[MPlayer-cvslog] r34388 - in trunk/libass: ass_shaper.c ass_shaper.h

reimar subversion at mplayerhq.hu
Sun Dec 4 00:08:03 CET 2011


Author: reimar
Date: Sun Dec  4 00:08:03 2011
New Revision: 34388

Log:
Commit added forgotten in previous commit.

Added:
   trunk/libass/ass_shaper.c
   trunk/libass/ass_shaper.h

Added: trunk/libass/ass_shaper.c
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ trunk/libass/ass_shaper.c	Sun Dec  4 00:08:03 2011	(r34388)
@@ -0,0 +1,733 @@
+/*
+ * Copyright (C) 2011 Grigori Goronzy <greg at chown.ath.cx>
+ *
+ * This file is part of libass.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "config.h"
+
+#include <fribidi/fribidi.h>
+
+#include "ass_shaper.h"
+#include "ass_render.h"
+#include "ass_font.h"
+#include "ass_parse.h"
+#include "ass_cache.h"
+
+#define MAX_RUNS 50
+
+#ifdef CONFIG_HARFBUZZ
+#include <hb-ft.h>
+enum {
+    VERT = 0,
+    VKNA,
+    KERN
+};
+#define NUM_FEATURES 3
+#endif
+
+struct ass_shaper {
+    ASS_ShapingLevel shaping_level;
+
+    // FriBidi log2vis
+    int n_glyphs;
+    FriBidiChar *event_text;
+    FriBidiCharType *ctypes;
+    FriBidiLevel *emblevels;
+    FriBidiStrIndex *cmap;
+    FriBidiParType base_direction;
+
+#ifdef CONFIG_HARFBUZZ
+    // OpenType features
+    int n_features;
+    hb_feature_t *features;
+    hb_language_t language;
+
+    // Glyph metrics cache, to speed up shaping
+    Cache *metrics_cache;
+#endif
+};
+
+#ifdef CONFIG_HARFBUZZ
+struct ass_shaper_metrics_data {
+    Cache *metrics_cache;
+    GlyphMetricsHashKey hash_key;
+    int vertical;
+};
+
+struct ass_shaper_font_data {
+    hb_font_t *fonts[ASS_FONT_MAX_FACES];
+    hb_font_funcs_t *font_funcs[ASS_FONT_MAX_FACES];
+    struct ass_shaper_metrics_data *metrics_data[ASS_FONT_MAX_FACES];
+};
+#endif
+
+/**
+ * \brief Print version information
+ */
+void ass_shaper_info(ASS_Library *lib)
+{
+    ass_msg(lib, MSGL_V, "Shaper: FriBidi "
+            FRIBIDI_VERSION " (SIMPLE)"
+#ifdef CONFIG_HARFBUZZ
+            " HarfBuzz-ng %s (COMPLEX)", hb_version_string()
+#endif
+           );
+}
+
+/**
+ * \brief grow arrays, if needed
+ * \param new_size requested size
+ */
+static void check_allocations(ASS_Shaper *shaper, size_t new_size)
+{
+    if (new_size > shaper->n_glyphs) {
+        shaper->event_text = realloc(shaper->event_text, sizeof(FriBidiChar) * new_size);
+        shaper->ctypes     = realloc(shaper->ctypes, sizeof(FriBidiCharType) * new_size);
+        shaper->emblevels  = realloc(shaper->emblevels, sizeof(FriBidiLevel) * new_size);
+        shaper->cmap       = realloc(shaper->cmap, sizeof(FriBidiStrIndex) * new_size);
+    }
+}
+
+/**
+ * \brief Free shaper and related data
+ */
+void ass_shaper_free(ASS_Shaper *shaper)
+{
+#ifdef CONFIG_HARFBUZZ
+    ass_cache_done(shaper->metrics_cache);
+    free(shaper->features);
+#endif
+    free(shaper->event_text);
+    free(shaper->ctypes);
+    free(shaper->emblevels);
+    free(shaper->cmap);
+    free(shaper);
+}
+
+void ass_shaper_font_data_free(ASS_ShaperFontData *priv)
+{
+#ifdef CONFIG_HARFBUZZ
+    int i;
+    for (i = 0; i < ASS_FONT_MAX_FACES; i++)
+        if (priv->fonts[i]) {
+            free(priv->metrics_data[i]);
+            hb_font_destroy(priv->fonts[i]);
+            hb_font_funcs_destroy(priv->font_funcs[i]);
+        }
+    free(priv);
+#endif
+}
+
+#ifdef CONFIG_HARFBUZZ
+/**
+ * \brief set up the HarfBuzz OpenType feature list with some
+ * standard features.
