X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Ffrontends%2Fqt4%2FGuiFontMetrics.cpp;h=33df3cf1267a68c5f7a3e51084e150d65b6abc9c;hb=1f10969bb5c5f36017bf5ba8671381b09945cf57;hp=6e40804ddd519f4cccc3109357267a17f4c3e244;hpb=1c2cf3567cdaa4cbb257535e52fabab3273aa2d5;p=lyx.git diff --git a/src/frontends/qt4/GuiFontMetrics.cpp b/src/frontends/qt4/GuiFontMetrics.cpp index 6e40804ddd..33df3cf126 100644 --- a/src/frontends/qt4/GuiFontMetrics.cpp +++ b/src/frontends/qt4/GuiFontMetrics.cpp @@ -15,31 +15,86 @@ #include "qt_helpers.h" -#include "Language.h" #include "Dimension.h" +#include "Language.h" +#include "LyXRC.h" + +#include "insets/Inset.h" + +#include "support/convert.h" +#include "support/lassert.h" + +#define DISABLE_PMPROF +#include "support/pmprof.h" + +#include -#include "support/unicode.h" +using namespace std; +using namespace lyx::support; + +namespace std { + +/* + * Argument-dependent lookup implies that this function shall be + * declared in the namespace of its argument. But this is std + * namespace, since lyx::docstring is just std::basic_string. + */ +uint qHash(lyx::docstring const & s) +{ + return qHash(QByteArray(reinterpret_cast(s.data()), + s.size() * sizeof(lyx::docstring::value_type))); +} -using std::string; +} namespace lyx { namespace frontend { -// Caution: When using ucs4_to_qchar() in these methods, this is no -// real conversion but a simple cast in reality. This is the reason -// why this works well for symbol fonts used in mathed too, even though -// these are not real ucs4 characters. These are codepoints in the -// modern fonts used, nothing unicode related. -// See comment in QLPainter::text() for more explanation. -GuiFontMetrics::GuiFontMetrics(QFont const & font) -: metrics_(font), smallcaps_metrics_(font), smallcaps_shape_(false) +/* + * Limit (strwidth|breakat)_cache_ size to 512kB of string data. + * Limit qtextlayout_cache_ size to 500 elements (we do not know the + * size of the QTextLayout objects anyway). + * Note that all these numbers are arbitrary. + * Also, setting size to 0 is tantamount to disabling the cache. + */ +int cache_metrics_width_size = 1 << 19; +int cache_metrics_breakat_size = 1 << 19; +// Qt 5.x already has its own caching of QTextLayout objects +#if (QT_VERSION < 0x050000) +int cache_metrics_qtextlayout_size = 500; +#else +int cache_metrics_qtextlayout_size = 0; +#endif + + +namespace { +/** + * Convert a UCS4 character into a QChar. + * This is a hack (it does only make sense for the common part of the UCS4 + * and UTF16 encodings) and should not be used. + * This does only exist because of performance reasons (a real conversion + * using iconv is too slow on windows). + * + * This is no real conversion but a simple cast in reality. This is the reason + * why this works well for symbol fonts used in mathed too, even though + * these are not real ucs4 characters. These are codepoints in the + * computer modern fonts used, nothing unicode related. + * See comment in GuiPainter::text() for more explanation. + **/ +inline QChar const ucs4_to_qchar(char_type const ucs4) { + LATTEST(is_utf16(ucs4)); + return QChar(static_cast(ucs4)); } +} // anon namespace -GuiFontMetrics::GuiFontMetrics(QFont const & font, QFont const & smallcaps_font) -: metrics_(font), smallcaps_metrics_(smallcaps_font), smallcaps_shape_(true) +GuiFontMetrics::GuiFontMetrics(QFont const & font) + : font_(font), metrics_(font, 0), + strwidth_cache_(cache_metrics_width_size), + breakat_cache_(cache_metrics_breakat_size), + qtextlayout_cache_(cache_metrics_qtextlayout_size) { } @@ -58,66 +113,98 @@ int GuiFontMetrics::maxDescent() const } +int GuiFontMetrics::em() const +{ + return QFontInfo(font_).pixelSize(); +} + + +int GuiFontMetrics::lineWidth() const +{ + return metrics_.lineWidth(); +} + + +int GuiFontMetrics::underlinePos() const +{ + return metrics_.underlinePos(); +} + + +int GuiFontMetrics::strikeoutPos() const +{ + return metrics_.strikeOutPos(); +} + + int GuiFontMetrics::lbearing(char_type c) const { if (!is_utf16(c)) - // FIXME: QFontMetrics::leftBearingdoes