/* Pango * pangofc-shape.c: Basic shaper for FreeType-based backends * * Copyright (C) 2000, 2007, 2009 Red Hat Software * Authors: * Owen Taylor * Behdad Esfahbod * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include "config.h" #include #include #include "pangohb-private.h" #include "pango-impl-utils.h" #include /* cache a single hb_buffer_t */ static hb_buffer_t *cached_buffer = NULL; /* MT-safe */ G_LOCK_DEFINE_STATIC (cached_buffer); static hb_buffer_t * acquire_buffer (gboolean *free_buffer) { hb_buffer_t *buffer; if (G_LIKELY (G_TRYLOCK (cached_buffer))) { if (G_UNLIKELY (!cached_buffer)) cached_buffer = hb_buffer_create (); buffer = cached_buffer; *free_buffer = FALSE; } else { buffer = hb_buffer_create (); *free_buffer = TRUE; } return buffer; } static void release_buffer (hb_buffer_t *buffer, gboolean free_buffer) { if (G_LIKELY (!free_buffer)) { hb_buffer_reset (buffer); G_UNLOCK (cached_buffer); } else hb_buffer_destroy (buffer); } static void apply_extra_attributes (GSList *attrs, hb_feature_t *features, guint length, guint *num_features) { GSList *l; for (l = attrs; l && *num_features < length; l = l->next) { PangoAttribute *attr = l->data; if (attr->klass->type == PANGO_ATTR_FONT_FEATURES) { PangoAttrFontFeatures *fattr = (PangoAttrFontFeatures *) attr; const gchar *feat; const gchar *end; int len; feat = fattr->features; while (feat != NULL && *num_features < length) { end = strchr (feat, ','); if (end) len = end - feat; else len = -1; if (hb_feature_from_string (feat, len, &features[*num_features])) { features[*num_features].start = attr->start_index; features[*num_features].end = attr->end_index; (*num_features)++; } if (end == NULL) break; feat = end + 1; } } } /* Turn off ligatures when letterspacing */ for (l = attrs; l && *num_features < length; l = l->next) { PangoAttribute *attr = l->data; if (attr->klass->type == PANGO_ATTR_LETTER_SPACING) { hb_tag_t tags[] = { HB_TAG('l','i','g','a'), HB_TAG('c','l','i','g'), HB_TAG('d','l','i','g'), }; int i; for (i = 0; i < G_N_ELEMENTS (tags); i++) { features[*num_features].tag = tags[i]; features[*num_features].value = 0; features[*num_features].start = attr->start_index; features[*num_features].end = attr->end_index; (*num_features)++; } } } } typedef struct { PangoFont *font; hb_font_t *parent; PangoShowFlags show_flags; } PangoHbShapeContext; static hb_bool_t pango_hb_font_get_nominal_glyph (hb_font_t *font, void *font_data, hb_codepoint_t unicode, hb_codepoint_t *glyph, void *user_data G_GNUC_UNUSED) { PangoHbShapeContext *context = (PangoHbShapeContext *) font_data; if ((context->show_flags & PANGO_SHOW_IGNORABLES) != 0) { if (pango_get_ignorable (unicode)) { *glyph = PANGO_GET_UNKNOWN_GLYPH (unicode); return TRUE; } } if ((context->show_flags & PANGO_SHOW_SPACES) != 0) { if (g_unichar_type (unicode) == G_UNICODE_SPACE_SEPARATOR) { /* Replace 0x20 by visible space, since we * don't draw a hex box for 0x20 */ if (unicode == 0x20) *glyph = PANGO_GET_UNKNOWN_GLYPH (0x2423); else *glyph = PANGO_GET_UNKNOWN_GLYPH (unicode); return TRUE; } } if ((context->show_flags & PANGO_SHOW_LINE_BREAKS) != 0) { if (unicode == 0x2028) { /* Always mark LS as unknown. If it ends up * at the line end, PangoLayout takes care of * hiding them, and if they end up in the middle * of a line, we are in single paragraph mode * and want to show the LS */ *glyph = PANGO_GET_UNKNOWN_GLYPH (unicode); return TRUE; } } if (hb_font_get_nominal_glyph (context->parent, unicode, glyph)) return TRUE; *glyph = PANGO_GET_UNKNOWN_GLYPH (unicode); /* We draw our own invalid-Unicode shape, so prevent HarfBuzz * from using REPLACEMENT CHARACTER. */ if (unicode > 0x10FFFF) return TRUE; return FALSE; } static hb_position_t pango_hb_font_get_glyph_h_advance (hb_font_t *font, void *font_data, hb_codepoint_t glyph, void *user_data G_GNUC_UNUSED) { PangoHbShapeContext *context = (PangoHbShapeContext *) font_data; if (glyph & PANGO_GLYPH_UNKNOWN_FLAG) { PangoRectangle logical; pango_font_get_glyph_extents (context->font, glyph, NULL, &logical); return logical.width; } return hb_font_get_glyph_h_advance (context->parent, glyph); } static hb_position_t pango_hb_font_get_glyph_v_advance (hb_font_t *font, void *font_data, hb_codepoint_t glyph, void *user_data G_GNUC_UNUSED) { PangoHbShapeContext *context = (PangoHbShapeContext *) font_data; if (glyph & PANGO_GLYPH_UNKNOWN_FLAG) { PangoRectangle logical; pango_font_get_glyph_extents (context->font, glyph, NULL, &logical); return logical.height; } return hb_font_get_glyph_v_advance (context->parent, glyph); } static hb_bool_t pango_hb_font_get_glyph_extents (hb_font_t *font, void *font_data, hb_codepoint_t glyph, hb_glyph_extents_t *extents, void *user_data G_GNUC_UNUSED) { PangoHbShapeContext *context = (PangoHbShapeContext *) font_data; if (glyph & PANGO_GLYPH_UNKNOWN_FLAG) { PangoRectangle ink; pango_font_get_glyph_extents (context->font, glyph, &ink, NULL); extents->x_bearing = ink.x; extents->y_bearing = ink.y; extents->width = ink.width; extents->height = ink.height; return TRUE; } return hb_font_get_glyph_extents (context->parent, glyph, extents); } static hb_font_t * pango_font_get_hb_font_for_context (PangoFont *font, PangoHbShapeContext *context) { hb_font_t *hb_font; static hb_font_funcs_t *funcs; hb_font = pango_font_get_hb_font (font); if (G_UNLIKELY (!funcs)) { funcs = hb_font_funcs_create (); hb_font_funcs_set_nominal_glyph_func (funcs, pango_hb_font_get_nominal_glyph, NULL, NULL); hb_font_funcs_set_glyph_h_advance_func (funcs, pango_hb_font_get_glyph_h_advance, NULL, NULL); hb_font_funcs_set_glyph_v_advance_func (funcs, pango_hb_font_get_glyph_v_advance, NULL, NULL); hb_font_funcs_set_glyph_extents_func (funcs, pango_hb_font_get_glyph_extents, NULL, NULL); hb_font_funcs_make_immutable (funcs); } context->font = font; context->parent = hb_font; hb_font = hb_font_create_sub_font (hb_font); hb_font_set_funcs (hb_font, funcs, context, NULL); return hb_font; } static PangoShowFlags find_show_flags (const PangoAnalysis *analysis) { GSList *l; PangoShowFlags flags = 0; for (l = analysis->extra_attrs; l; l = l->next) { PangoAttribute *attr = l->data; if (attr->klass->type == PANGO_ATTR_SHOW) flags |= ((PangoAttrInt*)attr)->value; } return flags; } void pango_hb_shape (PangoFont *font, const char *item_text, unsigned int item_length, const PangoAnalysis *analysis, PangoGlyphString *glyphs, const char *paragraph_text, unsigned int paragraph_length) { PangoHbShapeContext context = { 0, }; hb_buffer_flags_t hb_buffer_flags; hb_font_t *hb_font; hb_buffer_t *hb_buffer; hb_direction_t hb_direction; gboolean free_buffer; hb_glyph_info_t *hb_glyph; hb_glyph_position_t *hb_position; int last_cluster; guint i, num_glyphs; unsigned int item_offset = item_text - paragraph_text; hb_feature_t features[32]; unsigned int num_features = 0; PangoGlyphInfo *infos; g_return_if_fail (font != NULL); g_return_if_fail (analysis != NULL); context.show_flags = find_show_flags (analysis); hb_font = pango_font_get_hb_font_for_context (font, &context); hb_buffer = acquire_buffer (&free_buffer); hb_direction = PANGO_GRAVITY_IS_VERTICAL (analysis->gravity) ? HB_DIRECTION_TTB : HB_DIRECTION_LTR; if (analysis->level % 2) hb_direction = HB_DIRECTION_REVERSE (hb_direction); if (PANGO_GRAVITY_IS_IMPROPER (analysis->gravity)) hb_direction = HB_DIRECTION_REVERSE (hb_direction); hb_buffer_flags = HB_BUFFER_FLAG_BOT | HB_BUFFER_FLAG_EOT; if (context.show_flags & PANGO_SHOW_IGNORABLES) hb_buffer_flags |= HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES; /* setup buffer */ hb_buffer_set_direction (hb_buffer, hb_direction); hb_buffer_set_script (hb_buffer, hb_glib_script_to_script (analysis->script)); hb_buffer_set_language (hb_buffer, hb_language_from_string (pango_language_to_string (analysis->language), -1)); hb_buffer_set_cluster_level (hb_buffer, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS); hb_buffer_set_flags (hb_buffer, hb_buffer_flags); hb_buffer_set_invisible_glyph (hb_buffer, PANGO_GLYPH_EMPTY); hb_buffer_add_utf8 (hb_buffer, paragraph_text, paragraph_length, item_offset, item_length); if (analysis->flags & PANGO_ANALYSIS_FLAG_NEED_HYPHEN) { /* Insert either a Unicode or ASCII hyphen. We may * want to look for script-specific hyphens here. */ const char *p = paragraph_text + item_offset + item_length; int last_char_len = p - g_utf8_prev_char (p); hb_codepoint_t glyph; if (hb_font_get_nominal_glyph (hb_font, 0x2010, &glyph)) hb_buffer_add (hb_buffer, 0x2010, item_offset + item_length - last_char_len); else if (hb_font_get_nominal_glyph (hb_font, '-', &glyph)) hb_buffer_add (hb_buffer, '-', item_offset + item_length - last_char_len); } pango_font_get_features (font, features, G_N_ELEMENTS (features), &num_features); apply_extra_attributes (analysis->extra_attrs, features, G_N_ELEMENTS (features), &num_features); hb_shape (hb_font, hb_buffer, features, num_features); if (PANGO_GRAVITY_IS_IMPROPER (analysis->gravity)) hb_buffer_reverse (hb_buffer); /* buffer output */ num_glyphs = hb_buffer_get_length (hb_buffer); hb_glyph = hb_buffer_get_glyph_infos (hb_buffer, NULL); pango_glyph_string_set_size (glyphs, num_glyphs); infos = glyphs->glyphs; last_cluster = -1; for (i = 0; i < num_glyphs; i++) { infos[i].glyph = hb_glyph->codepoint; glyphs->log_clusters[i] = hb_glyph->cluster - item_offset; infos[i].attr.is_cluster_start = glyphs->log_clusters[i] != last_cluster; hb_glyph++; last_cluster = glyphs->log_clusters[i]; } hb_position = hb_buffer_get_glyph_positions (hb_buffer, NULL); if (PANGO_GRAVITY_IS_VERTICAL (analysis->gravity)) for (i = 0; i < num_glyphs; i++) { /* 90 degrees rotation counter-clockwise. */ infos[i].geometry.width = - hb_position->y_advance; infos[i].geometry.x_offset = - hb_position->y_offset; infos[i].geometry.y_offset = - hb_position->x_offset; hb_position++; } else /* horizontal */ for (i = 0; i < num_glyphs; i++) { infos[i].geometry.width = hb_position->x_advance; infos[i].geometry.x_offset = hb_position->x_offset; infos[i].geometry.y_offset = - hb_position->y_offset; hb_position++; } release_buffer (hb_buffer, free_buffer); hb_font_destroy (hb_font); }