src/declarative/items/qsgtextnode.cpp

   1 /****************************************************************************
   2 **
   3 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
   4 ** All rights reserved.
   5 ** Contact: Nokia Corporation (qt-info@nokia.com)
   6 **
   7 ** This file is part of the QtDeclarative module of the Qt Toolkit.
   8 **
   9 ** $QT_BEGIN_LICENSE:LGPL$
  10 ** No Commercial Usage
  11 ** This file contains pre-release code and may not be distributed.
  12 ** You may use this file in accordance with the terms and conditions
  13 ** contained in the Technology Preview License Agreement accompanying
  14 ** this package.
  15 **
  16 ** GNU Lesser General Public License Usage
  17 ** Alternatively, this file may be used under the terms of the GNU Lesser
  18 ** General Public License version 2.1 as published by the Free Software
  19 ** Foundation and appearing in the file LICENSE.LGPL included in the
  20 ** packaging of this file.  Please review the following information to
  21 ** ensure the GNU Lesser General Public License version 2.1 requirements
  22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
  23 **
  24 ** In addition, as a special exception, Nokia gives you certain additional
  25 ** rights.  These rights are described in the Nokia Qt LGPL Exception
  26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
  27 **
  28 ** If you have questions regarding the use of this file, please contact
  29 ** Nokia at qt-info@nokia.com.
  30 **
  31 **
  32 **
  33 **
  34 **
  35 **
  36 **
  37 **
  38 ** $QT_END_LICENSE$
  39 **
  40 ****************************************************************************/
  41
  42 #include "qsgtextnode_p.h"
  43 #include "qsgsimplerectnode.h"
  44 #include <private/qsgadaptationlayer_p.h>
  45 #include <private/qsgdistancefieldglyphcache_p.h>
  46 #include <private/qsgdistancefieldglyphnode_p.h>
  47
  48 #include <private/qsgcontext_p.h>
  49
  50 #include <qmath.h>
  51 #include <qtextdocument.h>
  52 #include <qtextlayout.h>
  53 #include <qabstracttextdocumentlayout.h>
  54 #include <qxmlstream.h>
  55 #include <qrawfont.h>
  56 #include <private/qdeclarativestyledtext_p.h>
  57 #include <private/qfont_p.h>
  58 #include <private/qfontengine_p.h>
  59 #include <private/qrawfont_p.h>
  60
  61 QT_BEGIN_NAMESPACE
  62
  63 /*!
  64   Creates an empty QSGTextNode
  65 */
  66 QSGTextNode::QSGTextNode(QSGContext *context)
  67 : m_context(context)
  68 {
  69 #if defined(QML_RUNTIME_TESTING)
  70     description = QLatin1String("text");
  71 #endif
  72 }
  73
  74 QSGTextNode::~QSGTextNode()
  75 {
  76 }
  77
  78 #if 0
  79 void QSGTextNode::setColor(const QColor &color)
  80 {
  81     if (m_usePixmapCache) {
  82         setUpdateFlag(UpdateNodes);
  83     } else {
  84         for (int i=0; i<childCount(); ++i) {
  85             QSGNode *childNode = childAtIndex(i);
  86             if (childNode->subType() == GlyphNodeSubType) {
  87                 QSGGlyphNode *glyphNode = static_cast<QSGGlyphNode *>(childNode);
  88                 if (glyphNode->color() == m_color)
  89                     glyphNode->setColor(color);
  90             } else if (childNode->subType() == SolidRectNodeSubType) {
  91                 QSGSimpleRectNode *solidRectNode = static_cast<QSGSimpleRectNode *>(childNode);
  92                 if (solidRectNode->color() == m_color)
  93                     solidRectNode->setColor(color);
  94             }
  95         }
  96     }
  97     m_color = color;
  98 }
  99
 100 void QSGTextNode::setStyleColor(const QColor &styleColor)
 101 {
 102     if (m_textStyle != QSGTextNode::NormalTextStyle) {
 103         if (m_usePixmapCache) {
 104             setUpdateFlag(UpdateNodes);
 105         } else {
 106             for (int i=0; i<childCount(); ++i) {
 107                 QSGNode *childNode = childAtIndex(i);
 108                 if (childNode->subType() == GlyphNodeSubType) {
 109                     QSGGlyphNode *glyphNode = static_cast<QSGGlyphNode *>(childNode);