not support the + // FIXME: QFontMetrics::leftBearing does not support the // full unicode range. Once it does, we could use: - //return metrics_.leftBearing(toqstr(docstring(1,c))); + //return metrics_.leftBearing(toqstr(docstring(1, c))); return 0; return metrics_.leftBearing(ucs4_to_qchar(c)); } -int GuiFontMetrics::rbearing(char_type c) const -{ - if (!rbearing_cache_.contains(c)) { - // Qt rbearing is from the right edge of the char's width(). - int rb; - if (is_utf16(c)) { - QChar sc = ucs4_to_qchar(c); - rb = width(c) - metrics_.rightBearing(sc); - } else - // FIXME: QFontMetrics::leftBearingdoes not support the - // full unicode range. Once it does, we could use: - // metrics_.rightBearing(toqstr(docstring(1,c))); - rb = width(c); - - rbearing_cache_.insert(c, rb); - } - return rbearing_cache_.value(c); +namespace { +int const outOfLimitMetric = -10000; } -int GuiFontMetrics::smallcapsWidth(char_type c) const +int GuiFontMetrics::rbearing(char_type c) const { - // FIXME: Optimisation probably needed: we don't use the width cache. + int value = rbearing_cache_.value(c, outOfLimitMetric); + if (value != outOfLimitMetric) + return value; + + // Qt rbearing is from the right edge of the char's width(). if (is_utf16(c)) { - QChar const qc = ucs4_to_qchar(c); - QChar const uc = qc.toUpper(); - if (qc != uc) - return smallcaps_metrics_.width(uc); - else - return metrics_.width(qc); + QChar sc = ucs4_to_qchar(c); + value = width(c) - metrics_.rightBearing(sc); } else { - QString const s = toqstr(docstring(1,c)); - QString const us = s.toUpper(); - if (s != us) - return smallcaps_metrics_.width(us); - else - return metrics_.width(s); + // FIXME: QFontMetrics::leftBearing does not support the + // full unicode range. Once it does, we could use: + // metrics_.rightBearing(toqstr(docstring(1, c))); + value = width(c); } + + rbearing_cache_.insert(c, value); + + return value; } int GuiFontMetrics::width(docstring const & s) const { - size_t ls = s.size(); + PROFILE_THIS_BLOCK(width); + if (strwidth_cache_.contains(s)) + return strwidth_cache_[s]; + PROFILE_CACHE_MISS(width); + /* For some reason QMetrics::width returns a wrong value with Qt5 + * with some arabic text. OTOH, QTextLayout is broken for single + * characters with null width (like \not in mathed). Also, as a + * safety measure, always use QMetrics::width with our math fonts. + */ int w = 0; - for (unsigned int i = 0; i < ls; ++i) - w += width(s[i]); - + if (s.length() == 1 +#if QT_VERSION >= 0x040800 + || font_.styleName() == "LyX" +#endif + ) + w = metrics_.width(toqstr(s)); + else { + QTextLayout tl; + tl.setText(toqstr(s)); + tl.setFont(font_); + tl.beginLayout(); + QTextLine line = tl.createLine(); + tl.endLayout(); + w = int(line.naturalTextWidth()); + } + strwidth_cache_.insert(s, w, s.size() * sizeof(char_type)); return w; } @@ -140,24 +227,214 @@ int GuiFontMetrics::signedWidth(docstring const & s) const } +shared_ptr +GuiFontMetrics::getTextLayout(docstring const & s, bool const rtl, + double const wordspacing) const +{ + PROFILE_THIS_BLOCK(getTextLayout); + docstring const s_cache = + s + (rtl ? "r" : "l") + convert(wordspacing); + if (auto ptl = qtextlayout_cache_[s_cache]) + return ptl; + PROFILE_CACHE_MISS(getTextLayout); + auto const ptl = make_shared(); + ptl->setCacheEnabled(true); + ptl->setText(toqstr(s)); + QFont copy = font_; + copy.setWordSpacing(wordspacing); + ptl->setFont(copy); + // Note that both setFlags and the enums are undocumented + ptl->setFlags(rtl ? Qt::TextForceRightToLeft : Qt::TextForceLeftToRight); + ptl->beginLayout(); + ptl->createLine(); + ptl->endLayout(); + qtextlayout_cache_.insert(s_cache, ptl); + return ptl; +} + + +int GuiFontMetrics::pos2x(docstring const & s, int pos, bool const rtl, + double const wordspacing) const +{ + if (pos <= 0) + pos = 0; + shared_ptr tl = getTextLayout(s, rtl, wordspacing); + /* Since QString is UTF-16 and docstring is UCS-4, the offsets may + * not be the same when there are high-plan unicode characters + * (bug #10443). + */ + int const qpos = toqstr(s.substr(0, pos)).length(); + return static_cast(tl->lineForTextPosition(qpos).cursorToX(qpos)); +} + + +int GuiFontMetrics::x2pos(docstring const & s, int & x, bool const rtl, + double const wordspacing) const +{ + shared_ptr tl = getTextLayout(s, rtl, wordspacing); + int const qpos = tl->lineForTextPosition(0).xToCursor(x); + // correct x value to the actual cursor position. + x = static_cast(tl->lineForTextPosition(0).cursorToX(qpos)); + /* Since QString is UTF-16 and docstring is UCS-4, the offsets may + * not be the same when there are high-plan unicode characters + * (bug #10443). + */ +#if QT_VERSION < 0x040801 || QT_VERSION >= 0x050100 + return qstring_to_ucs4(tl->text().left(qpos)).length(); +#else + /* Due to QTBUG-25536 in 4.8.1 <= Qt < 5.1.0, the string returned + * by QString::toUcs4 (used by qstring_to_ucs4) may have wrong + * length. We work around the problem by trying all docstring + * positions until the right one is found. This is slow only if + * there are many high-plane Unicode characters. It might be + * worthwhile to implement a dichotomy search if this shows up + * under a profiler. + */ + int pos = min(qpos, static_cast(s.length())); + while (pos >= 0 && toqstr(s.substr(0, pos)).length() != qpos) + --pos; + LASSERT(pos > 0 || qpos == 0, /**/); + return pos; +#endif +} + + +int GuiFontMetrics::countExpanders(docstring const & str) const +{ + // Numbers of characters that are expanded by inter-word spacing. These + // characters are spaces, except for characters 09-0D which are treated + // specially. (From a combination of testing with the notepad found in qt's + // examples, and reading the source code.) In addition, consecutive spaces + // only count as one expander. + bool wasspace = false; + int nexp = 0; + for (char_type c : str) + if (c > 0x0d && QChar(c).isSpace()) { + if (!wasspace) { + ++nexp; + wasspace = true; + } + } else + wasspace = false; + return nexp; +} + + +pair +GuiFontMetrics::breakAt_helper(docstring const & s, int const x, + bool const rtl, bool const force) const +{ + QTextLayout tl; + /* Qt will not break at a leading or trailing space, and we need + * that sometimes, see http://www.lyx.org/trac/ticket/9921. + * + * To work around the problem, we enclose the string between + * zero-width characters so that the QTextLayout algorithm will + * agree to break the text at these extremal spaces. + */ + // Unicode character ZERO WIDTH NO-BREAK SPACE + QChar const zerow_nbsp(0xfeff); + QString qs = zerow_nbsp + toqstr(s) + zerow_nbsp; +#if 1 + /* Use unicode override characters to enforce drawing direction + * Source: http://www.iamcal.com/understanding-bidirectional-text/ + */ + if (rtl) + // Right-to-left override: forces to draw text right-to-left + qs = QChar(0x202E) + qs; + else + // Left-to-right override: forces to draw text left-to-right + qs = QChar(0x202D) + qs; + int const offset = 2; +#else + // Alternative version that breaks with Qt5 and arabic text (#10436) + // Note that both setFlags and the enums are undocumented + tl.setFlags(rtl ? Qt::TextForceRightToLeft : Qt::TextForceLeftToRight); + int const offset = 1; +#endif + + tl.setText(qs); + tl.setFont(font_); + QTextOption to; + to.setWrapMode(force ? QTextOption::WrapAtWordBoundaryOrAnywhere + : QTextOption::WordWrap); + tl.setTextOption(to); + tl.beginLayout(); + QTextLine line = tl.createLine(); + line.setLineWidth(x); + tl.createLine(); + tl.endLayout(); + if ((force && line.textLength() == offset) || int(line.naturalTextWidth()) > x) + return {-1, -1}; + /* Since QString is UTF-16 and docstring is UCS-4, the offsets may + * not be the same when there are high-plan unicode characters + * (bug #10443). + */ + // The variable `offset' is here to account for the extra leading characters. + // The ending character zerow_nbsp has to be ignored if the line is complete. + int const qlen = line.textLength() - offset - (line.textLength() == qs.length()); +#if QT_VERSION < 0x040801 || QT_VERSION >= 0x050100 + int len = qstring_to_ucs4(qs.mid(offset, qlen)).length(); +#else + /* Due