| /* Pango |
| * pango-ot-buffer.c: Buffer of glyphs for shaping/positioning |
| * |
| * Copyright (C) 2004 Red Hat Software |
| * |
| * 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 "pango-ot-private.h" |
| |
| #define PANGO_SCALE_26_6 (PANGO_SCALE / (1<<6)) |
| #define PANGO_UNITS_26_6(d) (PANGO_SCALE_26_6 * (d)) |
| |
| PangoOTBuffer * |
| pango_ot_buffer_new (PangoFcFont *font) |
| { |
| /* We lock the font here immediately for the silly reason |
| * of getting the FT_Memory; otherwise we'd have to |
| * add a new operation to PangoFcFontmap; callers will |
| * probably already have the font locked, however, |
| * so there is little performance penalty. |
| */ |
| PangoOTBuffer *buffer = g_new (PangoOTBuffer, 1); |
| FT_Face face = pango_fc_font_lock_face (font); |
| |
| if (otl_buffer_new (face->memory, &buffer->buffer) != FT_Err_Ok) |
| g_error ("Allocation of OTLBuffer failed"); |
| |
| buffer->font = g_object_ref (font); |
| buffer->applied_gpos = FALSE; |
| buffer->rtl = FALSE; |
| buffer->zero_width_marks = FALSE; |
| |
| pango_fc_font_unlock_face (font); |
| |
| return buffer; |
| } |
| |
| void |
| pango_ot_buffer_destroy (PangoOTBuffer *buffer) |
| { |
| otl_buffer_free (buffer->buffer); |
| g_object_unref (buffer->font); |
| g_free (buffer); |
| } |
| |
| void |
| pango_ot_buffer_clear (PangoOTBuffer *buffer) |
| { |
| otl_buffer_clear (buffer->buffer); |
| buffer->applied_gpos = FALSE; |
| } |
| |
| void |
| pango_ot_buffer_add_glyph (PangoOTBuffer *buffer, |
| guint glyph_index, |
| guint properties, |
| guint cluster) |
| { |
| otl_buffer_add_glyph (buffer->buffer, |
| glyph_index, properties, cluster); |
| |
| } |
| |
| void |
| pango_ot_buffer_set_rtl (PangoOTBuffer *buffer, |
| gboolean rtl) |
| { |
| rtl = rtl != FALSE; |
| buffer->rtl = rtl; |
| } |
| |
| /** |
| * pango_ot_buffer_set_zero_width_marks: |
| * @buffer: a #PangoOTBuffer |
| * @zero_width_marks: %TRUE if characters with a mark class should |
| * be forced to zero width. |
| * |
| * Sets whether characters with a mark class should be forced to zero width. |
| * This setting is needed for proper positioning of Arabic accents, |
| * but will produce incorrect results with standard OpenType indic |
| * fonts. |
| **/ |
| void |
| pango_ot_buffer_set_zero_width_marks (PangoOTBuffer *buffer, |
| gboolean zero_width_marks) |
| { |
| buffer->zero_width_marks = zero_width_marks != FALSE; |
| } |
| |
| void |
| pango_ot_buffer_get_glyphs (PangoOTBuffer *buffer, |
| PangoOTGlyph **glyphs, |
| int *n_glyphs) |
| { |
| if (glyphs) |
| *glyphs = (PangoOTGlyph *)buffer->buffer->in_string; |
| |
| if (n_glyphs) |
| *n_glyphs = buffer->buffer->in_length; |
| } |
| |
| static void |
| swap_range (PangoGlyphString *glyphs, int start, int end) |
| { |
| int i, j; |
| |
| for (i = start, j = end - 1; i < j; i++, j--) |
| { |
| PangoGlyphInfo glyph_info; |
| gint log_cluster; |
| |
| glyph_info = glyphs->glyphs[i]; |
| glyphs->glyphs[i] = glyphs->glyphs[j]; |
| glyphs->glyphs[j] = glyph_info; |
| |
| log_cluster = glyphs->log_clusters[i]; |
| glyphs->log_clusters[i] = glyphs->log_clusters[j]; |
| glyphs->log_clusters[j] = log_cluster; |
| } |
| } |
| |
| static void |
| apply_gpos_ltr (PangoGlyphString *glyphs, |
| OTL_Position positions) |
| { |
| int i; |
| |
| for (i = 0; i < glyphs->num_glyphs; i++) |
| { |
| FT_Pos x_pos = positions[i].x_pos; |
| FT_Pos y_pos = positions[i].y_pos; |
| int back = i; |
| int j; |
| |
| while (positions[back].back != 0) |
| { |
| back -= positions[back].back; |
| x_pos += positions[back].x_pos; |
| y_pos += positions[back].y_pos; |
| } |
| |
