michael@0: /*
michael@0:  * Copyright © 2012  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 icu_le
michael@0: #define hb_icu_le_shaper_font_data_t PortableFontInstance
michael@0: #include "hb-shaper-impl-private.hh"
michael@0: 
michael@0: #include "hb-icu-le/PortableFontInstance.h"
michael@0: 
michael@0: #include "layout/loengine.h"
michael@0: #include "unicode/unistr.h"
michael@0: 
michael@0: #include "hb-icu.h"
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper face data
michael@0:  */
michael@0: 
michael@0: struct hb_icu_le_shaper_face_data_t {};
michael@0: 
michael@0: hb_icu_le_shaper_face_data_t *
michael@0: _hb_icu_le_shaper_face_data_create (hb_face_t *face HB_UNUSED)
michael@0: {
michael@0:   return (hb_icu_le_shaper_face_data_t *) HB_SHAPER_DATA_SUCCEEDED;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_icu_le_shaper_face_data_destroy (hb_icu_le_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: hb_icu_le_shaper_font_data_t *
michael@0: _hb_icu_le_shaper_font_data_create (hb_font_t *font)
michael@0: {
michael@0:   LEErrorCode status = LE_NO_ERROR;
michael@0:   hb_icu_le_shaper_font_data_t *data = new PortableFontInstance (font->face,
michael@0: 								 font->x_scale,
michael@0: 								 font->y_scale,
michael@0: 								 status);
michael@0:   if (status != LE_NO_ERROR) {
michael@0:     delete (data);
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   return data;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_icu_le_shaper_font_data_destroy (hb_icu_le_shaper_font_data_t *data)
michael@0: {
michael@0:   delete (data);
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * shaper shape_plan data
michael@0:  */
michael@0: 
michael@0: struct hb_icu_le_shaper_shape_plan_data_t {};
michael@0: 
michael@0: hb_icu_le_shaper_shape_plan_data_t *
michael@0: _hb_icu_le_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
michael@0: 					  const hb_feature_t *user_features,
michael@0: 					  unsigned int        num_user_features)
michael@0: {
michael@0:   return (hb_icu_le_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
michael@0: }
michael@0: 
michael@0: void
michael@0: _hb_icu_le_shaper_shape_plan_data_destroy (hb_icu_le_shaper_shape_plan_data_t *data)
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_icu_le_shape (hb_shape_plan_t    *shape_plan,
michael@0: 		  hb_font_t          *font,
michael@0: 		  hb_buffer_t        *buffer,
michael@0: 		  const hb_feature_t *features,
michael@0: 		  unsigned int        num_features)
michael@0: {
michael@0:   LEFontInstance *font_instance = HB_SHAPER_DATA_GET (font);
michael@0:   le_int32 script_code = hb_icu_script_from_script (shape_plan->props.script);
michael@0:   le_int32 language_code = -1 /* TODO */;
michael@0:   le_int32 typography_flags = 3; /* Needed for ligatures and kerning */
michael@0:   LEErrorCode status = LE_NO_ERROR;
michael@0:   le_engine *le = le_create ((const le_font *) font_instance,
michael@0: 			     script_code,
michael@0: 			     language_code,
michael@0: 			     typography_flags,
michael@0: 			     &status);
michael@0:   if (status != LE_NO_ERROR)
michael@0:   { le_close (le); return false; }
michael@0: 
michael@0: retry:
michael@0: 
michael@0:   unsigned int scratch_size;
michael@0:   char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
michael@0: 
michael@0: #define ALLOCATE_ARRAY(Type, name, len) \
michael@0:   Type *name = (Type *) scratch; \
michael@0:   scratch += (len) * sizeof ((name)[0]); \
michael@0:   scratch_size -= (len) * sizeof ((name)[0]);
michael@0: 
michael@0:   ALLOCATE_ARRAY (LEUnicode, chars, buffer->len);
michael@0:   ALLOCATE_ARRAY (unsigned int, clusters, buffer->len);
michael@0: 
michael@0:   /* XXX Use UTF-16 decoder! */
michael@0:   for (unsigned int i = 0; i < buffer->len; i++) {
michael@0:     chars[i] = buffer->info[i].codepoint;
michael@0:     clusters[i] = buffer->info[i].cluster;
michael@0:   }
michael@0: 
michael@0:   unsigned int glyph_count = le_layoutChars (le,
michael@0: 					     chars,
michael@0: 					     0,
michael@0: 					     buffer->len,
michael@0: 					     buffer->len,
michael@0: 					     HB_DIRECTION_IS_BACKWARD (buffer->props.direction),
michael@0: 					     0., 0.,
michael@0: 					     &status);
michael@0:   if (status != LE_NO_ERROR)
michael@0:   { le_close (le); return false; }
michael@0: 
michael@0:   unsigned int num_glyphs = scratch_size / (sizeof (LEGlyphID) +
michael@0: 					    sizeof (le_int32) +
michael@0: 					    sizeof (float) * 2);
michael@0: 
michael@0:   if (unlikely (glyph_count >= num_glyphs || glyph_count > buffer->allocated)) {
michael@0:     buffer->ensure (buffer->allocated * 2);
michael@0:     if (buffer->in_error)
michael@0:     { le_close (le); return false; }
michael@0:     goto retry;
michael@0:   }
michael@0: 
michael@0:   ALLOCATE_ARRAY (LEGlyphID, glyphs, glyph_count);
michael@0:   ALLOCATE_ARRAY (le_int32, indices, glyph_count);
michael@0:   ALLOCATE_ARRAY (float, positions, glyph_count * 2 + 2);
michael@0: 
michael@0:   le_getGlyphs (le, glyphs, &status);
michael@0:   le_getCharIndices (le, indices, &status);
michael@0:   le_getGlyphPositions (le, positions, &status);
michael@0: 
michael@0: #undef ALLOCATE_ARRAY
michael@0: 
michael@0:   /* Ok, we've got everything we need, now compose output buffer,
michael@0:    * very, *very*, carefully! */
michael@0: 
michael@0:   unsigned int j = 0;
michael@0:   hb_glyph_info_t *info = buffer->info;
michael@0:   for (unsigned int i = 0; i < glyph_count; i++)
michael@0:   {
michael@0:     if (glyphs[i] >= 0xFFFE)
michael@0: 	continue;
michael@0: 
michael@0:     info[j].codepoint = glyphs[i];
michael@0:     info[j].cluster = clusters[indices[i]];
michael@0: 
michael@0:     /* icu-le doesn't seem to have separate advance values. */
michael@0:     info[j].mask = positions[2 * i + 2] - positions[2 * i];
michael@0:     info[j].var1.u32 = 0;
michael@0:     info[j].var2.u32 = -positions[2 * i + 1];
michael@0: 
michael@0:     j++;
michael@0:   }
michael@0:   buffer->len = j;
michael@0: 
michael@0:   buffer->clear_positions ();
michael@0: 
michael@0:   for (unsigned int i = 0; i < buffer->len; i++) {
michael@0:     hb_glyph_info_t *info = &buffer->info[i];
michael@0:     hb_glyph_position_t *pos = &buffer->pos[i];
michael@0: 
michael@0:     /* TODO vertical */
michael@0:     pos->x_advance = info->mask;
michael@0:     pos->x_offset = info->var1.u32;
michael@0:     pos->y_offset = info->var2.u32;
michael@0:   }
michael@0: 
michael@0:   le_close (le);
michael@0:   return true;
michael@0: }