1 /* 2 * Copyright © 2011 Google, Inc. 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 * 24 * Google Author(s): Behdad Esfahbod 25 */ 26 27 #include "hb-shaper-impl.hh" 28 29 30 /* 31 * shaper face data 32 */ 33 34 struct hb_fallback_face_data_t {}; 35 36 hb_fallback_face_data_t * 37 _hb_fallback_shaper_face_data_create (hb_face_t *face HB_UNUSED) 38 { 39 return (hb_fallback_face_data_t *) HB_SHAPER_DATA_SUCCEEDED; 40 } 41 42 void 43 _hb_fallback_shaper_face_data_destroy (hb_fallback_face_data_t *data HB_UNUSED) 44 { 45 } 46 47 48 /* 49 * shaper font data 50 */ 51 52 struct hb_fallback_font_data_t {}; 53 54 hb_fallback_font_data_t * 55 _hb_fallback_shaper_font_data_create (hb_font_t *font HB_UNUSED) 56 { 57 return (hb_fallback_font_data_t *) HB_SHAPER_DATA_SUCCEEDED; 58 } 59 60 void 61 _hb_fallback_shaper_font_data_destroy (hb_fallback_font_data_t *data HB_UNUSED) 62 { 63 } 64 65 66 /* 67 * shaper 68 */ 69 70 hb_bool_t 71 _hb_fallback_shape (hb_shape_plan_t *shape_plan HB_UNUSED, 72 hb_font_t *font, 73 hb_buffer_t *buffer, 74 const hb_feature_t *features HB_UNUSED, 75 unsigned int num_features HB_UNUSED) 76 { 77 /* TODO 78 * 79 * - Apply fallback kern. 80 * - Handle Variation Selectors? 81 * - Apply normalization? 82 * 83 * This will make the fallback shaper into a dumb "TrueType" 84 * shaper which many people unfortunately still request. 85 */ 86 87 hb_codepoint_t space; 88 bool has_space = (bool) font->get_nominal_glyph (' ', &space); 89 90 buffer->clear_positions (); 91 92 hb_direction_t direction = buffer->props.direction; 93 hb_unicode_funcs_t *unicode = buffer->unicode; 94 unsigned int count = buffer->len; 95 hb_glyph_info_t *info = buffer->info; 96 hb_glyph_position_t *pos = buffer->pos; 97 for (unsigned int i = 0; i < count; i++) 98 { 99 if (has_space && unicode->is_default_ignorable (info[i].codepoint)) { 100 info[i].codepoint = space; 101 pos[i].x_advance = 0; 102 pos[i].y_advance = 0; 103 continue; 104 } 105 (void) font->get_nominal_glyph (info[i].codepoint, &info[i].codepoint); 106 font->get_glyph_advance_for_direction (info[i].codepoint, 107 direction, 108 &pos[i].x_advance, 109 &pos[i].y_advance); 110 font->subtract_glyph_origin_for_direction (info[i].codepoint, 111 direction, 112 &pos[i].x_offset, 113 &pos[i].y_offset); 114 } 115 116 if (HB_DIRECTION_IS_BACKWARD (direction)) 117 hb_buffer_reverse (buffer); 118 119 buffer->safe_to_break_all (); 120 121 return true; 122 }