Allow automatic text direction in Painter::text()

It is wrong to assume that direction is left-to-right when no indication exist.

Add a new enum with values LtR, RtL and Auto to be used as argument of
the private text() methods. When direction is Auto, let Qt decide how
the string shall be layed out.

This is reimplementation of 51ee267c. A direct cherry-pick was not possible.

Fixes bug #10169.

diff --git a/src/frontends/Painter.h b/src/frontends/Painter.h
index c72d8133b972e05e9e070221efd3d3919a90eab8..e2f547bd85e927adcf6a633c26b79ec067f3b1bf 100644 (file)
--- a/src/frontends/Painter.h
+++ b/src/frontends/Painter.h
@@ -133,15 +133,14 @@ public:
        virtual void image(int x, int y, int w, int h,
                graphics::Image const & image) = 0;
 
-       /** draw a string at position x, y (y is the baseline). The
-        * text direction is given by \c rtl.
+       /** draw a string at position x, y (y is the baseline). The text
+        * direction depends on the string itself.
         * \return the width of the drawn text.
         */
-       virtual int text(int x, int y, docstring const & str, FontInfo const & f,
-                     bool rtl = false, double wordspacing = 0.0) = 0;
+       virtual int text(int x, int y, docstring const & str, FontInfo const & f) = 0;
 
-       /** draw a string at position x, y (y is the baseline). The
-        * text direction is enforced by the \c Font.
+       /** draw a string at position x, y (y is the baseline). The text
+        * direction is enforced by the \c Font.
         * \return the width of the drawn text.
         */
        virtual int text(int x, int y, docstring const & str, Font const & f,

diff --git a/src/frontends/qt4/GuiPainter.cpp b/src/frontends/qt4/GuiPainter.cpp
index 495a11a8a6f036892bb9d088364bb06e228e0583..f1eb35e8e8f5cfe59506d431eef76fdf9705f840 100644 (file)
--- a/src/frontends/qt4/GuiPainter.cpp
+++ b/src/frontends/qt4/GuiPainter.cpp
@@ -333,7 +333,14 @@ int GuiPainter::text(int x, int y, char_type c, FontInfo const & f)
 }
 
 
-void GuiPainter::do_drawText(int x, int y, QString str, bool rtl, FontInfo const & f, QFont ff)
+int GuiPainter::text(int x, int y, docstring const & s, FontInfo const & f)
+{
+       return text(x, y, s, f, Auto, 0.0);
+}
+
+
+void GuiPainter::do_drawText(int x, int y, QString str, Direction const dir,
+                             FontInfo const & f, QFont ff)
 {
        setQPainterPen(computeColor(f.realColor()));
        if (font() != ff)
@@ -346,10 +353,10 @@ void GuiPainter::do_drawText(int x, int y, QString str, bool rtl, FontInfo const
        /* Use unicode override characters to enforce drawing direction
         * Source: http://www.iamcal.com/understanding-bidirectional-text/
         */
-       if (rtl)
+       if (dir == RtL)
                // Right-to-left override: forces to draw text right-to-left
                str = QChar(0x202E) + str;
-       else
+       else if (dir == LtR)
                // Left-to-right override: forces to draw text left-to-right
                str =  QChar(0x202D) + str;
        drawText(x, y, str);
@@ -360,8 +367,12 @@ void GuiPainter::do_drawText(int x, int y, QString str, bool rtl, FontInfo const
         * Keep it here for now, in case it can be helpful
         */
        //This is much stronger than setLayoutDirection.
-       int flag = rtl ? Qt::TextForceRightToLeft : Qt::TextForceLeftToRight;
-       drawText(x + (rtl ? textwidth : 0), y - fm.maxAscent(), 0, 0,
+       int flag = 0;
+       if (dir == RtL)
+               flag = Qt::TextForceRightToLeft;
+       else if (dir == LtR)
+               flag = Qt::TextForceLeftToRight;
+       drawText(x + ((dir == RtL) ? textwidth : 0), y - fm.maxAscent(), 0, 0,
                 flag | Qt::TextDontClip,
                 str);
 #endif
@@ -369,7 +380,7 @@ void GuiPainter::do_drawText(int x, int y, QString str, bool rtl, FontInfo const
 
 
 int GuiPainter::text(int x, int y, docstring const & s,
-                     FontInfo const & f, bool const rtl,
+                     FontInfo const & f, Direction const dir,
                      double const wordspacing)
 {
        //LYXERR0("text: x=" << x << ", s=" << s);
@@ -421,7 +432,7 @@ int GuiPainter::text(int x, int y, docstring const & s,
                // Only the left bearing of the first character is important
                // as we always write from left to right, even for
                // right-to-left languages.
-               // FIXME: this is probably broken for RTL now that we draw full strings.
+               // FIXME: this is probably broken for RtL now that we draw full strings.
                // Morover the first/last element is possibly not the right one since the glyph may have changed.
                int const lb = min(fm.lbearing(s[0]), 0);
                int const mA = fm.maxAscent();
@@ -446,7 +457,7 @@ int GuiPainter::text(int x, int y, docstring const & s,
 #endif
                        pm.fill(Qt::transparent);
                        GuiPainter p(&pm, pixelRatio());
-                       p.do_drawText(-lb, mA, str, rtl, f, ff);
+                       p.do_drawText(-lb, mA, str, dir, f, ff);
                        QPixmapCache::insert(key, pm);
                        //LYXERR(Debug::PAINTING, "h=" << h << "  mA=" << mA << "  mD=" << mD
                        //      << "  w=" << w << "  lb=" << lb << "  tw=" << textwidth
@@ -460,7 +471,7 @@ int GuiPainter::text(int x, int y, docstring const & s,
        }
 