 110                     if (glyphNode->color() == m_styleColor)
 111                         glyphNode->setColor(styleColor);
 112                 } else if (childNode->subType() == SolidRectNodeSubType) {
 113                     QSGSimpleRectNode *solidRectNode = static_cast<QSGSimpleRectNode *>(childNode);
 114                     if (solidRectNode->color() == m_styleColor)
 115                         solidRectNode->setColor(styleColor);
 116                 }
 117             }
 118         }
 119     }
 120     m_styleColor = styleColor;
 121 }
 122 #endif
 123
 124 void QSGTextNode::addTextDecorations(const QPointF &position, const QRawFont &font, const QColor &color,
 125                                      qreal width, bool hasOverline, bool hasStrikeOut, bool hasUnderline)
 126 {
 127     Q_ASSERT(font.isValid());
 128     QRawFontPrivate *dptrFont = QRawFontPrivate::get(font);
 129     QFontEngine *fontEngine = dptrFont->fontEngine;
 130
 131     qreal lineThickness = fontEngine->lineThickness().toReal();
 132
 133     QRectF line(position.x(), position.y() - lineThickness / 2.0, width, lineThickness);
 134
 135     if (hasUnderline) {
 136         int underlinePosition = fontEngine->underlinePosition().ceil().toInt();
 137         QRectF underline(line);
 138         underline.translate(0.0, underlinePosition);
 139         appendChildNode(new QSGSimpleRectNode(underline, color));
 140     }
 141
 142     qreal ascent = font.ascent();
 143     if (hasOverline) {
 144         QRectF overline(line);
 145         overline.translate(0.0, -ascent);
 146         appendChildNode(new QSGSimpleRectNode(overline, color));
 147     }
 148
 149     if (hasStrikeOut) {
 150         QRectF strikeOut(line);
 151         strikeOut.translate(0.0, ascent / -3.0);
 152         appendChildNode(new QSGSimpleRectNode(strikeOut, color));
 153     }
 154 }
 155
 156 QSGGlyphNode *QSGTextNode::addGlyphs(const QPointF &position, const QGlyphRun &glyphs, const QColor &color,
 157                                            QSGText::TextStyle style, const QColor &styleColor)
 158 {
 159     QSGGlyphNode *node = m_context->createGlyphNode();
 160     if (QSGDistanceFieldGlyphCache::distanceFieldEnabled()) {
 161         QSGDistanceFieldGlyphNode *dfNode = static_cast<QSGDistanceFieldGlyphNode *>(node);
 162         dfNode->setStyle(style);
 163         dfNode->setStyleColor(styleColor);
 164     }
 165     node->setGlyphs(position, glyphs);
 166     node->setColor(color);
 167
 168     appendChildNode(node);
 169
 170     if (glyphs.overline() || glyphs.strikeOut() || glyphs.underline()) {
 171         QPointF baseLine = node->baseLine();
 172         qreal width = node->boundingRect().width();
 173         addTextDecorations(baseLine, glyphs.rawFont(), color, width,
 174                            glyphs.overline(), glyphs.strikeOut(), glyphs.underline());
 175     }
 176
 177     return node;
 178 }
 179
 180 void QSGTextNode::addTextDocument(const QPointF &position, QTextDocument *textDocument, const QColor &color,
 181                                   QSGText::TextStyle style, const QColor &styleColor)
 182 {
 183     Q_UNUSED(position)
 184     QTextFrame *textFrame = textDocument->rootFrame();
 185     QPointF p = textDocument->documentLayout()->frameBoundingRect(textFrame).topLeft();
 186
 187     QTextFrame::iterator it = textFrame->begin();
 188     while (!it.atEnd()) {
 189         addTextBlock(p, textDocument, it.currentBlock(), color, style, styleColor);
 190         ++it;
 191     }
 192 }
 193
 194 void QSGTextNode::addTextLayout(const QPointF &position, QTextLayout *textLayout, const QColor &color,
 195                                 QSGText::TextStyle style, const QColor &styleColor)
 196 {
 197     QList<QGlyphRun> glyphsList(textLayout->glyphRuns());
 198     for (int i=0; i<glyphsList.size(); ++i) {
 199         QGlyphRun glyphs = glyphsList.at(i);
 200         QRawFont font = glyphs.rawFont();
 201         addGlyphs(position + QPointF(0, font.ascent()), glyphs, color, style, styleColor);
 202     }
 203 }
 204
 205
 206 /*!
