Replace the hardcoded TEXT_TO_INSET_OFFSET by tunable values

The basic value is Inset::textOffset(BufferView*), which can in theory
change with the BufferView zoom and dpi. It is hardcoded to 4 for now.

Moreover, we introduce the virtual inset methods
(top|bottom|left|right)Offset, which can be tweaked for each inset.

No change intended (for now).

src/RowPainter.cpp

@@ -479,10 +479,10 @@ void RowPainter::paintLast() const
 		int x = 0;
 		if (row_.isRTL()) {
 			int const normal_x = nestMargin() + changebarMargin();
-			x = min(normal_x, row_.left_margin - size - Inset::TEXT_TO_INSET_OFFSET);
+			x = min(normal_x, row_.left_margin - size - Inset::textOffset(pi_.base.bv));
 		} else {
 			int const normal_x = tm_.width() - row_.right_margin
-				- size - Inset::TEXT_TO_INSET_OFFSET;
+				- size - Inset::textOffset(pi_.base.bv);
 			x = max(normal_x, row_.width());
 		}
 

src/TextMetrics.cpp

@@ -1933,9 +1933,9 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type const pit, int const
 			// the begining/end of row. However, it will not work if
 			// the caret has a ridiculous width like 6. (see ticket
 			// #10797)
-			pi.pain.fillRectangle(max(row_x, 0) - Inset::TEXT_TO_INSET_OFFSET,
+			pi.pain.fillRectangle(max(row_x, 0) - Inset::textOffset(pi.base.bv),
 			                      y - row.ascent(),
-			                      width() + 2 * Inset::TEXT_TO_INSET_OFFSET,
+			                      width() + 2 * Inset::textOffset(pi.base.bv),
 			                      row.height(), pi.background_color);
 		}
 

src/insets/Inset.h

@@ -202,6 +202,17 @@ public:
 	/// https://www.mail-archive.com/lyx-devel@lists.lyx.org/msg199001.html
 	virtual Inset * editXY(Cursor & cur, int x, int y);
 
+	/// The default margin inside text insets
+	static int textOffset(BufferView const *) { return 4; }
+	///
+	virtual int topOffset(BufferView const *bv) const { return textOffset(bv); }
+	///
+	virtual int bottomOffset(BufferView const *bv) const { return textOffset(bv); }
+	///
+	virtual int leftOffset(BufferView const *bv) const { return textOffset(bv); }
+	///
+	virtual int rightOffset(BufferView const *bv) const { return textOffset(bv); }
+
 	/// compute the size of the object returned in dim
 	virtual void metrics(MetricsInfo & mi, Dimension & dim) const = 0;
 	/// draw inset and update (xo, yo)-cache
@@ -610,8 +621,6 @@ public:
 	virtual ColorCode backgroundColor(PainterInfo const &) const;
 	///
 	virtual ColorCode labelColor() const;
-	//
-	enum { TEXT_TO_INSET_OFFSET = 4 };
 
 	/// Determine the action of backspace and delete: do we select instead of
 	/// deleting if not already selected?

src/insets/InsetCaption.cpp

@@ -114,7 +114,7 @@ void InsetCaption::metrics(MetricsInfo & mi, Dimension & dim) const
 	mi.base.font = mi.base.bv->buffer().params().getFont().fontInfo();
 	labelwidth_ = theFontMetrics(mi.base.font).width(full_label_);
 	// add some space to separate the label from the inset text
-	labelwidth_ += 2 * TEXT_TO_INSET_OFFSET;
+	labelwidth_ += leftOffset(mi.base.bv) + rightOffset(mi.base.bv);
 	dim.wid = labelwidth_;
 	Dimension textdim;
 	// Correct for button and label width
@@ -131,8 +131,8 @@ void InsetCaption::metrics(MetricsInfo & mi, Dimension & dim) const
 void InsetCaption::drawBackground(PainterInfo & pi, int x, int y) const
 {
 	TextMetrics & tm = pi.base.bv->textMetrics(&text());
-	int const h = tm.height() + 2 * TEXT_TO_INSET_OFFSET;
+	int const h = tm.height() + topOffset(pi.base.bv) + bottomOffset(pi.base.bv);
-	int const yy = y - TEXT_TO_INSET_OFFSET - tm.ascent();
+	int const yy = y - topOffset(pi.base.bv) - tm.ascent();
 	pi.pain.fillRectangle(x, yy, labelwidth_, h, pi.backgroundColor(this));
 }
 
