X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2FLength.h;h=2a8f0642108602fb70c8f01195f47fff31e4322d;hb=e335c764b47f8154973be212b446d9c13972cdf3;hp=c6e32c3431e94b570681bf4bd38ba711213881a4;hpb=bd5cccbb3446ac61ffd78a98f34b188a4be4307b;p=lyx.git

diff --git a/src/Length.h b/src/Length.h
index c6e32c3431..2a8f064210 100644
--- a/src/Length.h
+++ b/src/Length.h
@@ -20,6 +20,8 @@
 
 namespace lyx {
 
+class MetricsBase;
+
 // Solaris/x86 version 9 and earlier define these
 #undef PC
 #undef SP
@@ -38,24 +40,24 @@ class Length {
 public:
 	/// length units
 	enum UNIT {
-		SP, ///< Scaled point (65536sp = 1pt) TeX's smallest unit.
-		PT, ///< Point = 1/72.27in = 0.351mm
 		BP, ///< Big point (72bp = 1in), also PostScript point
-		DD, ///< Didot point = 1/72 of a French inch, = 0.376mm
-		MM, ///< Millimeter = 2.845pt
-		PC, ///< Pica = 12pt = 4.218mm
 		CC, ///< Cicero = 12dd = 4.531mm
 		CM, ///< Centimeter = 10mm = 2.371pc
-		IN, ///< Inch = 25.4mm = 72.27pt = 6.022pc
-		EX, ///< Height of a small "x" for the current font.
+		DD, ///< Didot point = 1/72 of a French inch, = 0.376mm
 		EM, ///< Width of capital "M" in current font.
+		EX, ///< Height of a small "x" for the current font.
+		IN, ///< Inch = 25.4mm = 72.27pt = 6.022pc
+		MM, ///< Millimeter = 2.845pt
 		MU, ///< Math unit (18mu = 1em) for positioning in math mode
+		PC, ///< Pica = 12pt = 4.218mm
+		PT, ///< Point = 1/72.27in = 0.351mm
+		SP, ///< Scaled point (65536sp = 1pt) TeX's smallest unit.
 		PTW, //< Percent of TextWidth
 		PCW, //< Percent of ColumnWidth
 		PPW, //< Percent of PageWidth
 		PLW, //< Percent of LineWidth
-		PTH, //< Percent of TextHeight		// Herbert 2002-05-16
-		PPH, //< Percent of PaperHeight		// Herbert 2002-05-16
+		PTH, //< Percent of TextHeight          // Herbert 2002-05-16
+		PPH, //< Percent of PaperHeight         // Herbert 2002-05-16
 		UNIT_NONE ///< no unit
 	};
 
@@ -67,8 +69,6 @@ public:
 	/// "data" must be a decimal number, followed by a unit
 	explicit Length(std::string const & data);
 
-	///
-	void swap(Length & rhs);
 	///
 	double value() const;
 	///
@@ -89,9 +89,20 @@ public:
 	std::string const asLatexString() const;
 	/// return string representation for HTML
 	std::string const asHTMLString() const;
-	/// return the on-screen size of this length
+	/** return the on-screen size of this length.
+	 *
+	 *	If the second argument is not provided, then the unit EM will
+	 *	only be approximated. It is better if possible to use
+	 *	FontMetrics::em() to get this value.
+	 */
 	int inPixels(int text_width, int em_width = 0) const;
+	/** return the on-screen size of this length
+	 *
+	 *  This version of the function uses the right EM definition.
+	 */
+	int inPixels(MetricsBase const &) const;
 	/// return the value in Big Postscript points.
+	/// Caution: Inaccurate for em, ex, mu and percent units.
 	int inBP() const;
 
 	/// return the default unit (centimeter or inch)
@@ -100,6 +111,8 @@ public:
 	friend bool isValidLength(std::string const & data, Length * result);
 
 private:
+	/// Convert value to inch for text width and em width given in inch
+	double inInch(double text_width, double em_width) const;
 	///
 	double val_;
 	///