+ */
+static void init_features(ASS_Shaper *shaper)
+{
+    shaper->features = calloc(sizeof(hb_feature_t), NUM_FEATURES);
+
+    shaper->n_features = NUM_FEATURES;
+    shaper->features[VERT].tag = HB_TAG('v', 'e', 'r', 't');
+    shaper->features[VERT].end = INT_MAX;
+    shaper->features[VKNA].tag = HB_TAG('v', 'k', 'n', 'a');
+    shaper->features[VKNA].end = INT_MAX;
+    shaper->features[KERN].tag = HB_TAG('k', 'e', 'r', 'n');
+    shaper->features[KERN].end = INT_MAX;
+}
+
+/**
+ * \brief Set features depending on properties of the run
+ */
+static void set_run_features(ASS_Shaper *shaper, GlyphInfo *info)
+{
+        // enable vertical substitutions for @font runs
+        if (info->font->desc.vertical)
+            shaper->features[VERT].value = shaper->features[VKNA].value = 1;
+        else
+            shaper->features[VERT].value = shaper->features[VKNA].value = 0;
+}
+
+/**
+ * \brief Update HarfBuzz's idea of font metrics
+ * \param hb_font HarfBuzz font
+ * \param face associated FreeType font face
+ */
+static void update_hb_size(hb_font_t *hb_font, FT_Face face)
+{
+    hb_font_set_scale (hb_font,
+            ((uint64_t) face->size->metrics.x_scale * (uint64_t) face->units_per_EM) >> 16,
+            ((uint64_t) face->size->metrics.y_scale * (uint64_t) face->units_per_EM) >> 16);
+    hb_font_set_ppem (hb_font, face->size->metrics.x_ppem,
+            face->size->metrics.y_ppem);
+}
+
+
+/*
+ * Cached glyph metrics getters follow
+ *
+ * These functions replace HarfBuzz' standard FreeType font functions
+ * and provide cached access to essential glyph metrics. This usually
+ * speeds up shaping a lot. It also allows us to use custom load flags.
+ *
+ */
+
+GlyphMetricsHashValue *
+get_cached_metrics(struct ass_shaper_metrics_data *metrics, FT_Face face,
+                   hb_codepoint_t glyph)
+{
+    GlyphMetricsHashValue *val;
+
+    metrics->hash_key.glyph_index = glyph;
+    val = ass_cache_get(metrics->metrics_cache, &metrics->hash_key);
+
+    if (!val) {
+        int load_flags = FT_LOAD_DEFAULT | FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH
+            | FT_LOAD_IGNORE_TRANSFORM;
+        GlyphMetricsHashValue new_val;
+
+        if (FT_Load_Glyph(face, glyph, load_flags))
+            return NULL;
+
+        memcpy(&new_val.metrics, &face->glyph->metrics, sizeof(FT_Glyph_Metrics));
+        val = ass_cache_put(metrics->metrics_cache, &metrics->hash_key, &new_val);
+    }
+
+    return val;
+}
+
+static hb_bool_t
+get_glyph(hb_font_t *font, void *font_data, hb_codepoint_t unicode,
+          hb_codepoint_t variation, hb_codepoint_t *glyph, void *user_data)
+{
+    FT_Face face = font_data;
+
+    if (variation)
+        *glyph = FT_Face_GetCharVariantIndex(face, unicode, variation);
+    else
+        *glyph = FT_Get_Char_Index(face, unicode);
+
+    return *glyph != 0;
+}
+
+static hb_position_t
+cached_h_advance(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+                 void *user_data)
+{
+    FT_Face face = font_data;
+    struct ass_shaper_metrics_data *metrics_priv = user_data;
+    GlyphMetricsHashValue *metrics = get_cached_metrics(metrics_priv, face, glyph);
+
+    if (!metrics)