@@ -150,7 +150,7 @@ void InsetCaption::draw(PainterInfo & pi, int x, int y) const
 	FontInfo tmpfont = pi.base.font;
 	pi.base.font = pi.base.bv->buffer().params().getFont().fontInfo();
 	pi.base.font.setColor(pi.textColor(pi.base.font.color()).baseColor);
-	int const xx = x + TEXT_TO_INSET_OFFSET;
+	int const xx = x + leftOffset(pi.base.bv);
 	pi.pain.text(xx, y, full_label_, pi.base.font);
 	InsetText::draw(pi, x + labelwidth_, y);
 	pi.base.font = tmpfont;

src/insets/InsetCollapsible.cpp

@@ -164,7 +164,7 @@ Dimension InsetCollapsible::dimensionCollapsed(BufferView const & bv) const
 	FontInfo labelfont(getLabelfont());
 	labelfont.realize(sane_font);
 	theFontMetrics(labelfont).buttonText(
-		buttonLabel(bv), TEXT_TO_INSET_OFFSET, dim.wid, dim.asc, dim.des);
+		buttonLabel(bv), Inset::textOffset(&bv), dim.wid, dim.asc, dim.des);
 	return dim;
 }
 
@@ -221,7 +221,7 @@ void InsetCollapsible::metrics(MetricsInfo & mi, Dimension & dim) const
 				dim.des = max(dim.des - textdim.asc + dim.asc, textdim.des);
 				dim.asc = textdim.asc;
 			} else {
-				dim.des += textdim.height() + TEXT_TO_INSET_OFFSET;
+				dim.des += textdim.height() + topOffset(mi.base.bv);
 				dim.wid = max(dim.wid, textdim.wid);
 			}
 		}
@@ -264,7 +264,7 @@ void InsetCollapsible::draw(PainterInfo & pi, int x, int y) const
 		labelfont.realize(pi.base.font);
 		pi.pain.buttonText(x, y, buttonLabel(bv), labelfont,
 		                   view_[&bv].mouse_hover_ ? Color_buttonhoverbg : Color_buttonbg,
-		                   Color_buttonframe, TEXT_TO_INSET_OFFSET);
+		                   Color_buttonframe, Inset::textOffset(pi.base.bv));
 		// Draw the change tracking cue on the label, unless RowPainter already
 		// takes care of it.
 		if (canPaintChange(bv))
@@ -325,8 +325,8 @@ void InsetCollapsible::draw(PainterInfo & pi, int x, int y) const
 		// Colour the frame according to the change type. (Like for tables.)
 		Color colour = pi.change.changed() ? pi.change.color()
 		                                    : Color_foreground;
-		const int xx1 = x + TEXT_TO_INSET_OFFSET - 1;
+		const int xx1 = x + leftOffset(pi.base.bv) - 1;
-		const int xx2 = x + textdim.wid - TEXT_TO_INSET_OFFSET + 1;
+		const int xx2 = x + textdim.wid - rightOffset(pi.base.bv) + 1;
 		pi.pain.line(xx1, y + desc - 4,
 		             xx1, y + desc, colour);
 		if (status_ == Open)

src/insets/InsetIPA.cpp

@@ -184,8 +184,8 @@ void InsetIPA::metrics(MetricsInfo & mi, Dimension & dim) const
 		dim.wid = max(dim.wid, 4);
 		dim.asc = max(dim.asc, 4);
 
-		dim.asc += TEXT_TO_INSET_OFFSET;
+		dim.asc += topOffset(mi.base.bv);
-		dim.des += TEXT_TO_INSET_OFFSET;
+		dim.des += bottomOffset(mi.base.bv);
 		// insert a one pixel gap
 		dim.wid += 1;
 		Dimension dim_dummy;

src/insets/InsetPhantom.cpp

@@ -194,10 +194,10 @@ void InsetPhantom::draw(PainterInfo & pi, int x, int y) const
 		//       |   |        |   |
 		//      x1  x2       x3  x4
 
-		x = x + TEXT_TO_INSET_OFFSET;
+		x += leftOffset(pi.base.bv);
 		int const x1 = x;
 		int const x2 = x + arrow_size;
-		int const x4 = x + dim.wid - 2 * TEXT_TO_INSET_OFFSET;
+		int const x4 = x + dim.wid - leftOffset(pi.base.bv) - rightOffset(pi.base.bv);
 		int const x3 = x4 - arrow_size;
 
 		int const y2 = y + (dim.des - dim.asc) / 2;

src/insets/InsetPreview.cpp

@@ -170,8 +170,8 @@ void InsetPreview::metrics(MetricsInfo & mi, Dimension & dim) const
 		dim.wid = max(dim.wid, 4);
 		dim.asc = max(dim.asc, 4);
 
