4 * This file is part of LyX, the document processor.
5 * Licence details can be found in the file COPYING.
7 * \author Matthias Ettrich
8 * \author Lars Gullik Bjønnes
10 * Full author contact details are available in file CREDITS.
12 * Metrics for an on-screen text row.
19 #include "Dimension.h"
22 #include "support/docstring.h"
23 #include "support/types.h"
33 * An on-screen row of text. A paragraph is broken into a RowList for
34 * display. Each Row contains a tokenized description of the contents
39 // Possible types of row elements
41 // a string of character
44 * Something (completion, end-of-par marker)
45 * that occupies space one screen but does not
46 * correspond to any paragraph contents
51 // Some spacing described by its width, not a string
56 * One element of a Row. It has a set of attributes that can be used
57 * by other methods that need to parse the Row contents.
60 Element(Type const t, pos_type p, Font const & f, Change const & ch)
61 : type(t), pos(p), endpos(p + 1), inset(0),
62 extra(0), font(f), change(ch), final(false) {}
64 // Return total width of element, including separator overhead
65 // FIXME: Cache this value or the number of separators?
66 double full_width() const { return dim.wid + extra * countSeparators(); }
67 // Return the number of separator in the element (only STRING type)
68 int countSeparators() const;
70 /** Return position in pixels (from the left) of position
71 * \param i in the row element.
73 double pos2x(pos_type const i) const;
74 /** Return character position that is the closest to
75 * pixel position \param x. The value \param x is
76 * adjusted to the actual pixel position.
78 pos_type x2pos(int &x) const;
79 /** Break the element if possible, so that its width is less
80 * than \param w. Returns true on success. When \param force
81 * is true, the string is cut at any place, other wise it
82 * respects the row breaking rules of characters.
84 bool breakAt(int w, bool force);
86 // Returns the position on left side of the element.
87 pos_type left_pos() const;
88 // Returns the position on right side of the element.
89 pos_type right_pos() const;
92 bool isRTL() const { return font.isVisibleRightToLeft(); }
93 // This is true for virtual elements.
94 // Note that we do not use the type here. The two definitions
95 // should be equivalent
96 bool isVirtual() const { return pos == endpos; }
98 // The kind of row element
100 // position of the element in the paragraph
102 // first position after the element in the paragraph
104 // The dimension of the chunk (does not contains the
105 // separator correction)
108 // Non-zero only if element is an inset
111 // Only non-null for justified rows
114 // Non-empty if element is a string or is virtual
120 // is it possible to add contents to this element?
123 friend std::ostream & operator<<(std::ostream & os, Element const & row);
130 bool changed() const { return changed_; }
132 void setChanged(bool c) { changed_ = c; }
134 void setCrc(size_type crc) const;
135 /// Set the selection begin and end.
137 * This is const because we update the selection status only at draw()
140 void setSelection(pos_type sel_beg, pos_type sel_end) const;
142 bool selection() const;
143 /// Set the selection begin and end and whether the left and/or right
144 /// margins are selected.
145 void setSelectionAndMargins(DocIterator const & beg,
146 DocIterator const & end) const;
149 void pit(pit_type p) { pit_ = p; }
151 pit_type pit() const { return pit_; }
153 void pos(pos_type p) { pos_ = p; }
155 pos_type pos() const { return pos_; }
157 void endpos(pos_type p) { end_ = p; }
159 pos_type endpos() const { return end_; }
161 void right_boundary(bool b) { right_boundary_ = b; }
163 bool right_boundary() const { return right_boundary_; }
166 Dimension const & dimension() const { return dim_; }
168 Dimension & dimension() { return dim_; }
170 int height() const { return dim_.height(); }
171 /// The width of the row, including the left margin, but not the right one.
172 int width() const { return dim_.wid; }
174 int ascent() const { return dim_.asc; }
176 int descent() const { return dim_.des; }
178 /// The offset of the left-most cursor position on the row
180 /// The offset of the right-most cursor position on the row
183 // Return the number of separators in the row
184 int countSeparators() const;
185 // Set the extra spacing for every separator in STRING elements
186 void setSeparatorExtraWidth(double w);
189 void add(pos_type pos, Inset const * ins, Dimension const & dim,
190 Font const & f, Change const & ch);
192 void add(pos_type pos, char_type const c,
193 Font const & f, Change const & ch);
195 void addVirtual(pos_type pos, docstring const & s,
196 Font const & f, Change const & ch);
198 void addSpace(pos_type pos, int width, Font const & f, Change const & ch);
201 typedef std::vector<Element> Elements;
203 typedef Elements::iterator iterator;
205 typedef Elements::const_iterator const_iterator;
207 iterator begin() { return elements_.begin(); }
209 iterator end() { return elements_.end(); }
211 const_iterator begin() const { return elements_.begin(); }
213 const_iterator end() const { return elements_.end(); }
216 bool empty() const { return elements_.empty(); }
218 Element & front() { return elements_.front(); }
220 Element const & front() const { return elements_.front(); }
222 Element & back() { return elements_.back(); }
224 Element const & back() const { return elements_.back(); }
225 /// remove last element
227 /// remove all row elements
228 void clear() { elements_.clear(); }
230 * if row width is too large, remove all elements after last
231 * separator and update endpos if necessary. If all that
232 * remains is a large word, cut it to \param width.
233 * \param body_pos minimum amount of text to keep.
234 * \param width maximum width of the row
235 * \return true if the row has been shortened.
237 bool shortenIfNeeded(pos_type const body_pos, int const width);
240 * If last element of the row is a string, compute its width
246 * Find sequences of right-to-left elements and reverse them.
247 * This should be called once the row is completely built.
249 void reverseRTL(bool rtl_par);
251 friend std::ostream & operator<<(std::ostream & os, Row const & row);
253 /// additional width for separators in justified rows (i.e. space)
255 /// width of hfills in the label
257 /// the left margin position of the row
259 /// the right margin of the row
262 mutable pos_type sel_beg;
264 mutable pos_type sel_end;
266 mutable bool begin_margin_sel;
268 mutable bool end_margin_sel;
271 /// Decides whether the margin is selected.
273 * \param margin_begin
277 bool isMarginSelected(bool left_margin, DocIterator const & beg,
278 DocIterator const & end) const;
281 * Returns true if a char or string with font \c f and change
282 * type \c ch can be added to the current last element of the
285 bool sameString(Font const & f, Change const & ch) const;
290 /// has the Row appearance changed since last drawing?
291 mutable bool changed_;
292 /// CRC of row contents.
293 mutable size_type crc_;
294 /// Index of the paragraph that contains this row
296 /// first pos covered by this row
298 /// one behind last pos covered by this row
300 // Is there is a boundary at the end of the row (display inset...)
301 bool right_boundary_;