+        return 0;
+
+    if (metrics_priv->vertical && glyph > VERTICAL_LOWER_BOUND)
+        return metrics->metrics.vertAdvance;
+
+    return metrics->metrics.horiAdvance;
+}
+
+static hb_position_t
+cached_v_advance(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+                 void *user_data)
+{
+    FT_Face face = font_data;
+    struct ass_shaper_metrics_data *metrics_priv = user_data;
+    GlyphMetricsHashValue *metrics = get_cached_metrics(metrics_priv, face, glyph);
+
+    if (!metrics)
+        return 0;
+
+    return metrics->metrics.vertAdvance;
+
+}
+
+static hb_bool_t
+cached_h_origin(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+                hb_position_t *x, hb_position_t *y, void *user_data)
+{
+    return 1;
+}
+
+static hb_bool_t
+cached_v_origin(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+                hb_position_t *x, hb_position_t *y, void *user_data)
+{
+    FT_Face face = font_data;
+    struct ass_shaper_metrics_data *metrics_priv = user_data;
+    GlyphMetricsHashValue *metrics = get_cached_metrics(metrics_priv, face, glyph);
+
+    if (!metrics)
+        return 0;
+
+    *x = metrics->metrics.horiBearingX - metrics->metrics.vertBearingX;
+    *y = metrics->metrics.horiBearingY - (-metrics->metrics.vertBearingY);
+
+    return 1;
+}
+
+static hb_position_t
+get_h_kerning(hb_font_t *font, void *font_data, hb_codepoint_t first,
+                 hb_codepoint_t second, void *user_data)
+{
+    FT_Face face = font_data;
+    FT_Vector kern;
+
+    if (FT_Get_Kerning (face, first, second, FT_KERNING_DEFAULT, &kern))
+        return 0;
+
+    return kern.x;
+}
+
+static hb_position_t
+get_v_kerning(hb_font_t *font, void *font_data, hb_codepoint_t first,
+                 hb_codepoint_t second, void *user_data)
+{
+    return 0;
+}
+
+static hb_bool_t
+cached_extents(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+               hb_glyph_extents_t *extents, void *user_data)
+{
+    FT_Face face = font_data;
+    struct ass_shaper_metrics_data *metrics_priv = user_data;
+    GlyphMetricsHashValue *metrics = get_cached_metrics(metrics_priv, face, glyph);
+
+    if (!metrics)
+        return 0;
+
+    extents->x_bearing = metrics->metrics.horiBearingX;
+    extents->y_bearing = metrics->metrics.horiBearingY;
+    extents->width     = metrics->metrics.width;
+    extents->height    = metrics->metrics.height;
+
+    return 1;
+}
+
+static hb_bool_t
+get_contour_point(hb_font_t *font, void *font_data, hb_codepoint_t glyph,
+                     unsigned int point_index, hb_position_t *x,
+                     hb_position_t *y, void *user_data)
+{
+    FT_Face face = font_data;
+    int load_flags = FT_LOAD_DEFAULT | FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH
+        | FT_LOAD_IGNORE_TRANSFORM;
+
+    if (FT_Load_Glyph(face, glyph, load_flags))
+        return 0;
+
+    if (point_index >= (unsigned)face->glyph->outline.n_points)
+        return 0;
+
+    *x = face->glyph->outline.points[point_index].x;
+    *y = face->glyph->outline.points[point_index].y;
+
+    return 1;
+}
+
+/**
+ * \brief Retrieve HarfBuzz font from cache.
+ * Create it from FreeType font, if needed.
