From 96fee0ed7acdd9d757d59b126f07631176e2d96f Mon Sep 17 00:00:00 2001
From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Mon, 29 Feb 2016 16:05:06 +0100
Subject: [PATCH] Move some horizontal scrolling code from TextMetrics to
 BufferView

It is better to have all the code in the same place, and it will avoid code duplication later.
---
 src/BufferView.cpp  | 21 ++++++++++++++++-----
 src/BufferView.h    | 15 +++++++++------
 src/TextMetrics.cpp | 24 +++++-------------------
 3 files changed, 30 insertions(+), 30 deletions(-)

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index 1daee5c720..9708a08aeb 100644
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -2914,15 +2914,26 @@ int BufferView::horizScrollOffset() const
 }
 
 
-CursorSlice const & BufferView::currentRowSlice() const
-{
-	return d->current_row_slice_;
+int BufferView::horizScrollOffset(Text const * text,
+                                  pit_type pit, pos_type pos) const
+{
+	// Is this a row that is currently scrolled?
+	if (!d->current_row_slice_.empty()
+	    && &text->inset() == d->current_row_slice_.inset().asInsetText()
+	    && pit ==  d->current_row_slice_.pit()
+	    && pos ==  d->current_row_slice_.pos())
+		return d->horiz_scroll_offset_;
+	return 0;
 }
 
 
-CursorSlice const & BufferView::lastRowSlice() const
+bool BufferView::hadHorizScrollOffset(Text const * text,
+                                      pit_type pit, pos_type pos) const
 {
-	return d->last_row_slice_;
+	return !d->last_row_slice_.empty()
+	       && &text->inset() == d->last_row_slice_.inset().asInsetText()
+	       && pit ==  d->last_row_slice_.pit()
+	       && pos ==  d->last_row_slice_.pos();
 }
 
 
diff --git a/src/BufferView.h b/src/BufferView.h
index 31b6e94fc4..f57801f6a3 100644
--- a/src/BufferView.h
+++ b/src/BufferView.h
@@ -125,12 +125,15 @@ public:
 	// Returns the amount of horizontal scrolling applied to the
 	// top-level row where the cursor lies
 	int horizScrollOffset() const;
-
-	// Points to the top-level row where the cursor lies (during draw).
-	CursorSlice const & currentRowSlice() const;
-
-	// Points to the top-level row where the cursor lied at last draw event.
-	CursorSlice const & lastRowSlice() const;
+	// Returns the amount of horizontal scrolling applied to the
+	// row of text starting at (pit, pos)
+	int horizScrollOffset(Text const * text,
+	                      pit_type pit, pos_type pos) const;
+
+	// Returns true if the row of text starting at (pit, pos) was scrolled
+	// at the last draw event.
+	bool hadHorizScrollOffset(Text const * text,
+                              pit_type pit, pos_type pos) const;
 
 	/// reset the scrollbar to reflect current view position.
 	void updateScrollbar();
diff --git a/src/TextMetrics.cpp b/src/TextMetrics.cpp
index e69ffe9c22..80ee0aac7f 100644
--- a/src/TextMetrics.cpp
+++ b/src/TextMetrics.cpp
@@ -1113,14 +1113,8 @@ pos_type TextMetrics::getPosNearX(Row const & row, int & x,
 	int const xo = origin_.x_;
 	x -= xo;
 
-	int offset = 0;
-	CursorSlice rowSlice(const_cast<InsetText &>(text_->inset()));
-	rowSlice.pit() = row.pit();
-	rowSlice.pos() = row.pos();
-
 	// Adapt to cursor row scroll offset if applicable.
-	if (bv_->currentRowSlice() == rowSlice)
-		offset = bv_->horizScrollOffset();
+	int const offset = bv_->horizScrollOffset(text_, row.pit(), row.pos());
 	x += offset;
 
 	pos_type pos = row.pos();
@@ -1908,26 +1902,18 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type const pit, int const
 	for (size_t i = 0; i != nrows; ++i) {
 
 		Row const & row = pm.rows()[i];
-		int row_x = x;
+		// Adapt to cursor row scroll offset if applicable.
+		int row_x = x - bv_->horizScrollOffset(text_, pit, row.pos());
 		if (i)
 			y += row.ascent();
 
-		CursorSlice rowSlice(const_cast<InsetText &>(text_->inset()));
-		rowSlice.pit() = pit;
-		rowSlice.pos() = row.pos();
+		RowPainter rp(pi, *text_, pit, row, row_x, y);
 
 		bool const inside = (y + row.descent() >= 0
 			&& y - row.ascent() < ww);
-
-		// Adapt to cursor row scroll offset if applicable.
-		if (bv_->currentRowSlice() == rowSlice)
-			row_x -= bv_->horizScrollOffset();
-
 		// It is not needed to draw on screen if we are not inside.
 		pi.pain.setDrawingEnabled(inside && original_drawing_state);
 
-		RowPainter rp(pi, *text_, pit, row, row_x, y);
-
 		if (selection)
 			row.setSelectionAndMargins(sel_beg_par, sel_end_par);
 		else
@@ -1946,7 +1932,7 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type const pit, int const
 		if (pi.pain.isDrawingEnabled())
 			row.setCrc(pm.computeRowSignature(row, bparams));
 		bool row_has_changed = row.changed()
-			|| rowSlice == bv_->lastRowSlice();
+			|| bv_->hadHorizScrollOffset(text_, pit, row.pos());
 
 		// Take this opportunity to spellcheck the row contents.
 		if (row_has_changed && pi.do_spellcheck && lyxrc.spellcheck_continuously) {
-- 
2.39.2