| for (j = back; j < i; j++) |
| glyphs->glyphs[i].geometry.x_offset -= glyphs->glyphs[j].geometry.width; |
| |
| glyphs->glyphs[i].geometry.x_offset += PANGO_UNITS_26_6(x_pos); |
| glyphs->glyphs[i].geometry.y_offset -= PANGO_UNITS_26_6(y_pos); |
| |
| if (positions[i].new_advance) |
| glyphs->glyphs[i].geometry.width = PANGO_UNITS_26_6(positions[i].x_advance); |
| else |
| glyphs->glyphs[i].geometry.width += PANGO_UNITS_26_6(positions[i].x_advance); |
| } |
| } |
| |
| static void |
| apply_gpos_rtl (PangoGlyphString *glyphs, |
| OTL_Position positions) |
| { |
| int i; |
| |
| for (i = 0; i < glyphs->num_glyphs; i++) |
| { |
| int i_rev = glyphs->num_glyphs - i - 1; |
| int back_rev = i_rev; |
| int back; |
| FT_Pos x_pos = positions[i_rev].x_pos; |
| FT_Pos y_pos = positions[i_rev].y_pos; |
| int j; |
| |
| while (positions[back_rev].back != 0) |
| { |
| back_rev -= positions[back_rev].back; |
| x_pos += positions[back_rev].x_pos; |
| y_pos += positions[back_rev].y_pos; |
| } |
| |
| back = glyphs->num_glyphs - back_rev - 1; |
| |
| for (j = i; j < back; j++) |
| glyphs->glyphs[i].geometry.x_offset += glyphs->glyphs[j].geometry.width; |
| |
| glyphs->glyphs[i].geometry.x_offset += PANGO_UNITS_26_6(x_pos); |
| glyphs->glyphs[i].geometry.y_offset -= PANGO_UNITS_26_6(y_pos); |
| |
| if (positions[i_rev].new_advance) |
| glyphs->glyphs[i].geometry.width = PANGO_UNITS_26_6(positions[i_rev].x_advance); |
| else |
| glyphs->glyphs[i].geometry.width += PANGO_UNITS_26_6(positions[i_rev].x_advance); |
| } |
| } |
| |
| void |
| pango_ot_buffer_output (PangoOTBuffer *buffer, |
| PangoGlyphString *glyphs) |
| { |
| FT_Face face; |
| PangoOTInfo *info; |
| TTO_GDEF gdef = NULL; |
| int i; |
| int last_cluster; |
| |
| face = pango_fc_font_lock_face (buffer->font); |
| g_assert (face); |
| |
| /* Copy glyphs into output glyph string */ |
| pango_glyph_string_set_size (glyphs, buffer->buffer->in_length); |
| |
| last_cluster = -1; |
| for (i = 0; i < buffer->buffer->in_length; i++) |
| { |
| OTL_GlyphItem item = &buffer->buffer->in_string[i]; |
| |
| glyphs->glyphs[i].glyph = item->gindex; |
| |
| glyphs->log_clusters[i] = item->cluster; |
| if (glyphs->log_clusters[i] != last_cluster) |
| glyphs->glyphs[i].attr.is_cluster_start = 1; |
| else |
| glyphs->glyphs[i].attr.is_cluster_start = 0; |
| |
| last_cluster = glyphs->log_clusters[i]; |
| } |
| |
| info = pango_ot_info_get (face); |
| gdef = pango_ot_info_get_gdef (info); |
| |
| /* Apply default positioning */ |
| for (i = 0; i < glyphs->num_glyphs; i++) |
| { |
| if (glyphs->glyphs[i].glyph) |
| { |
| PangoRectangle logical_rect; |
| |
| FT_UShort property; |
| |
| if (buffer->zero_width_marks && |
| gdef && |
| TT_GDEF_Get_Glyph_Property (gdef, glyphs->glyphs[i].glyph, &property) == FT_Err_Ok && |
| (property == TTO_MARK || (property & IGNORE_SPECIAL_MARKS) != 0)) |
| { |
| glyphs->glyphs[i].geometry.width = 0; |
| } |
| else |
| { |
| pango_font_get_glyph_extents ((PangoFont *)buffer->font, glyphs->glyphs[i].glyph, NULL, &logical_rect); |
| glyphs->glyphs[i].geometry.width = logical_rect.width; |
| } |
| } |
| else |
| glyphs->glyphs[i].geometry.width = 0; |
| |
| glyphs->glyphs[i].geometry.x_offset = 0; |
| glyphs->glyphs[i].geometry.y_offset = 0; |
| } |
| |
| if (buffer->rtl) |
| { |
| /* Swap all glyphs */ |
| swap_range (glyphs, 0, glyphs->num_glyphs); |
| } |
| |
| if (buffer->applied_gpos) |
| { |
| if (buffer->rtl) |
| apply_gpos_rtl (glyphs, buffer->buffer->positions); |
| else |
| apply_gpos_ltr (glyphs, buffer->buffer->positions); |
| } |
| |
| pango_fc_font_unlock_face (buffer->font); |
| } |