to QTBUG-25536 in 4.8.1 <= Qt < 5.1.0, the string returned + * by QString::toUcs4 (used by qstring_to_ucs4) may have wrong + * length. We work around the problem by trying all docstring + * positions until the right one is found. This is slow only if + * there are many high-plane Unicode characters. It might be + * worthwhile to implement a dichotomy search if this shows up + * under a profiler. + */ + int len = min(qlen, static_cast(s.length())); + while (len >= 0 && toqstr(s.substr(0, len)).length() != qlen) + --len; + LASSERT(len > 0 || qlen == 0, /**/); +#endif + // The -1 is here to account for the leading zerow_nbsp. + return {len, int(line.naturalTextWidth())}; +} + + +bool GuiFontMetrics::breakAt(docstring & s, int & x, bool const rtl, bool const force) const +{ + PROFILE_THIS_BLOCK(breakAt); + if (s.empty()) + return false; + + docstring const s_cache = + s + convert(x) + (rtl ? "r" : "l") + (force ? "f" : "w"); + pair pp; + + if (breakat_cache_.contains(s_cache)) + pp = breakat_cache_[s_cache]; + else { + PROFILE_CACHE_MISS(breakAt); + pp = breakAt_helper(s, x, rtl, force); + breakat_cache_.insert(s_cache, pp, s_cache.size() * sizeof(char_type)); + } + if (pp.first == -1) + return false; + s = s.substr(0, pp.first); + x = pp.second; + return true; +} + + void GuiFontMetrics::rectText(docstring const & str, int & w, int & ascent, int & descent) const { - static int const d = 2; - w = width(str) + d * 2 + 2; + static int const d = Inset::TEXT_TO_INSET_OFFSET / 2; + + w = width(str) + Inset::TEXT_TO_INSET_OFFSET; ascent = metrics_.ascent() + d; descent = metrics_.descent() + d; } - void GuiFontMetrics::buttonText(docstring const & str, int & w, int & ascent, int & descent) const { - static int const d = 3; - w = width(str) + d * 2 + 2; - ascent = metrics_.ascent() + d; - descent = metrics_.descent() + d; + rectText(str, w, ascent, descent); + w += Inset::TEXT_TO_INSET_OFFSET; } @@ -173,53 +450,65 @@ Dimension const GuiFontMetrics::dimension(char_type c) const } -void GuiFontMetrics::fillMetricsCache(char_type c) const +GuiFontMetrics::AscendDescend const GuiFontMetrics::fillMetricsCache( + char_type c) const { QRect r; if (is_utf16(c)) r = metrics_.boundingRect(ucs4_to_qchar(c)); else - r = metrics_.boundingRect(toqstr(docstring(1,c))); + r = metrics_.boundingRect(toqstr(docstring(1, c))); AscendDescend ad = { -r.top(), r.bottom() + 1}; // We could as well compute the width but this is not really // needed for now as it is done directly in width() below. metrics_cache_.insert(c, ad); + + return ad; } int GuiFontMetrics::width(char_type c) const { - if (smallcaps_shape_) - return smallcapsWidth(c); + int value = width_cache_.value(c, outOfLimitMetric); + if (value != outOfLimitMetric) + return value; - if (!width_cache_.contains(c)) { - if (is_utf16(c)) - width_cache_.insert(c, metrics_.width(ucs4_to_qchar(c))); - else - width_cache_.insert(c, metrics_.width(toqstr(docstring(1,c)))); - } + if (is_utf16(c)) + value = metrics_.width(ucs4_to_qchar(c)); + else + value = metrics_.width(toqstr(docstring(1, c))); + + width_cache_.insert(c, value); - return width_cache_.value(c); + return value; } int GuiFontMetrics::ascent(char_type c) const { - if (!metrics_cache_.contains(c)) - fillMetricsCache(c); - - return metrics_cache_.value(c).ascent; + static AscendDescend const outOfLimitAD = + {outOfLimitMetric, outOfLimitMetric}; + AscendDescend value = metrics_cache_.value(c, outOfLimitAD); + if (value.ascent != outOfLimitMetric) + return value.ascent; + + value = fillMetricsCache(c); + return value.ascent; } int GuiFontMetrics::descent(char_type c) const { - if (!metrics_cache_.contains(c)) - fillMetricsCache(c); - - return metrics_cache_.value(c).descent; + static AscendDescend const outOfLimitAD = + {outOfLimitMetric, outOfLimitMetric}; + AscendDescend value = metrics_cache_.value(c, outOfLimitAD); + if (value.descent != outOfLimitMetric) + return value.descent; + + value = fillMetricsCache(c); + return value.descent; } -} // frontend -} // lyx +} // namespace frontend +} // namespace lyx