+ * \param info glyph cluster
+ * \return HarfBuzz font
+ */
+static hb_font_t *get_hb_font(ASS_Shaper *shaper, GlyphInfo *info)
+{
+    ASS_Font *font = info->font;
+    hb_font_t **hb_fonts;
+
+    if (!font->shaper_priv)
+        font->shaper_priv = calloc(sizeof(ASS_ShaperFontData), 1);
+
+
+    hb_fonts = font->shaper_priv->fonts;
+    if (!hb_fonts[info->face_index]) {
+        hb_fonts[info->face_index] =
+            hb_ft_font_create(font->faces[info->face_index], NULL);
+
+        // set up cached metrics access
+        font->shaper_priv->metrics_data[info->face_index] =
+            calloc(sizeof(struct ass_shaper_metrics_data), 1);
+        struct ass_shaper_metrics_data *metrics =
+            font->shaper_priv->metrics_data[info->face_index];
+        metrics->metrics_cache = shaper->metrics_cache;
+        metrics->vertical = info->font->desc.vertical;
+
+        hb_font_funcs_t *funcs = hb_font_funcs_create();
+        font->shaper_priv->font_funcs[info->face_index] = funcs;
+        hb_font_funcs_set_glyph_func(funcs, get_glyph,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_h_advance_func(funcs, cached_h_advance,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_v_advance_func(funcs, cached_v_advance,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_h_origin_func(funcs, cached_h_origin,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_v_origin_func(funcs, cached_v_origin,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_h_kerning_func(funcs, get_h_kerning,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_v_kerning_func(funcs, get_v_kerning,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_extents_func(funcs, cached_extents,
+                metrics, NULL);
+        hb_font_funcs_set_glyph_contour_point_func(funcs, get_contour_point,
+                metrics, NULL);
+        hb_font_set_funcs(hb_fonts[info->face_index], funcs,
+                font->faces[info->face_index], NULL);
+    }
+
+    ass_face_set_size(font->faces[info->face_index], info->font_size);
+    update_hb_size(hb_fonts[info->face_index], font->faces[info->face_index]);
+
+    // update hash key for cached metrics
+    struct ass_shaper_metrics_data *metrics =
+        font->shaper_priv->metrics_data[info->face_index];
+    metrics->hash_key.font = info->font;
+    metrics->hash_key.face_index = info->face_index;
+    metrics->hash_key.size = info->font_size;
+    metrics->hash_key.scale_x = double_to_d6(info->scale_x);
+    metrics->hash_key.scale_y = double_to_d6(info->scale_y);
+
+    return hb_fonts[info->face_index];
+}
+
+/**
+ * \brief Shape event text with HarfBuzz. Full OpenType shaping.
+ * \param glyphs glyph clusters
+ * \param len number of clusters
+ */
+static void shape_harfbuzz(ASS_Shaper *shaper, GlyphInfo *glyphs, size_t len)
+{
+    int i, j;
+    int run = 0;
+    struct {
+        int offset;
+        int end;
+        hb_buffer_t *buf;
+        hb_font_t *font;
+    } runs[MAX_RUNS];
+
+
+    for (i = 0; i < len && run < MAX_RUNS; i++, run++) {
+        // get length and level of the current run
+        int k = i;
+        int level = glyphs[i].shape_run_id;
+        int direction = shaper->emblevels[k] % 2;
+        while (i < (len - 1) && level == glyphs[i+1].shape_run_id)
+            i++;
+        runs[run].offset = k;
+        runs[run].end    = i;
+        runs[run].buf    = hb_buffer_create();
+        runs[run].font   = get_hb_font(shaper, glyphs + k);
