dlls/dwrite/shape.c

   1 /*
   2  *    Glyph shaping support
   3  *
   4  * Copyright 2010 Aric Stewart for CodeWeavers
   5  * Copyright 2014 Nikolay Sivov for CodeWeavers
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #define COBJMACROS
  23
  24 #include "dwrite.h"
  25 #include "dwrite_private.h"
  26
  27 WINE_DEFAULT_DEBUG_CHANNEL(dwrite);
  28
  29 struct scriptshaping_cache
  30 {
  31     IDWriteFontFace *fontface;
  32     UINT32 language_tag;
  33 };
  34
  35 HRESULT create_scriptshaping_cache(IDWriteFontFace *fontface, const WCHAR *locale, struct scriptshaping_cache **cache)
  36 {
  37     struct scriptshaping_cache *ret;
  38
  39     ret = heap_alloc(sizeof(*ret));
  40     if (!ret)
  41         return E_OUTOFMEMORY;
  42
  43     ret->fontface = fontface;
  44     IDWriteFontFace_AddRef(fontface);
  45
  46     ret->language_tag = DWRITE_MAKE_OPENTYPE_TAG('d','f','l','t');
  47     if (locale) {
  48         WCHAR tag[5];
  49         if (GetLocaleInfoEx(locale, LOCALE_SOPENTYPELANGUAGETAG, tag, sizeof(tag)/sizeof(WCHAR)))
  50             ret->language_tag = DWRITE_MAKE_OPENTYPE_TAG(tag[0],tag[1],tag[2],tag[3]);
  51     }
  52
  53     *cache = ret;
  54
  55     return S_OK;
  56 }
  57
  58 void release_scriptshaping_cache(struct scriptshaping_cache *cache)
  59 {
  60     if (!cache)
  61         return;
  62     IDWriteFontFace_Release(cache->fontface);
  63     heap_free(cache);
  64 }
  65
  66 static void shape_update_clusters_from_glyphprop(UINT32 glyphcount, UINT32 text_len, UINT16 *clustermap, DWRITE_SHAPING_GLYPH_PROPERTIES *glyph_props)
  67 {
  68     UINT32 i;
  69
  70     for (i = 0; i < glyphcount; i++) {
  71         if (!glyph_props[i].isClusterStart) {
  72             UINT32 j;
  73
  74             for (j = 0; j < text_len; j++) {
  75                 if (clustermap[j] == i) {
  76                     int k = j;
  77                     while (k >= 0 && k < text_len && !glyph_props[clustermap[k]].isClusterStart)
  78                         k--;
  79
  80                     if (k >= 0 && k < text_len && glyph_props[clustermap[k]].isClusterStart)
  81                         clustermap[j] = clustermap[k];
  82                 }
  83             }
  84         }
  85     }
  86 }
  87
  88 static int compare_clustersearch(const void *a, const void* b)
  89 {
  90     UINT16 target = *(UINT16*)a;
  91     UINT16 index = *(UINT16*)b;
  92     int ret = 0;
  93
  94     if (target > index)
  95         ret = 1;
  96     else if (target < index)
  97         ret = -1;
  98
  99     return ret;
 100 }
 101
 102 /* Maps given glyph position in glyph indices array to text index this glyph represents.
 103    Lowest possible index is returned.
 104
 105    clustermap [I] Text index to index in glyph indices array map
 106    len        [I] Clustermap size
 107    target     [I] Index in glyph indices array to map
 108  */
 109 static INT32 map_glyph_to_text_pos(const UINT16 *clustermap, UINT32 len, UINT16 target)
 110 {
 111     UINT16 *ptr;
 112     INT32 k;
 113
 114     ptr = bsearch(&target, clustermap, len, sizeof(UINT16), compare_clustersearch);
 115     if (!ptr)
 116         return -1;
 117
 118     /* get to the beginning */
 119     for (k = (ptr - clustermap) - 1; k >= 0 && clustermap[k] == target; k--)
 120         ;
 121     k++;
 122
 123     return k;
 124 }
 125
 126 static HRESULT default_set_text_glyphs_props(struct scriptshaping_cache *cache, const WCHAR *text, UINT32 len, UINT16 *clustermap, UINT16 *glyph_indices,
 127                                      UINT32 glyphcount, DWRITE_SHAPING_TEXT_PROPERTIES *text_props, DWRITE_SHAPING_GLYPH_PROPERTIES *glyph_props)
 128 {
 129     UINT32 i;
 130
 131     for (i = 0; i < glyphcount; i++) {
 132         UINT32 char_index[20];
 133         UINT32 char_count = 0;
 134         INT32 k;
 135
 136         k = map_glyph_to_text_pos(clustermap, len, i);
 137         if (k >= 0) {
 138             for (; k < len && clustermap[k] == i; k++)
 139                 char_index[char_count++] = k;
 140         }
 141
 142         if (char_count == 0)
 143             continue;
 144
 145         if (char_count == 1 && isspaceW(text[char_index[0]])) {
 146             glyph_props[i].justification = SCRIPT_JUSTIFY_BLANK;
 147             text_props[char_index[0]].isShapedAlone = text[char_index[0]] == ' ';
 148         }
 149         else
 150             glyph_props[i].justification = SCRIPT_JUSTIFY_CHARACTER;
 151     }
 152
 153     /* FIXME: update properties using GDEF table */
 154     shape_update_clusters_from_glyphprop(glyphcount, len, clustermap, glyph_props);
 155
 156     return S_OK;
 157 }
 158
 159 static HRESULT latn_set_text_glyphs_props(struct scriptshaping_cache *cache, const WCHAR *text, UINT32 len, UINT16 *clustermap, UINT16 *glyph_indices,
 160                                      UINT32 glyphcount, DWRITE_SHAPING_TEXT_PROPERTIES *text_props, DWRITE_SHAPING_GLYPH_PROPERTIES *glyph_props)
 161 {
 162     HRESULT hr;
 163     UINT32 i;
 164
 165     hr = default_set_text_glyphs_props(cache, text, len, clustermap, glyph_indices, glyphcount, text_props, glyph_props);
 166
 167     for (i = 0; i < glyphcount; i++)
 168         if (glyph_props[i].isZeroWidthSpace)
 169             glyph_props[i].justification = SCRIPT_JUSTIFY_NONE;
 170
 171     return hr;
 172 }
 173
 174 const struct scriptshaping_ops latn_shaping_ops =
 175 {
 176     NULL,
 177     latn_set_text_glyphs_props
 178 };
 179
 180 const struct scriptshaping_ops default_shaping_ops =
 181 {
 182     NULL,
 183     default_set_text_glyphs_props
 184 };