will skip this shaping step and move to
+ * the next one.
+ *
+ * Return value: `true` to perform the shaping step, `false` to skip it.
+ *
+ * Since: 1.1.3
+ */
typedef hb_bool_t (*hb_buffer_message_func_t) (hb_buffer_t *buffer,
hb_font_t *font,
const char *message,