+        set_run_features(shaper, glyphs + k);
+        hb_buffer_pre_allocate(runs[run].buf, i - k + 1);
+        hb_buffer_set_direction(runs[run].buf, direction ? HB_DIRECTION_RTL :
+                HB_DIRECTION_LTR);
+        hb_buffer_set_language(runs[run].buf, shaper->language);
+        hb_buffer_add_utf32(runs[run].buf, shaper->event_text + k, i - k + 1,
+                0, i - k + 1);
+        hb_shape(runs[run].font, runs[run].buf, shaper->features,
+                shaper->n_features);
+    }
+
+    // Initialize: skip all glyphs, this is undone later as needed
+    for (i = 0; i < len; i++)
+        glyphs[i].skip = 1;
+
+    // Update glyph indexes, positions and advances from the shaped runs
+    for (i = 0; i < run; i++) {
+        int num_glyphs = hb_buffer_get_length(runs[i].buf);
+        hb_glyph_info_t *glyph_info = hb_buffer_get_glyph_infos(runs[i].buf, NULL);
+        hb_glyph_position_t *pos    = hb_buffer_get_glyph_positions(runs[i].buf, NULL);
+
+        for (j = 0; j < num_glyphs; j++) {
+            int idx = glyph_info[j].cluster + runs[i].offset;
+            GlyphInfo *info = glyphs + idx;
+            GlyphInfo *root = info;
+
+            // if we have more than one glyph per cluster, allocate a new one
+            // and attach to the root glyph
+            if (info->skip == 0) {
+                while (info->next)
+                    info = info->next;
+                info->next = malloc(sizeof(GlyphInfo));
+                memcpy(info->next, info, sizeof(GlyphInfo));
+                info = info->next;
+                info->next = NULL;
+            }
+
+            // set position and advance
+            info->skip = 0;
+            info->glyph_index = glyph_info[j].codepoint;
+            info->offset.x    = pos[j].x_offset * info->scale_x;
+            info->offset.y    = -pos[j].y_offset * info->scale_y;
+            info->advance.x   = pos[j].x_advance * info->scale_x;
+            info->advance.y   = -pos[j].y_advance * info->scale_y;
+
+            // accumulate advance in the root glyph
+            root->cluster_advance.x += info->advance.x;
+            root->cluster_advance.y += info->advance.y;
+        }
+    }
+
+    // Free runs and associated data
+    for (i = 0; i < run; i++) {
+        hb_buffer_destroy(runs[i].buf);
+    }
+
+}
+#endif
+
+/**
+ * \brief Shape event text with FriBidi. Does mirroring and simple
+ * Arabic shaping.
+ * \param len number of clusters
+ */
+static void shape_fribidi(ASS_Shaper *shaper, GlyphInfo *glyphs, size_t len)
+{
+    int i;
+    FriBidiJoiningType *joins = calloc(sizeof(*joins), len);
+
+    // shape on codepoint level
+    fribidi_get_joining_types(shaper->event_text, len, joins);
+    fribidi_join_arabic(shaper->ctypes, len, shaper->emblevels, joins);
+    fribidi_shape(FRIBIDI_FLAGS_DEFAULT | FRIBIDI_FLAGS_ARABIC,
+            shaper->emblevels, len, joins, shaper->event_text);
+
+    // update indexes
+    for (i = 0; i < len; i++) {
+        GlyphInfo *info = glyphs + i;
+        FT_Face face = info->font->faces[info->face_index];
+        info->symbol = shaper->event_text[i];
+        info->glyph_index = FT_Get_Char_Index(face, shaper->event_text[i]);
+    }
+
+    free(joins);
+}
+
+/**
+ * \brief Toggle kerning for HarfBuzz shaping.
+ * NOTE: currently only works with OpenType fonts, the TrueType fallback *always*
+ * kerns. It's a bug in HarfBuzz.