-		dim.asc += TEXT_TO_INSET_OFFSET;
+		dim.asc += topOffset(mi.base.bv);
-		dim.des += TEXT_TO_INSET_OFFSET;
+		dim.des += bottomOffset(mi.base.bv);
 		// insert a one pixel gap
 		dim.wid += 1;
 		Dimension dim_dummy;

src/insets/InsetTabular.cpp

@@ -4180,10 +4180,11 @@ docstring InsetTableCell::xhtml(XHTMLStream & xs, OutputParams const & rp) const
 void InsetTableCell::metrics(MetricsInfo & mi, Dimension & dim) const
 {
 	TextMetrics & tm = mi.base.bv->textMetrics(&text());
+	int const horiz_offset = leftOffset(mi.base.bv) + rightOffset(mi.base.bv);
 
 	// Hand font through to contained lyxtext:
 	tm.font_.fontInfo() = mi.base.font;
-	mi.base.textwidth -= 2 * TEXT_TO_INSET_OFFSET;
+	mi.base.textwidth -= horiz_offset;
 
 	// This can happen when a layout has a left and right margin,
 	// and the view is made very narrow. We can't do better than
@@ -4197,10 +4198,10 @@ void InsetTableCell::metrics(MetricsInfo & mi, Dimension & dim) const
 		tm.metrics(mi, dim, mi.base.textwidth, false);
 	else
 		tm.metrics(mi, dim, 0, false);
-	mi.base.textwidth += 2 * TEXT_TO_INSET_OFFSET;
+	mi.base.textwidth += horiz_offset;
-	dim.asc += TEXT_TO_INSET_OFFSET;
+	dim.asc += topOffset(mi.base.bv);
-	dim.des += TEXT_TO_INSET_OFFSET;
+	dim.des += bottomOffset(mi.base.bv);
-	dim.wid += 2 * TEXT_TO_INSET_OFFSET;
+	dim.wid += horiz_offset;
 }
 
 
@@ -4391,9 +4392,9 @@ void InsetTabular::metrics(MetricsInfo & mi, Dimension & dim) const
 			tabular.cell_info[r][c].decimal_width = decimal_width;
 
 			// with LYX_VALIGN_BOTTOM the descent is relative to the last par
-			// = descent of text in last par + TEXT_TO_INSET_OFFSET:
+			// = descent of text in last par + bottomOffset:
 			int const lastpardes = tm.last().second->descent()
-				+ TEXT_TO_INSET_OFFSET;
+				+ bottomOffset(mi.base.bv);
 			int offset = 0;
 			switch (tabular.getVAlignment(cell)) {
 				case Tabular::LYX_VALIGN_TOP:

src/insets/InsetText.cpp

@@ -141,9 +141,9 @@ Dimension const InsetText::dimensionHelper(BufferView const & bv) const
 {
 	TextMetrics const & tm = bv.textMetrics(&text_);
 	Dimension dim = tm.dim();
-	dim.wid += 2 * TEXT_TO_INSET_OFFSET;
+	dim.wid += leftOffset(&bv) + rightOffset(&bv);
-	dim.des += TEXT_TO_INSET_OFFSET;
+	dim.des += bottomOffset(&bv);
-	dim.asc += TEXT_TO_INSET_OFFSET;
+	dim.asc += topOffset(&bv);
 	return dim;
 }
 
@@ -190,9 +190,11 @@ void InsetText::metrics(MetricsInfo & mi, Dimension & dim) const
 
 	//lyxerr << "InsetText::metrics: width: " << mi.base.textwidth << endl;
 
+	int const horiz_offset = leftOffset(mi.base.bv) + rightOffset(mi.base.bv);
+
 	// Hand font through to contained lyxtext:
 	tm.font_.fontInfo() = mi.base.font;
-	mi.base.textwidth -= 2 * TEXT_TO_INSET_OFFSET;
+	mi.base.textwidth -= horiz_offset;
 
 	// This can happen when a layout has a left and right margin,
 	// and the view is made very narrow. We can't do better than
@@ -204,10 +206,10 @@ void InsetText::metrics(MetricsInfo & mi, Dimension & dim) const
 		tm.metrics(mi, dim, mi.base.textwidth);
 	else
 		tm.metrics(mi, dim);
-	mi.base.textwidth += 2 * TEXT_TO_INSET_OFFSET;
+	mi.base.textwidth += horiz_offset;
-	dim.asc += TEXT_TO_INSET_OFFSET;
+	dim.asc += topOffset(mi.base.bv);
-	dim.des += TEXT_TO_INSET_OFFSET;
+	dim.des += bottomOffset(mi.base.bv);
-	dim.wid += 2 * TEXT_TO_INSET_OFFSET;
+	dim.wid += horiz_offset;
 }
 
 
@@ -215,10 +217,11 @@ void InsetText::draw(PainterInfo & pi, int x, int y) const
 {
 	TextMetrics & tm = pi.base.bv->textMetrics(&text_);
 
-	int const w = tm.width() + TEXT_TO_INSET_OFFSET;
+	int const horiz_offset = leftOffset(pi.base.bv) + rightOffset(pi.base.bv);
-	int const yframe = y - TEXT_TO_INSET_OFFSET - tm.ascent();
+	int const w = tm.width() + (horiz_offset - horiz_offset / 2);
-	int const h = tm.height() + 2 * TEXT_TO_INSET_OFFSET;
+	int const yframe = y - topOffset(pi.base.bv) - tm.ascent();
-	int const xframe = x + TEXT_TO_INSET_OFFSET / 2;
+	int const h = tm.height() + topOffset(pi.base.bv) + bottomOffset(pi.base.bv);
+	int const xframe = x + leftOffset(pi.base.bv) / 2;
 	bool change_drawn = false;
 	if (pi.full_repaint)
 			pi.pain.fillRectangle(xframe, yframe, w, h,
@@ -229,7 +232,7 @@ void InsetText::draw(PainterInfo & pi, int x, int y) const
 		                            pi.backgroundColor(this, false));
 		// The change tracking cue must not be inherited
 		Changer dummy2 = make_change(pi.change, Change());
-		tm.draw(pi, x + TEXT_TO_INSET_OFFSET, y);
+		tm.draw(pi, x + leftOffset(pi.base.bv), y);
 	}
 
 	if (drawFrame_) {
@@ -699,7 +702,7 @@ void InsetText::getArgs(otexstream & os, OutputParams const & runparams_in,
 void InsetText::cursorPos(BufferView const & bv,
 		CursorSlice const & sl, bool boundary, int & x, int & y) const
 {
-	x = bv.textMetrics(&text_).cursorX(sl, boundary) + TEXT_TO_INSET_OFFSET;
+	x = bv.textMetrics(&text_).cursorX(sl, boundary) + leftOffset(&bv);
 	y = bv.textMetrics(&text_).cursorY(sl, boundary);
 }
 

src/insets/RenderButton.cpp

@@ -47,7 +47,7 @@ void RenderButton::metrics(MetricsInfo & mi, Dimension & dim) const
 	font.decSize();
 	frontend::FontMetrics const & fm = theFontMetrics(font);
 
-	fm.buttonText(text_, Inset::TEXT_TO_INSET_OFFSET, dim.wid, dim.asc, dim.des);
+	fm.buttonText(text_, Inset::textOffset(mi.base.bv), dim.wid, dim.asc, dim.des);
 
 	dim_ = dim;
 }
@@ -63,11 +63,11 @@ void RenderButton::draw(PainterInfo & pi, int x, int y) const
 	if (editable_) {
 		pi.pain.buttonText(x, y, text_, font,
 		                   renderState() ? Color_buttonhoverbg : Color_buttonbg,
-		                   Color_buttonframe, Inset::TEXT_TO_INSET_OFFSET);
+		                   Color_buttonframe, Inset::textOffset(pi.base.bv));
 	} else {
 		pi.pain.buttonText(x, y, text_, font,
 		                   Color_commandbg, Color_commandframe,
-		                   Inset::TEXT_TO_INSET_OFFSET);
+		                   Inset::textOffset(pi.base.bv));
 	}
 }
 

src/insets/RenderGraphic.cpp

@@ -147,7 +147,7 @@ void RenderGraphic::metrics(MetricsInfo & mi, Dimension & dim) const
 
 	bool const image_ready = displayGraphic(params_) && readyToDisplay(loader_);
 	if (image_ready) {
-		dim.wid = loader_.image()->width() + 2 * Inset::TEXT_TO_INSET_OFFSET;
+		dim.wid = loader_.image()->width() + 2 * Inset::textOffset(mi.base.bv);
 		dim.asc = loader_.image()->height();
 		dim_ = dim;
 		return;
@@ -190,9 +190,9 @@ void RenderGraphic::draw(PainterInfo & pi, int x, int y) const
 {
 	// This will draw the graphics. If the graphics has not been
 	// loaded yet, we draw just a rectangle.
-	int const x1 = x + Inset::TEXT_TO_INSET_OFFSET;
+	int const x1 = x + Inset::textOffset(pi.base.bv);
 	int const y1 = y - dim_.asc;
-	int const w = dim_.wid - 2 * Inset::TEXT_TO_INSET_OFFSET;
+	int const w = dim_.wid - 2 * Inset::textOffset(pi.base.bv);
 	int const h = dim_.height();
 
 	if (displayGraphic(params_) && readyToDisplay(loader_))

src/insets/RenderPreview.cpp

@@ -166,7 +166,7 @@ void RenderPreview::draw(PainterInfo & pi, int x, int y) const
 		pi.pain.image(x, y - dim_.asc, dim_.wid, dim_.height(),
 			      *image);
 	} else {
-		int const offset = Inset::TEXT_TO_INSET_OFFSET;
+		int const offset = Inset::textOffset(pi.base.bv);
 
 		pi.pain.rectangle(x + offset,
 				  y - dim_.asc,