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