lyx_mirror/src/Row.h
2014-07-08 21:30:06 +02:00

297 lines
7.4 KiB
C++

// -*- C++ -*-
/**
* \file Row.h
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author Matthias Ettrich
* \author Lars Gullik Bjønnes
*
* Full author contact details are available in file CREDITS.
*
* Metrics for an on-screen text row.
*/
#ifndef ROW_H
#define ROW_H
#include "Changes.h"
#include "Dimension.h"
#include "Font.h"
#include "support/docstring.h"
#include "support/types.h"
#include <vector>
namespace lyx {
class DocIterator;
class Inset;
/**
* FIXME: Change Row object to operate only on integers and not doubles.
*
* This use of double is only useful to distribute the extra
* horizontal space between separators in justified text. If we do
* integer arithmetic, then it is possible to have two groups of
* separators, with size s or s+1. Then strings can be drawn without
* cutting at separators in justfied text, as it is done in
* non-justified text. This will improve performance.
*/
/**
* An on-screen row of text. A paragraph is broken into a RowList for
* display. Each Row contains a tokenized description of the contents
* of the line.
*/
class Row {
public:
// Possible types of row elements
enum Type {
// a string of character
STRING,
/**
* Something (completion, end-of-par marker)
* that occupies space one screen but does not
* correspond to any paragraph contents
*/
VIRTUAL,
// A stretchable space, basically
SEPARATOR,
// An inset
INSET,
// Some spacing described by its width, not a string
SPACE
};
/**
* One element of a Row. It has a set of attributes that can be used
* by other methods that need to parse the Row contents.
*/
struct Element {
Element(Type const t, pos_type p, Font const & f, Change const & ch)
: type(t), pos(p), endpos(p + 1), inset(0),
extra(0), font(f), change(ch), final(false) {}
// Return total width of element, including separator overhead
double width() const { return dim.wid + extra; };
/** Return position in pixels (from the left) of position
* \param i in the row element.
*/
double pos2x(pos_type const i) const;
/** Return character position that is the closest to
* pixel position \param x. The value \param x is
* adjusted to the actual pixel position.
*/
pos_type x2pos(double &x) const;
/** Break the element if possible, so that its width is
* less then \param w. Returns true on success.
*/
bool breakAt(double w);
// Returns the position on left side of the element.
pos_type left_pos() const;
// Returns the position on right side of the element.
pos_type right_pos() const;
// The kind of row element
Type type;
// position of the element in the paragraph
pos_type pos;
// first position after the element in the paragraph
pos_type endpos;
// The dimension of the chunk (does not contains the
// separator correction)
Dimension dim;
// Non-zero only if element is an inset
Inset const * inset;
// Only non-null for separator elements
double extra;
// Non-empty if element is a string or separator
docstring str;
//
Font font;
//
Change change;
// is it possible to add contents to this element?
bool final;
friend std::ostream & operator<<(std::ostream & os, Element const & row);
};
///
Row();
///
bool changed() const { return changed_; }
///
void setChanged(bool c) { changed_ = c; }
///
void setCrc(size_type crc) const;
/// Set the selection begin and end.
/**
* This is const because we update the selection status only at draw()
* time.
*/
void setSelection(pos_type sel_beg, pos_type sel_end) const;
///
bool selection() const;
/// Set the selection begin and end and whether the left and/or right
/// margins are selected.
void setSelectionAndMargins(DocIterator const & beg,
DocIterator const & end) const;
///
void pos(pos_type p) { pos_ = p; }
///
pos_type pos() const { return pos_; }
///
void endpos(pos_type p) { end_ = p; }
///
pos_type endpos() const { return end_; }
///
void right_boundary(bool b) { right_boundary_ = b; }
///
bool right_boundary() const { return right_boundary_; }
///
Dimension const & dimension() const { return dim_; }
///
Dimension & dimension() { return dim_; }
///
int height() const { return dim_.height(); }
///
int width() const { return dim_.wid; }
///
int ascent() const { return dim_.asc; }
///
int descent() const { return dim_.des; }
///
void add(pos_type pos, Inset const * ins, Dimension const & dim,
Font const & f, Change const & ch);
///
void add(pos_type pos, char_type const c,
Font const & f, Change const & ch);
///
void addVirtual(pos_type pos, docstring const & s,
Font const & f, Change const & ch);
///
void addSeparator(pos_type pos, char_type const c,
Font const & f, Change const & ch);
///
void addSpace(pos_type pos, int width, Font const & f, Change const & ch);
///
typedef std::vector<Element> Elements;
///
typedef Elements::iterator iterator;
///
typedef Elements::const_iterator const_iterator;
///
iterator begin() { return elements_.begin(); }
///
iterator end() { return elements_.end(); }
///
const_iterator begin() const { return elements_.begin(); }
///
const_iterator end() const { return elements_.end(); }
///
bool empty() const { return elements_.empty(); }
///
Element & front() { return elements_.front(); }
///
Element const & front() const { return elements_.front(); }
///
Element & back() { return elements_.back(); }
///
Element const & back() const { return elements_.back(); }
/// remove last element
void pop_back();
/// remove all row elements
void clear() { elements_.clear(); }
/**
* if row width is too large, remove all elements after last
* separator and update endpos if necessary. If all that
* remains is a large word, cut it to \param width.
* \param body_pos minimum amount of text to keep.
* \param width maximum width of the row
*/
void shortenIfNeeded(pos_type const body_pos, int const width);
/**
* If last element of the row is a string, compute its width
* and mark it final.
*/
void finalizeLast();
/**
* Find sequences of right-to-left elements and reverse them.
* This should be called once the row is completely built.
*/
void reverseRTL(bool rtl_par);
friend std::ostream & operator<<(std::ostream & os, Row const & row);
/// width of a separator (i.e. space)
double separator;
/// width of hfills in the label
double label_hfill;
/// the x position of the row (left margin)
double x;
/// the right margin of the row
int right_margin;
///
mutable pos_type sel_beg;
///
mutable pos_type sel_end;
///
mutable bool begin_margin_sel;
///
mutable bool end_margin_sel;
private:
/// Decides whether the margin is selected.
/**
* \param margin_begin
* \param beg
* \param end
*/
bool isMarginSelected(bool left_margin, DocIterator const & beg,
DocIterator const & end) const;
/**
* Returns true if a char or string with font \c f and change
* type \c ch can be added to the current last element of the
* row.
*/
bool sameString(Font const & f, Change const & ch) const;
///
Elements elements_;
/// has the Row appearance changed since last drawing?
mutable bool changed_;
/// CRC of row contents.
mutable size_type crc_;
/// first pos covered by this row
pos_type pos_;
/// one behind last pos covered by this row
pos_type end_;
// Is there is a boundary at the end of the row (display inset...)
bool right_boundary_;
/// Row dimension.
Dimension dim_;
};
} // namespace lyx
#endif