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 * FIXME: Change Row object to operate only on integers and not doubles.
35 * This use of double is only useful to distribute the extra
36 * horizontal space between separators in justified text. If we do
37 * integer arithmetic, then it is possible to have two groups of
38 * separators, with size s or s+1. Then strings can be drawn without
39 * cutting at separators in justfied text, as it is done in
40 * non-justified text. This will improve performance.
45 * An on-screen row of text. A paragraph is broken into a RowList for
46 * display. Each Row contains a tokenized description of the contents
51 // Possible types of row elements
53 // a string of character
56 * Something (completion, end-of-par marker)
57 * that occupies space one screen but does not
58 * correspond to any paragraph contents
61 // A stretchable space, basically
65 // Some spacing described by its width, not a string
70 * One element of a Row. It has a set of attributes that can be used
71 * by other methods that need to parse the Row contents.
74 Element(Type const t, pos_type p, Font const & f, Change const & ch)
75 : type(t), pos(p), endpos(p + 1), inset(0),
76 extra(0), font(f), change(ch), final(false) {}
78 // Return total width of element, including separator overhead
79 double full_width() const { return dim.wid + extra * countSeparators(); };
80 // Return the number of separator in the element (only STRING type)
81 int countSeparators() const;
83 /** Return position in pixels (from the left) of position
84 * \param i in the row element.
86 double pos2x(pos_type const i) const;
87 /** Return character position that is the closest to
88 * pixel position \param x. The value \param x is
89 * adjusted to the actual pixel position.
91 pos_type x2pos(int &x) const;
92 /** Break the element if possible, so that its width is less
93 * than \param w. Returns true on success. When \param force
94 * is true, the string is cut at any place, other wise it
95 * respects the row breaking rules of characters.
97 bool breakAt(int w, bool force);
99 // Returns the position on left side of the element.
100 pos_type left_pos() const;
101 // Returns the position on right side of the element.
102 pos_type right_pos() const;
104 // The kind of row element
106 // position of the element in the paragraph
108 // first position after the element in the paragraph
110 // The dimension of the chunk (does not contains the
111 // separator correction)
114 // Non-zero only if element is an inset
117 // Only non-null for separator elements
120 // Non-empty if element is a string or separator
126 // is it possible to add contents to this element?
129 friend std::ostream & operator<<(std::ostream & os, Element const & row);
136 bool changed() const { return changed_; }
138 void setChanged(bool c) { changed_ = c; }
140 void setCrc(size_type crc) const;
141 /// Set the selection begin and end.
143 * This is const because we update the selection status only at draw()
146 void setSelection(pos_type sel_beg, pos_type sel_end) const;
148 bool selection() const;
149 /// Set the selection begin and end and whether the left and/or right
150 /// margins are selected.
151 void setSelectionAndMargins(DocIterator const & beg,
152 DocIterator const & end) const;
155 void pos(pos_type p) { pos_ = p; }
157 pos_type pos() const { return pos_; }
159 void endpos(pos_type p) { end_ = p; }
161 pos_type endpos() const { return end_; }
163 void right_boundary(bool b) { right_boundary_ = b; }
165 bool right_boundary() const { return right_boundary_; }
168 Dimension const & dimension() const { return dim_; }
170 Dimension & dimension() { return dim_; }
172 int height() const { return dim_.height(); }
173 /// The width of the row, including the left margin, but not the right one.
174 int width() const { return dim_.wid; }
176 int ascent() const { return dim_.asc; }
178 int descent() const { return dim_.des; }
180 // Return the number of separators in the row
181 int countSeparators() const;
182 // Set the extra spacing for every separator in STRING elements
183 void setSeparatorExtraWidth(double w);
186 void add(pos_type pos, Inset const * ins, Dimension const & dim,
187 Font const & f, Change const & ch);
189 void add(pos_type pos, char_type const c,
190 Font const & f, Change const & ch);
192 void addVirtual(pos_type pos, docstring const & s,
193 Font const & f, Change const & ch);
195 void addSeparator(pos_type pos, char_type const c,
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
236 void shortenIfNeeded(pos_type const body_pos, int const width);
239 * If last element of the row is a string, compute its width
245 * Find sequences of right-to-left elements and reverse them.
246 * This should be called once the row is completely built.
248 void reverseRTL(bool rtl_par);
250 friend std::ostream & operator<<(std::ostream & os, Row const & row);
252 /// width of a separator (i.e. space)
254 /// width of hfills in the label
256 /// the left margin position of the row
258 /// the right margin of the row
261 mutable pos_type sel_beg;
263 mutable pos_type sel_end;
265 mutable bool begin_margin_sel;
267 mutable bool end_margin_sel;
270 /// Decides whether the margin is selected.
272 * \param margin_begin
276 bool isMarginSelected(bool left_margin, DocIterator const & beg,
277 DocIterator const & end) const;
280 * Returns true if a char or string with font \c f and change
281 * type \c ch can be added to the current last element of the
284 bool sameString(Font const & f, Change const & ch) const;
289 /// has the Row appearance changed since last drawing?
290 mutable bool changed_;
291 /// CRC of row contents.
292 mutable size_type crc_;
293 /// first pos covered by this row
295 /// one behind last pos covered by this row
297 // Is there is a boundary at the end of the row (display inset...)
298 bool right_boundary_;