X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2FRow.cpp;h=3fb87bd7e1f3b80504742a85654fa361aca2c4b0;hb=4480b72a9dc8a5453a17edf55d4d4a60847a68ae;hp=1a3bb247f036c7e829f60c4d39ce2983aedf00e8;hpb=6258cebb77d63928313cae14bbba5d7f092d0a5e;p=lyx.git

diff --git a/src/Row.cpp b/src/Row.cpp
index 1a3bb247f0..3fb87bd7e1 100644
--- a/src/Row.cpp
+++ b/src/Row.cpp
@@ -24,99 +24,151 @@
 
 #include "support/debug.h"
 #include "support/lassert.h"
+#include "support/lstrings.h"
+#include "support/lyxalgo.h"
 
-#include <algorithm>
 #include <ostream>
 
 using namespace std;
 
 namespace lyx {
 
+using support::rtrim;
 using frontend::FontMetrics;
 
-double Row::Element::pos2x(pos_type const i) const
+
+// Maximum length that a space can be stretched when justifying text
+static double const MAX_SPACE_STRETCH = 1.5; //em
+
+
+int Row::Element::countSeparators() const
 {
-	bool const rtl = font.isVisibleRightToLeft();
+	if (type != STRING)
+		return 0;
+	return count(str.begin(), str.end(), ' ');
+}
 
-	// handle first the two bounds of the element
-	if ((!rtl && pos >= i) || (rtl && endpos <= i))
+
+int Row::Element::countExpanders() const
+{
+	if (type != STRING)
 		return 0;
-	if ((!rtl && endpos <= i) || (rtl && pos >= i))
-		return width();
+	return theFontMetrics(font).countExpanders(str);
+}
 
-	FontMetrics const & fm = theFontMetrics(font);
-	// FIXME Avoid caching of metrics there?
-	int const w = fm.width(str.substr(0, i - pos));
-	if (rtl)
-		return width() - w;
-	else
-		return w;
+
+int Row::Element::expansionAmount() const
+{
+	if (type != STRING)
+		return 0;
+	return countExpanders() * theFontMetrics(font).em();
 }
 
 
-pos_type Row::Element::x2pos(double &x, bool const low) const
+void Row::Element::setExtra(double extra_per_em)
 {
-	//lyxerr << "x2pos: x=" << x << " w=" << width() << " " << *this;
-	// if element is rtl, flip x value
-	bool const rtl = font.isVisibleRightToLeft();
-	double x2 = rtl ? (width() - x) : x;
+	if (type != STRING)
+		return;
+	extra = extra_per_em * theFontMetrics(font).em();
+}
+
+
+double Row::Element::pos2x(pos_type const i) const
+{
+	// This can happen with inline completion when clicking on the
+	// row after the completion.
+	if (i < pos || i > endpos)
+		return 0;
 
-	FontMetrics const & fm = theFontMetrics(font);
-	double last_w = 0;
 	double w = 0;
-	size_t i = 1;
-	// non-STRING element only contain one position
-	if (type != STRING) {
+	//handle first the two bounds of the element
+	if (i == endpos && type != VIRTUAL)
+		w = isRTL() ? 0 : full_width();
+	else if (i == pos || type != STRING)
+		w = isRTL() ? full_width() : 0;
+	else {
+		FontMetrics const & fm = theFontMetrics(font);
+		w = fm.pos2x(str, i - pos, isRTL(), extra);
+	}
+
+	return w;
+}
+
+
+pos_type Row::Element::x2pos(int &x) const
+{
+	//lyxerr << "x2pos: x=" << x << " w=" << width() << " " << *this;
+	size_t i = 0;
+
+	switch (type) {
+	case STRING: {
+		FontMetrics const & fm = theFontMetrics(font);
+		i = fm.x2pos(str, x, isRTL(), extra);
+		break;
+	}
+	case VIRTUAL:
+		// those elements are actually empty (but they have a width)
 		i = 0;
-		w = width();
-	} else {
-		// FIXME: implement dichotomy search?
-		for ( ; i <= str.size() ; ++i) {
-			last_w = w;
-			w = fm.width(str.substr(0,i));
-			if (w > x2) {
-				--i;
-				break;
-			}
+		x = isRTL() ? int(full_width()) : 0;
+		break;
+	case INSET:
+	case SPACE:
+		// those elements contain only one position. Round to
+		// the closest side.
+		if (x > (full_width() + 1) / 2) {
+			x = int(full_width());
+			i = !isRTL();
+		} else {
+			x = 0;
+			i = isRTL();
 		}
-		// if (i == str.size())
-		// 	lyxerr << " NOT FOUND ";
 	}
+	//lyxerr << "=> p=" << pos + i << " x=" << x << endl;
+	return pos + i;
+}
 
-	// round to the closest side
-	if (!low && (x2 - last_w > w - x2)) {
-		x2 = w;
-		++i;
-	} else
-		x2 = last_w;
 
-	// is element is rtl, flip values
-	if (rtl) {
-		x = width() - x2;
-	} else {
-		x = x2;
+bool Row::Element::breakAt(int w, bool force)
+{
+	if (type != STRING || dim.wid <= w)
+		return false;
+
+	FontMetrics const & fm = theFontMetrics(font);
+	int x = w;
+	if(fm.breakAt(str, x, isRTL(), force)) {
+		dim.wid = x;
+		endpos = pos + str.length();
+		//lyxerr << "breakAt(" << w << ")  Row element Broken at " << x << "(w(str)=" << fm.width(str) << "): e=" << *this << endl;
+		return true;
 	}
 
-	//lyxerr << "=> p=" << i << " x=" << x << endl;
-	return pos + i;
+	return false;
 }
 
 
-Row::Row()
-	: separator(0), label_hfill(0), x(0), right_margin(0),
-	  sel_beg(-1), sel_end(-1),
-	  begin_margin_sel(false), end_margin_sel(false),
-	  changed_(false), crc_(0), pos_(0), end_(0), right_boundary_(false)
-{}
+pos_type Row::Element::left_pos() const
+{
+	return isRTL() ? endpos : pos;
+}
 
 
-void Row::setCrc(size_type crc) const
+pos_type Row::Element::right_pos() const
 {
-	changed_ = crc != crc_;
-	crc_ = crc;
+	return isRTL() ? pos : endpos;
 }
 
 
+Row::Row()
+	: separator(0), label_hfill(0), left_margin(0), right_margin(0),
+	  sel_beg(-1), sel_end(-1),
+	  begin_margin_sel(false), end_margin_sel(false),
+	  changed_(true),
+	  pit_(0), pos_(0), end_(0),
+	  right_boundary_(false), flushed_(false), rtl_(false),
+	  changebar_(false)
+{}
+
+
 bool Row::isMarginSelected(bool left_margin, DocIterator const & beg,
 		DocIterator const & end) const
 {
@@ -151,8 +203,8 @@ void Row::setSelectionAndMargins(DocIterator const & beg,
 	setSelection(beg.pos(), end.pos());
 
 	if (selection()) {
-		end_margin_sel = isMarginSelected(false, beg, end);
-		begin_margin_sel = isMarginSelected(true, beg, end);
+		change(end_margin_sel, isMarginSelected(false, beg, end));
+		change(begin_margin_sel, isMarginSelected(true, beg, end));
 	}
 }
 
@@ -160,18 +212,18 @@ void Row::setSelectionAndMargins(DocIterator const & beg,
 void Row::setSelection(pos_type beg, pos_type end) const
 {
 	if (pos_ >= beg && pos_ <= end)
-		sel_beg = pos_;
+		change(sel_beg, pos_);
 	else if (beg > pos_ && beg <= end_)
-		sel_beg = beg;
+		change(sel_beg, beg);
 	else
-		sel_beg = -1;
+		change(sel_beg, -1);
 
 	if (end_ >= beg && end_ <= end)
-		sel_end = end_;
+		change(sel_end,end_);
 	else if (end < end_ && end >= pos_)
-		sel_end = end;
+		change(sel_end, end);
 	else
-		sel_end = -1;
+		change(sel_end, -1);
 }
 
 
@@ -183,28 +235,27 @@ bool Row::selection() const
 
 ostream & operator<<(ostream & os, Row::Element const & e)
 {
-	if (e.font.isVisibleRightToLeft())
+	if (e.isRTL())
 		os << e.endpos << "<<" << e.pos << " ";
 	else
 		os << e.pos << ">>" << e.endpos << " ";
 
 	switch (e.type) {
 	case Row::STRING:
-		os << "STRING: `" << to_utf8(e.str) << "' " << e.dim.wid;
+		os << "STRING: `" << to_utf8(e.str) << "' ("
+		   << e.countExpanders() << " expanders.), ";
 		break;
 	case Row::VIRTUAL:
-		os << "VIRTUAL: `" << to_utf8(e.str) << "'";
+		os << "VIRTUAL: `" << to_utf8(e.str) << "', ";
 		break;
 	case Row::INSET:
-		os << "INSET: " << to_utf8(e.inset->layoutName());
-		break;
-	case Row::SEPARATOR:
-		os << "SEPARATOR: " << e.dim.wid << "+" << e.extra;
+		os << "INSET: " << to_utf8(e.inset->layoutName()) << ", ";
 		break;
 	case Row::SPACE:
-		os << "SPACE: " << e.dim.wid;
+		os << "SPACE: ";
 		break;
 	}
+	os << "width=" << e.full_width();
 	return os;
 }
 
@@ -212,20 +263,90 @@ ostream & operator<<(ostream & os, Row::Element const & e)
 ostream & operator<<(ostream & os, Row const & row)
 {
 	os << " pos: " << row.pos_ << " end: " << row.end_
-	   << " x: " << row.x
+	   << " left_margin: " << row.left_margin
 	   << " width: " << row.dim_.wid
+	   << " right_margin: " << row.right_margin
 	   << " ascent: " << row.dim_.asc
 	   << " descent: " << row.dim_.des
 	   << " separator: " << row.separator
-	   << " label_hfill : " << row.label_hfill << "\n";
+	   << " label_hfill: " << row.label_hfill
+	   << " row_boundary: " << row.right_boundary() << "\n";
+	double x = row.left_margin;
 	Row::Elements::const_iterator it = row.elements_.begin();
 	for ( ; it != row.elements_.end() ; ++it) {
-		os << "** " << *it << endl;
+		os << "x=" << x << " => " << *it << endl;
+		x += it->full_width();
 	}
 	return os;
 }
 
 
+int Row::left_x() const
+{
+	double x = left_margin;
+	const_iterator const end = elements_.end();
+	const_iterator cit = elements_.begin();
+	while (cit != end && cit->isVirtual()) {
+		x += cit->full_width();
+		++cit;
+	}
+	return int(x + 0.5);
+}
+
+
+int Row::right_x() const
+{
+	double x = dim_.wid;
+	const_iterator const begin = elements_.begin();
+	const_iterator cit = elements_.end();
+	while (cit != begin) {
+		--cit;
+		if (cit->isVirtual())
+			x -= cit->full_width();
+		else
+			break;
+	}
+	return int(x + 0.5);
+}
+
+
+int Row::countSeparators() const
+{
+	int n = 0;
+	const_iterator const end = elements_.end();
+	for (const_iterator cit = elements_.begin() ; cit != end ; ++cit)
+		n += cit->countSeparators();
+	return n;
+}
+
+
+bool Row::setExtraWidth(int w)
+{
+	if (w < 0)
+		// this is not expected to happen (but it does)
+		return false;
+	// amount of expansion: number of expanders time the em value for each
+	// string element
+	int exp_amount = 0;
+	for (Row::Element const & e : elements_)
+		exp_amount += e.expansionAmount();
+	if (!exp_amount)
+		return false;
+	// extra length per expander per em
+	double extra_per_em = double(w) / exp_amount;
+	if (extra_per_em > MAX_SPACE_STRETCH)
+		// do not stretch more than MAX_SPACE_STRETCH em per expander
+		return false;
+	// add extra length to each element proportionally to its em.
+	for (Row::Element & e : elements_)
+		if (e.type == Row::STRING)
+			e.setExtra(extra_per_em);
+	// update row dimension
+	dim_.wid += w;
+	return true;
+}
+
+
 bool Row::sameString(Font const & f, Change const & ch) const
 {
 	if (elements_.empty())
@@ -244,8 +365,11 @@ void Row::finalizeLast()
 	if (elt.final)
 		return;
 	elt.final = true;
+	if (elt.change.changed())
+		changebar_ = true;
 
 	if (elt.type == STRING) {
+		dim_.wid -= elt.dim.wid;
 		elt.dim.wid = theFontMetrics(elt.font).width(elt.str);
 		dim_.wid += elt.dim.wid;
 	}
@@ -272,9 +396,16 @@ void Row::add(pos_type const pos, char_type const c,
 		Element e(STRING, pos, f, ch);
 		elements_.push_back(e);
 	}
-	//lyxerr << "FONT " <<back().font.language() << endl;
-	back().str += c;
-	back().endpos = pos + 1;
+	if (back().str.length() % 30 == 0) {
+		dim_.wid -= back().dim.wid;
+		back().str += c;
+		back().endpos = pos + 1;
+		back().dim.wid = theFontMetrics(back().font).width(back().str);
+		dim_.wid += back().dim.wid;
+	} else {
+		back().str += c;
+		back().endpos = pos + 1;
+	}
 }
 
 
@@ -284,25 +415,14 @@ void Row::addVirtual(pos_type const pos, docstring const & s,
 	finalizeLast();
 	Element e(VIRTUAL, pos, f, ch);
 	e.str = s;
-	// A completion has no size
+	e.dim.wid = theFontMetrics(f).width(s);
+	dim_.wid += e.dim.wid;
 	e.endpos = pos;
 	elements_.push_back(e);
 	finalizeLast();
 }
 
 
-void Row::addSeparator(pos_type const pos, char_type const c,
-		       Font const & f, Change const & ch)
-{
-	finalizeLast();
-	Element e(SEPARATOR, pos, f, ch);
-	e.str += c;
-	e.dim.wid = theFontMetrics(f).width(c);
-	elements_.push_back(e);
-	dim_.wid += e.dim.wid;
-}
-
-
 void Row::addSpace(pos_type const pos, int const width,
 		   Font const & f, Change const & ch)
 {
@@ -321,83 +441,176 @@ void Row::pop_back()
 }
 
 
-void Row::shorten_if_needed(pos_type const keep, int const w)
+bool Row::shortenIfNeeded(pos_type const keep, int const w, int const next_width)
 {
-	if (empty() || width() < w)
-		return;
+	if (empty() || width() <= w)
+		return false;
 
-	/** First, we try to remove elements one by one from the end
-	 * until a separator is found.
-	 */
-	int i = elements_.size();
-	int new_end = end_;
-	int new_wid = dim_.wid;
-	if (i > 0 && elements_[i - 1].type == SEPARATOR && new_end > keep) {
-		--i;
-		new_end = elements_[i].pos;
-		new_wid -= elements_[i].dim.wid;
+	Elements::iterator const beg = elements_.begin();
+	Elements::iterator const end = elements_.end();
+	int wid = left_margin;
+
+	// Search for the first element that goes beyond right margin
+	Elements::iterator cit = beg;
+	for ( ; cit != end ; ++cit) {
+		if (wid + cit->dim.wid > w)
+			break;
+		wid += cit->dim.wid;
 	}
 
-	while (i > 0 && elements_[i - 1].type != SEPARATOR && new_end > keep) {
-		--i;
-		new_end = elements_[i].pos;
-		new_wid -= elements_[i].dim.wid;
+	if (cit == end) {
+		// This should not happen since the row is too long.
+		LYXERR0("Something is wrong cannot shorten row: " << *this);
+		return false;
 	}
-	if (i == 0) {
-		/* If we are here, it means that we have not found a
-		 * separator to shorten the row. There is one case
-		 * where we can do something: when we have one big
-		 * string, maybe with a paragraph marker after it.
+
+	// Iterate backwards over breakable elements and try to break them
+	Elements::iterator cit_brk = cit;
+	int wid_brk = wid + cit_brk->dim.wid;
+	++cit_brk;
+	while (cit_brk != beg) {
+		--cit_brk;
+		// make a copy of the element to work on it.
+		Element brk = *cit_brk;
+		wid_brk -= brk.dim.wid;
+		if (brk.countSeparators() == 0 || brk.pos < keep)
+			continue;
+		/* We have found a suitable separable element. This is the common case.
+		 * Try to break it cleanly (at word boundary) at a length that is both
+		 * - less than the available space on the row
+		 * - shorter than the natural width of the element, in order to enforce
+		 *   break-up.
 		 */
-		Element & front = elements_.front();
-		if (!(front.type == STRING
-		      && (elements_.size() == 1
-			  || (elements_.size() == 2
-			      && back().type == VIRTUAL))))
-			return;
-
-		// If this is a string element, we can try to split it.
-		if (front.type != STRING)
-			return;
-		double xstr = w - x;
-		// If there is a paragraph marker, it should be taken in account
-		if (elements_.size() == 2)
-			xstr -= back().width();
-		pos_type new_pos = front.x2pos(xstr, true);
-		front.str = front.str.substr(0, new_pos - pos_);
-		front.dim.wid = xstr;
-		front.endpos = new_pos;
-		end_ = new_pos;
-		dim_.wid = x + xstr;
-		// If there is a paragraph marker, it should be removed.
-		if (elements_.size() == 2)
-			elements_.pop_back();
-		return;
+		if (brk.breakAt(min(w - wid_brk, brk.dim.wid - 2), false)) {
+			/* if this element originally did not cause a row overflow
+			 * in itself, and the remainder of the row would still be
+			 * too large after breaking, then we will have issues in
+			 * next row. Thus breaking does not help.
+			 */
+			if (wid_brk + cit_brk->dim.wid < w
+			    && dim_.wid - (wid_brk + brk.dim.wid) >= next_width) {
+				break;
+			}
+			end_ = brk.endpos;
+			/* after breakAt, there may be spaces at the end of the
+			 * string, but they are not counted in the string length
+			 * (QTextLayout feature, actually). We remove them, but do
+			 * not change the end of the row, since spaces at row
+			 * break are invisible.
+			 */
+			brk.str = rtrim(brk.str);
+			brk.endpos = brk.pos + brk.str.length();
+			*cit_brk = brk;
+			dim_.wid = wid_brk + brk.dim.wid;
+			// If there are other elements, they should be removed.
+			elements_.erase(cit_brk + 1, end);
+			return true;
+		}
+	}
+
+	if (cit != beg && cit->type == VIRTUAL) {
+		// It is not possible to separate a virtual element from the
+		// previous one.
+		--cit;
+		wid -= cit->dim.wid;
 	}
-	end_ = new_end;
-	dim_.wid = new_wid;
-	elements_.erase(elements_.begin() + i, elements_.end());
+
+	if (cit != beg) {
+		// There is no usable separator, but several elements have
+		// been added. We can cut right here.
+		end_ = cit->pos;
+		dim_.wid = wid;
+		elements_.erase(cit, end);
+		return true;
+	}
+
+	/* If we are here, it means that we have not found a separator to
+	 * shorten the row. Let's try to break it again, but not at word
+	 * boundary this time.
+	 */
+	if (cit->breakAt(w - wid, true)) {
+		end_ = cit->endpos;
+		// See comment above.
+		cit->str = rtrim(cit->str);
+		cit->endpos = cit->pos + cit->str.length();
+		dim_.wid = wid + cit->dim.wid;
+		// If there are other elements, they should be removed.
+		elements_.erase(next(cit, 1), end);
+		return true;
+	}
+	return false;
 }
 
 
-void Row::reverseRTL()
+void Row::reverseRTL(bool const rtl_par)
 {
 	pos_type i = 0;
 	pos_type const end = elements_.size();
 	while (i < end) {
-		// skip LtR elements
-		while (i < end && !elements_[i].font.isRightToLeft())
-			++i;
-		if (i >= end)
-			break;
-
-		// look for a RTL sequence
+		// gather a sequence of elements with the same direction
+		bool const rtl = elements_[i].isRTL();
 		pos_type j = i;
-		while (j < end && elements_[j].font.isRightToLeft())
+		while (j < end && elements_[j].isRTL() == rtl)
 			++j;
-		reverse(elements_.begin() + i, elements_.begin() + j);
+		// if the direction is not the same as the paragraph
+		// direction, the sequence has to be reverted.
+		if (rtl != rtl_par)
+			reverse(elements_.begin() + i, elements_.begin() + j);
 		i = j;
 	}
+	// If the paragraph itself is RTL, reverse everything
+	if (rtl_par)
+		reverse(elements_.begin(), elements_.end());
+	rtl_ = rtl_par;
 }
 
+Row::const_iterator const
+Row::findElement(pos_type const pos, bool const boundary, double & x) const
+{
+	/**
+	 * When boundary is true, position i is in the row element (pos, endpos)
+	 * if
+	 *    pos < i <= endpos
+	 * whereas, when boundary is false, the test is
+	 *    pos <= i < endpos
+	 * The correction below allows to handle both cases.
+	*/
+	int const boundary_corr = (boundary && pos) ? -1 : 0;
+
+	x = left_margin;
+
+	/** Early return in trivial cases
+	 * 1) the row is empty
+	 * 2) the position is the left-most position of the row; there
+	 * is a quirk here however: if the first element is virtual
+	 * (end-of-par marker for example), then we have to look
+	 * closer
+	 */
+	if (empty()
+	    || (pos == begin()->left_pos() && !boundary
+			&& !begin()->isVirtual()))
+		return begin();
+
+	Row::const_iterator cit = begin();
+	for ( ; cit != end() ; ++cit) {
+		/** Look whether the cursor is inside the element's
+		 * span. Note that it is necessary to take the
+		 * boundary into account, and to accept virtual
+		 * elements, which have pos == endpos.
+		 */
+		if (pos + boundary_corr >= cit->pos
+		    && (pos + boundary_corr < cit->endpos || cit->isVirtual())) {
+				x += cit->pos2x(pos);
+				break;
+		}
+		x += cit->full_width();
+	}
+
+	if (cit == end())
+		--cit;
+
+	return cit;
+}
+
+
 } // namespace lyx