+ */
+void ass_shaper_set_kerning(ASS_Shaper *shaper, int kern)
+{
+#ifdef CONFIG_HARFBUZZ
+    shaper->features[KERN].value = !!kern;
+#endif
+}
+
+/**
+ * \brief Find shape runs according to the event's selected fonts
+ */
+void ass_shaper_find_runs(ASS_Shaper *shaper, ASS_Renderer *render_priv,
+                          GlyphInfo *glyphs, size_t len)
+{
+    int i;
+    int shape_run = 0;
+
+    for (i = 0; i < len; i++) {
+        GlyphInfo *last = glyphs + i - 1;
+        GlyphInfo *info = glyphs + i;
+        // skip drawings
+        if (info->symbol == 0xfffc)
+            continue;
+        // set size and get glyph index
+        ass_font_get_index(render_priv->fontconfig_priv, info->font,
+                info->symbol, &info->face_index, &info->glyph_index);
+        // shape runs share the same font face and size
+        if (i > 0 && (last->font != info->font ||
+                    last->font_size != info->font_size ||
+                    last->face_index != info->face_index))
+            shape_run++;
+        info->shape_run_id = shape_run;
+    }
+
+}
+
+/**
+ * \brief Set base direction (paragraph direction) of the text.
+ * \param dir base direction
+ */
+void ass_shaper_set_base_direction(ASS_Shaper *shaper, FriBidiParType dir)
+{
+    shaper->base_direction = dir;
+}
+
+/**
+ * \brief Set language hint. Some languages have specific character variants,
+ * like Serbian Cyrillic.
+ * \param lang ISO 639-1 two-letter language code
+ */
+void ass_shaper_set_language(ASS_Shaper *shaper, const char *code)
+{
+#ifdef CONFIG_HARFBUZZ
+    shaper->language = hb_language_from_string(code, -1);
+#endif
+}
+
+/**
+ * Set shaping level. Essentially switches between FriBidi and HarfBuzz.
+ */
+void ass_shaper_set_level(ASS_Shaper *shaper, ASS_ShapingLevel level)
+{
+    shaper->shaping_level = level;
+}
+
+/**
+ * \brief Shape an event's text. Calculates directional runs and shapes them.
+ * \param text_info event's text
+ */
+void ass_shaper_shape(ASS_Shaper *shaper, TextInfo *text_info)
+{
+    int i, last_break;
+    FriBidiParType dir;
+    GlyphInfo *glyphs = text_info->glyphs;
+
+    check_allocations(shaper, text_info->length);
+
+    // Get bidi character types and embedding levels
+    last_break = 0;
+    for (i = 0; i < text_info->length; i++) {
+        shaper->event_text[i] = glyphs[i].symbol;
+        // embedding levels should be calculated paragraph by paragraph
+        if (glyphs[i].symbol == '\n' || i == text_info->length - 1) {
+            dir = shaper->base_direction;
+            fribidi_get_bidi_types(shaper->event_text + last_break,
+                    i - last_break + 1, shaper->ctypes + last_break);
+            fribidi_get_par_embedding_levels(shaper->ctypes + last_break,
+                    i - last_break + 1, &dir, shaper->emblevels + last_break);
+            last_break = i + 1;
+        }
+    }
+
+    // add embedding levels to shape runs for final runs
+    for (i = 0; i < text_info->length; i++) {
+        glyphs[i].shape_run_id += shaper->emblevels[i];
+    }
+
+#ifdef CONFIG_HARFBUZZ
+    switch (shaper->shaping_level) {
+    case ASS_SHAPING_SIMPLE:
+        shape_fribidi(shaper, glyphs, text_info->length);
+        break;
+    case ASS_SHAPING_COMPLEX:
+        shape_harfbuzz(shaper, glyphs, text_info->length);
+        break;
+    }
+#else
+        shape_fribidi(shaper, glyphs, text_info->length);
+#endif
+
+
+    // clean up
+    for (i = 0; i < text_info->length; i++) {
+        // Skip direction override control characters
+        // NOTE: Behdad said HarfBuzz is supposed to remove these, but this hasn't
+        // been implemented yet
+        if (glyphs[i].symbol <= 0x202F && glyphs[i].symbol >= 0x202a) {