 207   Returns true if \a text contains any HTML tags, attributes or CSS properties which are unrelated
 208    to text, fonts or text layout. Otherwise the function returns false. If the return value is
 209   false, \a text is considered to be easily representable in the scenegraph. If it returns true,
 210   then the text should be prerendered into a pixmap before it's displayed on screen.
 211 */
 212 bool QSGTextNode::isComplexRichText(QTextDocument *doc)
 213 {
 214     if (doc == 0)
 215         return false;
 216
 217     static QSet<QString> supportedTags;
 218     if (supportedTags.isEmpty()) {
 219         supportedTags.insert(QLatin1String("i"));
 220         supportedTags.insert(QLatin1String("b"));
 221         supportedTags.insert(QLatin1String("u"));
 222         supportedTags.insert(QLatin1String("div"));
 223         supportedTags.insert(QLatin1String("big"));
 224         supportedTags.insert(QLatin1String("blockquote"));
 225         supportedTags.insert(QLatin1String("body"));
 226         supportedTags.insert(QLatin1String("br"));
 227         supportedTags.insert(QLatin1String("center"));
 228         supportedTags.insert(QLatin1String("cite"));
 229         supportedTags.insert(QLatin1String("code"));
 230         supportedTags.insert(QLatin1String("tt"));
 231         supportedTags.insert(QLatin1String("dd"));
 232         supportedTags.insert(QLatin1String("dfn"));
 233         supportedTags.insert(QLatin1String("em"));
 234         supportedTags.insert(QLatin1String("font"));
 235         supportedTags.insert(QLatin1String("h1"));
 236         supportedTags.insert(QLatin1String("h2"));
 237         supportedTags.insert(QLatin1String("h3"));
 238         supportedTags.insert(QLatin1String("h4"));
 239         supportedTags.insert(QLatin1String("h5"));
 240         supportedTags.insert(QLatin1String("h6"));
 241         supportedTags.insert(QLatin1String("head"));
 242         supportedTags.insert(QLatin1String("html"));
 243         supportedTags.insert(QLatin1String("meta"));
 244         supportedTags.insert(QLatin1String("nobr"));
 245         supportedTags.insert(QLatin1String("p"));
 246         supportedTags.insert(QLatin1String("pre"));
 247         supportedTags.insert(QLatin1String("qt"));
 248         supportedTags.insert(QLatin1String("s"));
 249         supportedTags.insert(QLatin1String("samp"));
 250         supportedTags.insert(QLatin1String("small"));
 251         supportedTags.insert(QLatin1String("span"));
 252         supportedTags.insert(QLatin1String("strong"));
 253         supportedTags.insert(QLatin1String("sub"));
 254         supportedTags.insert(QLatin1String("sup"));
 255         supportedTags.insert(QLatin1String("title"));
 256         supportedTags.insert(QLatin1String("var"));
 257         supportedTags.insert(QLatin1String("style"));
 258     }
 259
 260     static QSet<QCss::Property> supportedCssProperties;
 261     if (supportedCssProperties.isEmpty()) {
 262         supportedCssProperties.insert(QCss::Color);
 263         supportedCssProperties.insert(QCss::Float);
 264         supportedCssProperties.insert(QCss::Font);
 265         supportedCssProperties.insert(QCss::FontFamily);
 266         supportedCssProperties.insert(QCss::FontSize);
 267         supportedCssProperties.insert(QCss::FontStyle);
 268         supportedCssProperties.insert(QCss::FontWeight);
 269         supportedCssProperties.insert(QCss::Margin);
 270         supportedCssProperties.insert(QCss::MarginBottom);
 271         supportedCssProperties.insert(QCss::MarginLeft);
 272         supportedCssProperties.insert(QCss::MarginRight);
 273         supportedCssProperties.insert(QCss::MarginTop);
 274         supportedCssProperties.insert(QCss::TextDecoration);
