vcl/source/font/FeatureCollector.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include <font/FeatureCollector.hxx>
  11 #include <font/OpenTypeFeatureDefinitonList.hxx>
  12
  13 #include <hb-ot.h>
  14 #include <hb-graphite2.h>
  15
  16 namespace vcl
  17 {
  18 namespace font
  19 {
  20 bool FeatureCollector::collectGraphite()
  21 {
  22     gr_face* grFace = hb_graphite2_face_get_gr_face(m_pHbFace);
  23
  24     if (grFace == nullptr)
  25         return false;
  26
  27     gr_uint16 nUILanguage = gr_uint16(m_eLanguageType);
  28
  29     gr_uint16 nNumberOfFeatures = gr_face_n_fref(grFace);
  30     gr_feature_val* pfeatureValues
  31         = gr_face_featureval_for_lang(grFace, 0); // shame we don't know which lang
  32
  33     for (gr_uint16 i = 0; i < nNumberOfFeatures; ++i)
  34     {
  35         const gr_feature_ref* pFeatureRef = gr_face_fref(grFace, i);
  36         gr_uint32 nFeatureCode = gr_fref_id(pFeatureRef);
  37
  38         if (nFeatureCode == 0) // illegal feature code - skip
  39             continue;
  40
  41         gr_uint16 nValue = gr_fref_feature_value(pFeatureRef, pfeatureValues);
  42         gr_uint32 nLabelLength = 0;
  43         void* pLabel = gr_fref_label(pFeatureRef, &nUILanguage, gr_utf8, &nLabelLength);
  44         OUString sLabel(OUString::createFromAscii(static_cast<char*>(pLabel)));
  45         gr_label_destroy(pLabel);
  46
  47         std::vector<vcl::font::FeatureParameter> aParameters;
  48         gr_uint16 nNumberOfValues = gr_fref_n_values(pFeatureRef);
  49
  50         if (nNumberOfValues > 0)
  51         {
  52             for (gr_uint16 j = 0; j < nNumberOfValues; ++j)
  53             {
  54                 gr_uint32 nValueLabelLength = 0;
  55                 void* pValueLabel = gr_fref_value_label(pFeatureRef, j, &nUILanguage, gr_utf8,
  56                                                         &nValueLabelLength);
  57                 OUString sValueLabel(OUString::createFromAscii(static_cast<char*>(pValueLabel)));
  58                 gr_uint16 nParamValue = gr_fref_value(pFeatureRef, j);
  59                 aParameters.emplace_back(sal_uInt32(nParamValue), sValueLabel);
  60                 gr_label_destroy(pValueLabel);
  61             }
  62
  63             auto eFeatureParameterType = vcl::font::FeatureParameterType::ENUM;
  64
  65             // Check if the parameters are boolean
  66             if (aParameters.size() == 2
  67                 && (aParameters[0].getDescription() == "True"
  68                     || aParameters[0].getDescription() == "False"))
  69             {
  70                 eFeatureParameterType = vcl::font::FeatureParameterType::BOOL;
  71                 aParameters.clear();
  72             }
  73
  74             m_rFontFeatures.emplace_back(
  75                 FeatureID{ nFeatureCode, HB_OT_TAG_DEFAULT_SCRIPT, HB_OT_TAG_DEFAULT_LANGUAGE },
  76                 vcl::font::FeatureType::Graphite);
  77             vcl::font::Feature& rFeature = m_rFontFeatures.back();
  78             rFeature.m_aDefinition = vcl::font::FeatureDefinition(
  79                 nFeatureCode, sLabel, eFeatureParameterType, aParameters, sal_uInt32(nValue));
  80         }
  81     }
  82     return true;
  83 }
  84
  85 void FeatureCollector::collectForLanguage(hb_tag_t aTableTag, sal_uInt32 nScript,
  86                                           hb_tag_t aScriptTag, sal_uInt32 nLanguage,
  87                                           hb_tag_t aLanguageTag)
  88 {
  89     unsigned int nFeatureCount = hb_ot_layout_language_get_feature_tags(
  90         m_pHbFace, aTableTag, nScript, nLanguage, 0, nullptr, nullptr);
  91     std::vector<hb_tag_t> aFeatureTags(nFeatureCount);
  92     hb_ot_layout_language_get_feature_tags(m_pHbFace, aTableTag, nScript, nLanguage, 0,
  93                                            &nFeatureCount, aFeatureTags.data());
  94     aFeatureTags.resize(nFeatureCount);
  95
  96     for (hb_tag_t aFeatureTag : aFeatureTags)
  97     {
  98         if (OpenTypeFeatureDefinitonList::get().isRequired(aFeatureTag))
  99             continue;
 100
 101         m_rFontFeatures.emplace_back();
 102         vcl::font::Feature& rFeature = m_rFontFeatures.back();
 103         rFeature.m_aID = { aFeatureTag, aScriptTag, aLanguageTag };
 104
 105         FeatureDefinition aDefinition
 106             = OpenTypeFeatureDefinitonList::get().getDefinition(aFeatureTag);
 107         if (aDefinition)
 108         {
 109             rFeature.m_aDefinition = aDefinition;
 110         }
 111     }
 112 }
 113
 114 void FeatureCollector::collectForScript(hb_tag_t aTableTag, sal_uInt32 nScript, hb_tag_t aScriptTag)
 115 {
 116     collectForLanguage(aTableTag, nScript, aScriptTag, HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX,
 117                        HB_OT_TAG_DEFAULT_LANGUAGE);
 118
 119     unsigned int nLanguageCount
 120         = hb_ot_layout_script_get_language_tags(m_pHbFace, aTableTag, nScript, 0, nullptr, nullptr);
 121     std::vector<hb_tag_t> aLanguageTags(nLanguageCount);
 122     hb_ot_layout_script_get_language_tags(m_pHbFace, aTableTag, nScript, 0, &nLanguageCount,
 123                                           aLanguageTags.data());
 124     aLanguageTags.resize(nLanguageCount);
 125     for (sal_uInt32 nLanguage = 0; nLanguage < sal_uInt32(nLanguageCount); ++nLanguage)
 126         collectForLanguage(aTableTag, nScript, aScriptTag, nLanguage, aLanguageTags[nLanguage]);
 127 }
 128
 129 void FeatureCollector::collectForTable(hb_tag_t aTableTag)
 130 {
 131     unsigned int nScriptCount
 132         = hb_ot_layout_table_get_script_tags(m_pHbFace, aTableTag, 0, nullptr, nullptr);
 133     std::vector<hb_tag_t> aScriptTags(nScriptCount);
 134     hb_ot_layout_table_get_script_tags(m_pHbFace, aTableTag, 0, &nScriptCount, aScriptTags.data());
 135     aScriptTags.resize(nScriptCount);
 136
 137     for (sal_uInt32 nScript = 0; nScript < sal_uInt32(nScriptCount); ++nScript)
 138         collectForScript(aTableTag, nScript, aScriptTags[nScript]);
 139 }
 140
 141 bool FeatureCollector::collect()
 142 {
 143     gr_face* grFace = hb_graphite2_face_get_gr_face(m_pHbFace);
 144
 145     if (grFace)
 146     {
 147         return collectGraphite();
 148     }
 149     else
 150     {
 151         collectForTable(HB_OT_TAG_GSUB); // substitution
 152         collectForTable(HB_OT_TAG_GPOS); // positioning
 153         return true;
 154     }
 155 }
 156
 157 } // end namespace font
 158 } // end namespace vcl
 159
 160 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */