cached y positions patch from Alfredo

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@6785 a592a061-630c-0410-9148-cb99ea01b6c8

src/ChangeLog

@@ -1,3 +1,11 @@
+2003-04-11  Alfredo Braunstein  <abraunst@libero.it>
+
+	* lyxrow.[Ch]: add a cached y position to a Row and Row::y()
+	methods to access it.
+	* lyxtext.h:
+	* text.C: Added updateRowPositions to compute all row positions.
+	Make top_y and getRowNearY() to use the cached y position
+
 2003-04-11  John Levon  <levon@movementarian.org>
 
 	* text.C (rowBreakPoint): reintroduce the labelEnd

src/frontends/ChangeLog

@@ -1,3 +1,8 @@
+2003-04-11  Alfredo Braunstein  <abraunst@libero.it>
+
+	* screen.C (update): add calls to updateRowPositions() before
+	drawOneRow and drawFromTo.
+
 2003-04-10  John Levon  <levon@movementarian.org>
 
 	* Toolbar.h:

src/frontends/screen.C

@@ -257,6 +257,7 @@ void LyXScreen::update(BufferView & bv, int yo, int xo)
 	switch (text->refreshStatus()) {
 	case LyXText::REFRESH_AREA:
 	{
+		text->updateRowPositions();
 		int const y = max(int(text->refresh_y - text->top_y()), 0);
 		drawFromTo(text, &bv, y, vheight, yo, xo);
 		expose(0, y, vwidth, vheight - y);
@@ -264,6 +265,7 @@ void LyXScreen::update(BufferView & bv, int yo, int xo)
 	break;
 	case LyXText::REFRESH_ROW:
 	{
+		text->updateRowPositions();
 		// ok I will update the current cursor row
 		drawOneRow(text, &bv, text->refresh_row, text->refresh_y,
 			   yo, xo);
@@ -412,22 +414,18 @@ void LyXScreen::drawFromTo(LyXText * text, BufferView * bv,
 {
 	lyxerr[Debug::GUI] << "screen: drawFromTo " << y1 << '-' << y2 << endl;
 
-	int y_text = text->top_y() + y1;
-
-	// get the first needed row
-	RowList::iterator row = text->getRowNearY(y_text);
-	RowList::iterator end = text->rows().end();
-
-	// y_text is now the real beginning of the row
-
-	int y = y_text - text->top_y();
+	int const topy = text->top_y();
+	int y_text = topy + y1;
+	RowList::iterator rit = text->getRowNearY(y_text);
+	int y = y_text - topy;
 	// y1 is now the real beginning of row on the screen
 
-	while (row != end && y < y2) {
-		RowPainter rp(*bv, *text, row);
-		rp.paint(y + yo, xo, y + text->top_y());
-		y += row->height();
-		++row;
+	RowList::iterator const rend = text->rows().end();
+	while (rit != rend && y < y2) {
+		RowPainter rp(*bv, *text, rit);
+		rp.paint(y + yo, xo, y + topy);
+		y += rit->height();
+		++rit;
 	}
 
 	// maybe we have to clear the screen at the bottom

src/lyxrow.C

@@ -23,17 +23,29 @@ using std::max;
 using std::min;
 
 Row::Row()
-	: pos_(0), fill_(0), height_(0), width_(0),
+	: pos_(0), fill_(0), height_(0), width_(0), y_(0),
 	  ascent_of_text_(0), baseline_(0)
 {}
 
 
 Row::Row(ParagraphList::iterator pit, pos_type po)
-	: pit_(pit), pos_(po), fill_(0), height_(0), width_(0),
+	: pit_(pit), pos_(po), fill_(0), height_(0), width_(0), y_(0),
 	  ascent_of_text_(0), baseline_(0)
 {}
 
 
+void Row::y(unsigned int newy)
+{
+	y_ = newy;
+}
+
+
+unsigned int Row::y() const
+{
+	return y_;
+}
+
+
 ParagraphList::iterator Row::par()
 {
 	return pit_;

src/lyxrow.h

@@ -61,6 +61,10 @@ public:
 	unsigned int baseline() const;
 	/// return true if this row is the start of a paragraph
 	bool isParStart() const;
+	/// return the cached y position
+	unsigned int y() const;
+	/// cache the y position
+	void y(unsigned int newy);
 private:
 	///
 	ParagraphList::iterator pit_;
@@ -73,6 +77,8 @@ private:
 	unsigned short height_;
 	///
 	unsigned int width_;
+	/// cached y position
+	unsigned int y_;
 	/// ascent from baseline including prelude space
 	unsigned short ascent_of_text_;
 	/// the top of the real text in the row

src/lyxtext.h

@@ -88,6 +88,8 @@ private:
 	 */
 	int anchor_row_offset_;
 public:
+	/// update all cached row positions
+	void updateRowPositions();
 	/// get the y coord. of the top of the screen (relative to doc start)
 	int top_y() const;
 	/// set the y coord. of the top of the screen (relative to doc start)

src/text.C

@@ -74,25 +74,28 @@ BufferView * LyXText::bv() const
 }
 
 
-int LyXText::top_y() const
+void LyXText::updateRowPositions()
 {
-	if (anchor_row_ == rowlist_.end())
-		return 0;
-
-	int y = 0;
-
-	RowList::iterator rit = rowlist_.begin();
-	RowList::iterator end = rowlist_.end();
-	for (; rit != end && rit != anchor_row_; ++rit) {
+	RowList::iterator rit = rows().begin();
+	RowList::iterator rend = rows().end();
+	for (int y = 0; rit != rend ; ++rit) {
+		rit->y(y);
 		y += rit->height();
 	}
-	return y + anchor_row_offset_;
+}
+
+
+int LyXText::top_y() const
+{
+	if (isInInset() || anchor_row_ == rowlist_.end() )
+		return 0;
+	return anchor_row_->y() + anchor_row_offset_;
 }
 
 
 void LyXText::top_y(int newy)
 {
-	if (rows().empty())
+	if (rows().empty() || isInInset())
 		return;
 	lyxerr[Debug::GUI] << "setting top y = " << newy << endl;
 
@@ -2767,20 +2770,41 @@ LyXText::getRow(ParagraphList::iterator pit, pos_type pos, int & y) const
 
 RowList::iterator LyXText::getRowNearY(int & y) const
 {
-	// If possible we should optimize this method. (Lgb)
-	int tmpy = 0;
 
-	RowList::iterator rit = rowlist_.begin();
-	RowList::iterator end = rowlist_.end();
+	RowList::iterator rit = anchor_row_;
+	RowList::iterator const beg = rows().begin();
+	RowList::iterator const end = rows().end();
 
-	while (rit != end &&
-	       boost::next(rit) != end &&
-	       tmpy + rit->height() <= y) {
-		tmpy += rit->height();
-		++rit;
+	if (rows().empty()) {
+		y = 0;
+		return end;
+	}
+	if (rit == end)
+		rit = beg;
+
+	int tmpy = rit->y();
+
+	if (tmpy <= y) {
+		while (rit != end && tmpy <= y) {
+			tmpy += rit->height();
+			++rit;
+		}
+		if (rit != beg) {
+			--rit;
+			tmpy -= rit->height();
+		}
+	} else {
+		while (rit != beg && tmpy > y) {
+			--rit;
+			tmpy -= rit->height();
+		}
+	}
+	if (tmpy < 0 || rit == end) {
+		tmpy = 0;
+		rit = beg;
 	}
 
-	// return the real y
+	// return the rel y
 	y = tmpy;
 
 	return rit;

src/text2.C

@@ -283,7 +283,7 @@ void LyXText::removeRow(RowList::iterator rit)
 	if (anchor_row_ == rit) {
 		if (rit != rows().begin()) {
 			anchor_row_ = boost::prior(rit);
-			anchor_row_offset_ += boost::prior(rit)->height();
+			anchor_row_offset_ += anchor_row_->height();
 		} else {
 			anchor_row_ = boost::next(rit);
 			anchor_row_offset_ -= rit->height();