+            glyphs[i].symbol = 0;
+            glyphs[i].skip++;
+        }
+    }
+}
+
+/**
+ * \brief Create a new shaper instance and preallocate data structures
+ * \param prealloc preallocation size
+ */
+ASS_Shaper *ass_shaper_new(size_t prealloc)
+{
+    ASS_Shaper *shaper = calloc(sizeof(*shaper), 1);
+
+    shaper->base_direction = FRIBIDI_PAR_ON;
+    check_allocations(shaper, prealloc);
+
+#ifdef CONFIG_HARFBUZZ
+    init_features(shaper);
+    shaper->metrics_cache = ass_glyph_metrics_cache_create();
+#endif
+
+    return shaper;
+}
+
+
+/**
+ * \brief clean up additional data temporarily needed for shaping and
+ * (e.g. additional glyphs allocated)
+ */
+void ass_shaper_cleanup(ASS_Shaper *shaper, TextInfo *text_info)
+{
+    int i;
+
+    for (i = 0; i < text_info->length; i++) {
+        GlyphInfo *info = text_info->glyphs + i;
+        info = info->next;
+        while (info) {
+            GlyphInfo *next = info->next;
+            free(info);
+            info = next;
+        }
+    }
+}
+
+/**
+ * \brief Calculate reorder map to render glyphs in visual order
+ */
+FriBidiStrIndex *ass_shaper_reorder(ASS_Shaper *shaper, TextInfo *text_info)
+{
+    int i;
+
+    // Initialize reorder map
+    for (i = 0; i < text_info->length; i++)
+        shaper->cmap[i] = i;
+
+    // Create reorder map line-by-line
+    for (i = 0; i < text_info->n_lines; i++) {
+        LineInfo *line = text_info->lines + i;
+        int level;
+        FriBidiParType dir = FRIBIDI_PAR_ON;
+
+        level = fribidi_reorder_line(0,
+                shaper->ctypes + line->offset, line->len, 0, dir,
+                shaper->emblevels + line->offset, NULL,
+                shaper->cmap + line->offset);
+    }
+
+    return shaper->cmap;
+}
+
+/**
+ * \brief Resolve a Windows font encoding number to a suitable
+ * base direction. 177 and 178 are Hebrew and Arabic respectively, and
+ * they map to RTL. 1 is autodetection and is mapped to just that.
+ * Everything else is mapped to LTR.
+ * \param enc Windows font encoding
+ */
+FriBidiParType resolve_base_direction(int enc)
+{
+    switch (enc) {
+        case 1:
+            return FRIBIDI_PAR_ON;
+        case 177:
+        case 178:
+            return FRIBIDI_PAR_RTL;
+        default:
+            return FRIBIDI_PAR_LTR;
+    }
+}

Added: trunk/libass/ass_shaper.h
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ trunk/libass/ass_shaper.h	Sun Dec  4 00:08:03 2011	(r34388)
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2011 Grigori Goronzy <greg at chown.ath.cx>
+ *
+ * This file is part of libass.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef LIBASS_SHAPER_H
+#define LIBASS_SHAPER_H
+
+#include "config.h"
+
+#include <fribidi/fribidi.h>
+#include "ass_render.h"
+
+void ass_shaper_info(ASS_Library *lib);
+ASS_Shaper *ass_shaper_new(size_t prealloc);
+void ass_shaper_free(ASS_Shaper *shaper);
+void ass_shaper_set_kerning(ASS_Shaper *shaper, int kern);
+void ass_shaper_find_runs(ASS_Shaper *shaper, ASS_Renderer *render_priv,
+                          GlyphInfo *glyphs, size_t len);
+void ass_shaper_set_base_direction(ASS_Shaper *shaper, FriBidiParType dir);
+void ass_shaper_set_language(ASS_Shaper *shaper, const char *code);
+void ass_shaper_set_level(ASS_Shaper *shaper, ASS_ShapingLevel level);
+void ass_shaper_shape(ASS_Shaper *shaper, TextInfo *text_info);
+void ass_shaper_cleanup(ASS_Shaper *shaper, TextInfo *text_info);
+FriBidiStrIndex *ass_shaper_reorder(ASS_Shaper *shaper, TextInfo *text_info);
+FriBidiParType resolve_base_direction(int font_encoding);
+
+void ass_shaper_font_data_free(ASS_ShaperFontData *priv);
+
+#endif


More information about the MPlayer-cvslog mailing list