michael@0: /*
michael@0:  * Copyright © 2011  Google, Inc.
michael@0:  *
michael@0:  *  This is part of HarfBuzz, a text shaping library.
michael@0:  *
michael@0:  * Permission is hereby granted, without written agreement and without
michael@0:  * license or royalty fees, to use, copy, modify, and distribute this
michael@0:  * software and its documentation for any purpose, provided that the
michael@0:  * above copyright notice and the following two paragraphs appear in
michael@0:  * all copies of this software.
michael@0:  *
michael@0:  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
michael@0:  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
michael@0:  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
michael@0:  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
michael@0:  * DAMAGE.
michael@0:  *
michael@0:  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
michael@0:  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
michael@0:  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
michael@0:  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
michael@0:  *
michael@0:  * Google Author(s): Behdad Esfahbod
michael@0:  */
michael@0: 
michael@0: #define HB_SHAPER fallback
michael@0: #include "hb-shaper-impl-private.hh"
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper face data
michael@0:  */
michael@0: 
michael@0: struct hb_fallback_shaper_face_data_t {};
michael@0: 
michael@0: hb_fallback_shaper_face_data_t *
michael@0: _hb_fallback_shaper_face_data_create (hb_face_t *face HB_UNUSED)
michael@0: {
michael@0:   return (hb_fallback_shaper_face_data_t *) HB_SHAPER_DATA_SUCCEEDED;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_fallback_shaper_face_data_destroy (hb_fallback_shaper_face_data_t *data HB_UNUSED)
michael@0: {
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper font data
michael@0:  */
michael@0: 
michael@0: struct hb_fallback_shaper_font_data_t {};
michael@0: 
michael@0: hb_fallback_shaper_font_data_t *
michael@0: _hb_fallback_shaper_font_data_create (hb_font_t *font HB_UNUSED)
michael@0: {
michael@0:   return (hb_fallback_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_fallback_shaper_font_data_destroy (hb_fallback_shaper_font_data_t *data HB_UNUSED)
michael@0: {
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper shape_plan data
michael@0:  */
michael@0: 
michael@0: struct hb_fallback_shaper_shape_plan_data_t {};
michael@0: 
michael@0: hb_fallback_shaper_shape_plan_data_t *
michael@0: _hb_fallback_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
michael@0: 					    const hb_feature_t *user_features HB_UNUSED,
michael@0: 					    unsigned int        num_user_features HB_UNUSED)
michael@0: {
michael@0:   return (hb_fallback_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_fallback_shaper_shape_plan_data_destroy (hb_fallback_shaper_shape_plan_data_t *data HB_UNUSED)
michael@0: {
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper
michael@0:  */
michael@0: 
michael@0: hb_bool_t
michael@0: _hb_fallback_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
michael@0: 		    hb_font_t          *font,
michael@0: 		    hb_buffer_t        *buffer,
michael@0: 		    const hb_feature_t *features HB_UNUSED,
michael@0: 		    unsigned int        num_features HB_UNUSED)
michael@0: {
michael@0:   /* TODO
michael@0:    *
michael@0:    * - Apply fallback kern.
michael@0:    * - Handle Variation Selectors?
michael@0:    * - Apply normalization?
michael@0:    *
michael@0:    * This will make the fallback shaper into a dumb "TrueType"
michael@0:    * shaper which many people unfortunately still request.
michael@0:    */
michael@0: 
michael@0:   bool has_space;
michael@0:   hb_codepoint_t space;
michael@0:   has_space = font->get_glyph (' ', 0, &space);
michael@0: 
michael@0:   buffer->clear_positions ();
michael@0: 
michael@0:   unsigned int count = buffer->len;
michael@0: 
michael@0:   for (unsigned int i = 0; i < count; i++)
michael@0:   {
michael@0:     if (has_space && buffer->unicode->is_default_ignorable (buffer->info[i].codepoint)) {
michael@0:       buffer->info[i].codepoint = space;
michael@0:       buffer->pos[i].x_advance = 0;
michael@0:       buffer->pos[i].y_advance = 0;
michael@0:       continue;
michael@0:     }
michael@0:     font->get_glyph (buffer->info[i].codepoint, 0, &buffer->info[i].codepoint);
michael@0:     font->get_glyph_advance_for_direction (buffer->info[i].codepoint,
michael@0: 					   buffer->props.direction,
michael@0: 					   &buffer->pos[i].x_advance,
michael@0: 					   &buffer->pos[i].y_advance);
michael@0:     font->subtract_glyph_origin_for_direction (buffer->info[i].codepoint,
michael@0: 					       buffer->props.direction,
michael@0: 					       &buffer->pos[i].x_offset,
michael@0: 					       &buffer->pos[i].y_offset);
michael@0:   }
michael@0: 
michael@0:   if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
michael@0:     hb_buffer_reverse (buffer);
michael@0: 
michael@0:   return true;
michael@0: }