X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Flyxcursor.h;h=8c78d9f5d463e1be81a3994486ed913cf13c08bd;hb=0ba59ef037642f4de07669128355fac762b04746;hp=60ad1e0bfbe4386b2fc85d2dd55c3fc1703c4f4a;hpb=797d87b4513088a66b17c7ac653b84e36ea80458;p=lyx.git

diff --git a/src/lyxcursor.h b/src/lyxcursor.h
index 60ad1e0bfb..8c78d9f5d4 100644
--- a/src/lyxcursor.h
+++ b/src/lyxcursor.h
@@ -1,13 +1,11 @@
 // -*- C++ -*-
-/* This file is part of
- * ====================================================== 
- * 
- *           LyX, The Document Processor
- * 	 
- *           Copyright 1995 Matthias Ettrich
- *           Copyright 1995-2000 The LyX Team.
+/**
+ * \file lyxcursor.h
+ * Copyright 1995-2001 the LyX Team
+ * Read the file COPYING
  *
- * ====================================================== */
+ * \author Matthias Ettrich
+ */
 
 #ifndef LYXCURSOR_H
 #define LYXCURSOR_H
@@ -16,64 +14,128 @@
 #pragma interface
 #endif
 
-#include "lyxparagraph.h"
+#include "support/types.h"
 
-struct Row;
+class Paragraph;
+class Row;
 
-/** All these variables should be explained. Matthias?
+/** 
+ * The cursor class describes the position of a cursor within a document.
+ * Several cursors exist within LyX; for example, when locking an inset,
+ * the position of the cursor in the containing inset is stored.
+ *
+ * FIXME: true ?
  */
 class LyXCursor {
 public:
-	///
-	void par(LyXParagraph * p);
-	///
-	LyXParagraph * par();
-	///
-	LyXParagraph * par() const;
-	///
-	void pos(LyXParagraph::size_type p);
-	///
-	LyXParagraph::size_type pos() const;
-	///
+	LyXCursor();
+	/// set the paragraph that contains this cursor
+	void par(Paragraph * p);
+	/// return the paragraph this cursor is in
+	Paragraph * par() const;
+	/// set the position within the paragraph
+	void pos(lyx::pos_type p);
+	/// return the position within the paragraph
+	lyx::pos_type pos() const;
+	/// FIXME
 	void boundary(bool b);
-	///
+	/// FIXME
 	bool boundary() const;
-	///
+	/// set the x position in pixels
 	void x(int i);
-	///
+	/// return the x position in pixels
 	int x() const;
-	///
+	/// set the stored next-line position when at the end of a row
+	void ix(int i);
+	/**
+	 * Return the x position of the start of the next row, when this
+	 * cursor is at the end of the previous row, for insets that take
+	 * a full row.
+	 *
+	 * FIXME: explain why we need this ?
+	 */
+	int ix() const;
+	/// set the cached x position
 	void x_fix(int i);
-	///
+	/**
+	 * Return the cached x position of the cursor. This is used for when
+	 * we have text like :
+	 *
+	 * blah blah blah blah| blah blah blah
+	 * blah blah blah
+	 * blah blah blah blah blah blah
+	 *
+	 * When we move onto row 3, we would like to be vertically aligned
+	 * with where we were in row 1, despite the fact that row 2 is 
+	 * shorter than x()
+	 */
 	int x_fix() const;
-	///
-	void y(unsigned long i);
-	///
-	unsigned long y() const;
-	///
+	/// set the y position in pixels
+	void y(int i);
+	/// return the y position in pixels
+	int y() const;
+	/// set the stored next-line y position when at the end of a row
+	void iy(int i);
+	/**
+	 * Return the y position of the start of the next row, when this
+	 * cursor is at the end of the previous row, for insets that take
+	 * a full row.
+	 *
+	 * FIXME: explain why we need this ? especially for y...
+	 */
+	int iy() const;
+	/// set the row of the paragraph the cursor is in
 	void row(Row * r);
-	///
-	Row * row();
-	///
+	/// return the row of the paragraph this cursor is in
 	Row * row() const;
+	/// set the stored next row
+	void irow(Row * r);
+	/**
+	 * Return the next row, when this
+	 * cursor is at the end of the previous row, for insets that take
+	 * a full row.
+	 *
+	 * FIXME: explain why we need this ? especially for y...
+	 */
+	Row * irow() const;
 private:
 	/// The paragraph the cursor is in.
-	LyXParagraph * par_;
+	Paragraph * par_;
 	/// The position inside the paragraph
-	LyXParagraph::size_type pos_;
-	///
+	lyx::pos_type pos_;
+	/**
+	 * When the cursor position is i, is the cursor is after the i-th char
+	 * or before the i+1-th char ? Normally, these two interpretations are
+	 * equivalent, except when the fonts of the i-th and i+1-th char
+	 * differ.
+	 * We use boundary_ to distinguish between the two options:
+	 * If boundary_=true, then the cursor is after the i-th char
+	 * and if boundary_=false, then the cursor is before the i+1-th char.
+	 *
+	 * We currently use the boundary only when the language direction of
+	 * the i-th char is different than the one of the i+1-th char.
+	 * In this case it is important to distinguish between the two
+	 * cursor interpretations, in order to give a reasonable behavior to
+	 * the user.
+	 */
 	bool boundary_;
-	///
+	/// the pixel x position
 	int x_;
-	///
+	/// the stored next-row x position 
+	int ix_;
+	/// the cached x position
 	int x_fix_;
-	///
-	unsigned long y_;
-	///
+	/// the pixel y position
+	int y_;
+	/// the stored next-row y position
+	int iy_;
+	/// the containing row
 	Row * row_;
+	/// the containing row for the next line 
+	Row * irow_;
 };
 
-///
+/// these three dictate the others
 inline
 bool operator==(LyXCursor const & a, LyXCursor const & b)
 {
@@ -82,11 +144,36 @@ bool operator==(LyXCursor const & a, LyXCursor const & b)
 		&& a.boundary() == b.boundary();
 }
 
-///
 inline
 bool operator!=(LyXCursor const & a, LyXCursor const & b)
 {
 	return !(a == b);
 }
 
-#endif
+/// only compares y() and pos(). Can this be done in another way?
+inline
+bool operator<(LyXCursor const & a, LyXCursor const & b)
+{
+	return (a.y() < b.y() && a.pos() < b.pos());
+}
+
+inline
+bool operator>(LyXCursor const & a, LyXCursor const & b)
+{
+	return b < a;
+}
+
+inline
+bool operator>=(LyXCursor const & a, LyXCursor const & b)
+{
+	return !(a < b);
+}
+
+
+inline
+bool operator<=(LyXCursor const & a, LyXCursor const & b)
+{
+	return !(a > b);
+}
+
+#endif // LYXCURSOR_H