        // don't use the pixmap cache,
-       do_drawText(x, y, str, rtl, f, ff);
+       do_drawText(x, y, str, dir, f, ff);
        //LYXERR(Debug::PAINTING, "draw " << string(str.toUtf8())
        //      << " at " << x << "," << y);
        return textwidth;
@@ -470,7 +481,7 @@ int GuiPainter::text(int x, int y, docstring const & s,
 int GuiPainter::text(int x, int y, docstring const & str, Font const & f,
                      double const wordspacing)
 {
-       return text(x, y, str, f.fontInfo(), f.isVisibleRightToLeft(), wordspacing);
+       return text(x, y, str, f.fontInfo(), f.isVisibleRightToLeft() ? RtL : LtR, wordspacing);
 }
 
 
@@ -480,13 +491,13 @@ int GuiPainter::text(int x, int y, docstring const & str, Font const & f,
 {
        GuiFontMetrics const & fm = getFontMetrics(f.fontInfo());
        FontInfo fi = f.fontInfo();
-       bool const rtl = f.isVisibleRightToLeft();
+       Direction const dir = f.isVisibleRightToLeft() ? RtL : LtR;
 
        // dimensions
        int const ascent = fm.maxAscent();
        int const height = fm.maxAscent() + fm.maxDescent();
-       int xmin = fm.pos2x(str, from, rtl, wordspacing);
-       int xmax = fm.pos2x(str, to, rtl, wordspacing);
+       int xmin = fm.pos2x(str, from, dir == RtL, wordspacing);
+       int xmax = fm.pos2x(str, to, dir == RtL, wordspacing);
        if (xmin > xmax)
                swap(xmin, xmax);
 
@@ -495,7 +506,7 @@ int GuiPainter::text(int x, int y, docstring const & str, Font const & f,
        fi.setPaintColor(other);
        QRegion const clip(x + xmin, y - ascent, xmax - xmin, height);
        setClipRegion(clip);
-       int const textwidth = text(x, y, str, fi, rtl, wordspacing);
+       int const textwidth = text(x, y, str, fi, dir, wordspacing);
 
        // Then the part in normal color
        // Note that in Qt5, it is not possible to use Qt::UniteClip,
@@ -503,7 +514,7 @@ int GuiPainter::text(int x, int y, docstring const & str, Font const & f,
        fi.setPaintColor(orig);
        QRegion region(viewport());
        setClipRegion(region - clip);
-       text(x, y, str, fi, rtl, wordspacing);
+       text(x, y, str, fi, dir, wordspacing);
        setClipping(false);
 
        return textwidth;

diff --git a/src/frontends/qt4/GuiPainter.h b/src/frontends/qt4/GuiPainter.h
index 5aec66ac4c453edb0bf65331e21612c188e99cae..83aa72b4f37e1205d6c59e27cfaf22bf245a07ed 100644 (file)
--- a/src/frontends/qt4/GuiPainter.h
+++ b/src/frontends/qt4/GuiPainter.h
@@ -105,15 +105,14 @@ public:
        virtual void image(int x, int y, int w, int h,
                lyx::graphics::Image const & image);
 
-       /** draw a string at position x, y (y is the baseline). The
-        * text direction is given by \c rtl.
+       /** draw a string at position x, y (y is the baseline). The text
+        * direction depends on the string itself.
         * \return the width of the drawn text.
         */
-       virtual int text(int x, int y, docstring const & str, FontInfo const & f,
-                     bool rtl = false, double wordspacing = 0.0);
+       virtual int text(int x, int y, docstring const & str, FontInfo const & f);
 
-       /** draw a string at position x, y (y is the baseline). The
-        * text direction is enforced by the \c Font.
+       /** draw a string at position x, y (y is the baseline). The text
+        * direction is enforced by the \c Font.
         * \return the width of the drawn text.
         */
        virtual int text(int x, int y, docstring const & str, Font const & f,
@@ -186,8 +185,14 @@ private:
        void setQPainterPen(QColor const & col,
                line_style ls = line_solid, int lw = thin_line);
 
-       // Helper for text() method
-       void do_drawText(int x, int y, QString str, bool rtl, FontInfo const & f, QFont ff);
+       /// Direction for painting text
+       enum Direction { LtR, RtL, Auto };
+
+       /// Helpers for text() method
+       void do_drawText(int x, int y, QString str, Direction dir, FontInfo const & f, QFont ff);
+       ///
+       virtual int text(int x, int y, docstring const & str, FontInfo const & f,
+                     Direction dir, double wordspacing);
 
        QColor current_color_;
        Painter::line_style current_ls_;

diff --git a/status.22x b/status.22x
index ac5de96bf34f905a4b9088a095010854498afcf5..ed19ebc9e3713204f1dbb1f5eb7398b90ef49a0c 100644 (file)
--- a/status.22x
+++ b/status.22x
@@ -45,6 +45,8 @@ What's new
 
 * USER INTERFACE
 
+- Fix display of labels in right-to-left languages (bug 10169).
+
 - When a counter is stepped, reset recursively all subcounters (bug #10063).
 
 - Fix on screen narrow box when using \width as box width unit (bug 10048).