 275         supportedCssProperties.insert(QCss::TextIndent);
 276         supportedCssProperties.insert(QCss::TextUnderlineStyle);
 277         supportedCssProperties.insert(QCss::VerticalAlignment);
 278         supportedCssProperties.insert(QCss::Whitespace);
 279         supportedCssProperties.insert(QCss::Padding);
 280         supportedCssProperties.insert(QCss::PaddingLeft);
 281         supportedCssProperties.insert(QCss::PaddingRight);
 282         supportedCssProperties.insert(QCss::PaddingTop);
 283         supportedCssProperties.insert(QCss::PaddingBottom);
 284         supportedCssProperties.insert(QCss::PageBreakBefore);
 285         supportedCssProperties.insert(QCss::PageBreakAfter);
 286         supportedCssProperties.insert(QCss::Width);
 287         supportedCssProperties.insert(QCss::Height);
 288         supportedCssProperties.insert(QCss::MinimumWidth);
 289         supportedCssProperties.insert(QCss::MinimumHeight);
 290         supportedCssProperties.insert(QCss::MaximumWidth);
 291         supportedCssProperties.insert(QCss::MaximumHeight);
 292         supportedCssProperties.insert(QCss::Left);
 293         supportedCssProperties.insert(QCss::Right);
 294         supportedCssProperties.insert(QCss::Top);
 295         supportedCssProperties.insert(QCss::Bottom);
 296         supportedCssProperties.insert(QCss::Position);
 297         supportedCssProperties.insert(QCss::TextAlignment);
 298         supportedCssProperties.insert(QCss::FontVariant);
 299     }
 300
 301     QXmlStreamReader reader(doc->toHtml("utf-8"));
 302     while (!reader.atEnd()) {
 303         reader.readNext();
 304
 305         if (reader.isStartElement()) {
 306             if (!supportedTags.contains(reader.name().toString().toLower()))
 307                 return true;
 308
 309             QXmlStreamAttributes attributes = reader.attributes();
 310             if (attributes.hasAttribute(QLatin1String("bgcolor")))
 311                 return true;
 312             if (attributes.hasAttribute(QLatin1String("style"))) {
 313                 QCss::StyleSheet styleSheet;
 314                 QCss::Parser(attributes.value(QLatin1String("style")).toString()).parse(&styleSheet);
 315
 316                 QVector<QCss::Declaration> decls;
 317                 for (int i=0; i<styleSheet.pageRules.size(); ++i)
 318                     decls += styleSheet.pageRules.at(i).declarations;
 319
 320                 QVector<QCss::StyleRule> styleRules =
 321                         styleSheet.styleRules
 322                         + styleSheet.idIndex.values().toVector()
 323                         + styleSheet.nameIndex.values().toVector();
 324                 for (int i=0; i<styleSheet.mediaRules.size(); ++i)
 325                     styleRules += styleSheet.mediaRules.at(i).styleRules;
 326
 327                 for (int i=0; i<styleRules.size(); ++i)
 328                     decls += styleRules.at(i).declarations;
 329
 330                 for (int i=0; i<decls.size(); ++i) {
 331                     if (!supportedCssProperties.contains(decls.at(i).d->propertyId))
 332                         return true;
 333                 }
 334
 335             }
 336         }
 337     }
 338
 339     return reader.hasError();
 340 }
 341
 342 void QSGTextNode::addTextBlock(const QPointF &position, QTextDocument *textDocument, const QTextBlock &block,
 343                                const QColor &overrideColor, QSGText::TextStyle style, const QColor &styleColor)
 344 {
 345     if (!block.isValid())
 346         return;
 347
 348     QPointF blockPosition = textDocument->documentLayout()->blockBoundingRect(block).topLeft();
 349
 350     QTextBlock::iterator it = block.begin();
 351     while (!it.atEnd()) {
 352         QTextFragment fragment = it.fragment();
 353         if (!fragment.text().isEmpty()) {
 354             QTextCharFormat charFormat = fragment.charFormat();
 355             QColor color = overrideColor.isValid()
 356                     ? overrideColor
 357                     : charFormat.foreground().color();
 358
 359             QList<QGlyphRun> glyphsList = fragment.glyphRuns();
 360             for (int i=0; i<glyphsList.size(); ++i) {
 361                 QGlyphRun glyphs = glyphsList.at(i);
 362                 QRawFont font = glyphs.rawFont();
 363                 addGlyphs(position + blockPosition + QPointF(0, font.ascent()),
 364                           glyphs, color, style, styleColor);
 365             }
 366         }
 367
 368         ++it;
 369     }
 370 }
 371
 372 void QSGTextNode::deleteContent()
 373 {
 374     while (childCount() > 0)
 375         delete childAtIndex(0);
 376 }
 377
 378 #if 0
 379 void QSGTextNode::updateNodes()
 380 {
 381     return;
 382     deleteContent();
 383     if (m_text.isEmpty())
 384         return;
 385
 386     if (m_usePixmapCache) {
 387         // ### gunnar: port properly
 388 //        QPixmap pixmap = generatedPixmap();
 389 //        if (pixmap.isNull())
 390 //            return;
 391
 392 //        QSGImageNode *pixmapNode = m_context->createImageNode();
 393 //        pixmapNode->setRect(pixmap.rect());
 394 //        pixmapNode->setSourceRect(pixmap.rect());
 395 //        pixmapNode->setOpacity(m_opacity);
 396 //        pixmapNode->setClampToEdge(true);
 397 //        pixmapNode->setLinearFiltering(m_linearFiltering);
 398
 399 //        appendChildNode(pixmapNode);
 400     } else {
 401         if (m_text.isEmpty())
 402             return;
 403
 404         // Implement styling by drawing text several times at slight shifts. shiftForStyle
 405         // contains the sequence of shifted positions at which to draw the text. All except
 406         // the last will be drawn with styleColor.
 407         QList<QPointF> shiftForStyle;
 408         switch (m_textStyle) {
 409         case OutlineTextStyle:
 410             // ### Should be made faster by implementing outline material
 411             shiftForStyle << QPointF(-1, 0);
 412             shiftForStyle << QPointF(0, -1);
 413             shiftForStyle << QPointF(1, 0);
 414             shiftForStyle << QPointF(0, 1);
 415             break;
 416         case SunkenTextStyle:
 417             shiftForStyle << QPointF(0, -1);
 418             break;
 419         case RaisedTextStyle:
 420             shiftForStyle << QPointF(0, 1);
 421             break;
 422         default:
 423             break;
 424         }
 425
 426         shiftForStyle << QPointF(0, 0); // Regular position
 427         while (!shiftForStyle.isEmpty()) {
 428             QPointF shift = shiftForStyle.takeFirst();
 429
 430             // Use styleColor for all but last shift
 431             if (m_richText) {
 432                 QColor overrideColor = shiftForStyle.isEmpty() ? QColor() : m_styleColor;
 433
 434                 QTextFrame *textFrame = m_textDocument->rootFrame();
 435                 QPointF p = m_textDocument->documentLayout()->frameBoundingRect(textFrame).topLeft();
 436
 437                 QTextFrame::iterator it = textFrame->begin();
 438                 while (!it.atEnd()) {
 439                     addTextBlock(shift + p, it.currentBlock(), overrideColor);
 440                     ++it;
 441                 }
 442             } else {
 443                 addTextLayout(shift, m_textLayout, shiftForStyle.isEmpty()
 444                                                    ? m_color
 445                                                    : m_styleColor);
 446             }
 447         }
 448     }
 449 }
 450 #endif
 451
 452 QT_END_NAMESPACE