#ifndef FONT_METRICS_H
#define FONT_METRICS_H
-#include "support/docstring.h"
+#include "support/strfwd.h"
/**
* A class holding helper functions for determining
* <- width ->
* --------------+----------+-------<maxDescent
*
+ * Caution: All char_type and docstring arguments of any method of this class
+ * are no UCS4 chars or strings if the font is a symbol font. They simply
+ * denote the code points of the font instead. You have to keep this in mind
+ * when you implement the methods in a frontend. You must not pass these
+ * parameters to a unicode conversion function in particular.
*/
namespace lyx {
+
+class Dimension;
+
namespace frontend {
class FontMetrics
virtual int maxAscent() const = 0;
/// return the maximum descent of the font
virtual int maxDescent() const = 0;
+ /// return default dimension of the font.
+ /// \warning \c width is set to zero.
+ virtual Dimension const defaultDimension() const = 0;
+ /// return the em size
+ virtual int em() const = 0;
+ /// return the x height
+ virtual int xHeight() const = 0;
+ /// return the width of a line for underlining
+ virtual int lineWidth() const = 0;
+ /// return the distance from the base line to where an underline
+ /// should be drawn.
+ virtual int underlinePos() const = 0;
+ /// return the distance from the base line to where the strike out line
+ /// should be drawn.
+ virtual int strikeoutPos() const = 0;
+
+ /// return the width of the char in the font
+ virtual int width(char_type c) const = 0;
/// return the ascent of the char in the font
- virtual int ascent(lyx::char_type c) const = 0;
+ virtual int ascent(char_type c) const = 0;
/// return the descent of the char in the font
- virtual int descent(lyx::char_type c) const = 0;
+ virtual int descent(char_type c) const = 0;
/// return the left bearing of the char in the font
- virtual int lbearing(lyx::char_type c) const = 0;
+ virtual int lbearing(char_type c) const = 0;
/// return the right bearing of the char in the font
- virtual int rbearing(lyx::char_type c) const = 0;
+ virtual int rbearing(char_type c) const = 0;
/// return the width of the string in the font
- virtual int width(lyx::char_type const * s, size_t n) const = 0;
+ virtual int width(docstring const & s) const = 0;
/// FIXME ??
- virtual int signedWidth(lyx::docstring const & s) const = 0;
+ virtual int signedWidth(docstring const & s) const = 0;
+ /**
+ * return the x offset of a position in the string. The
+ * direction of the string is forced, and the returned value
+ * is from the left edge of the word, not from the start of the string.
+ * \param rtl is true for right-to-left layout
+ * \param ws is the amount of extra inter-word space applied text justication.
+ */
+ virtual int pos2x(docstring const & s, int pos, bool rtl, double ws) const = 0;
+ /**
+ * return the position in the string for a given x offset. The
+ * direction of the string is forced, and the returned value
+ * is from the left edge of the word, not from the start of the string.
+ * the offset x is updated to match the closest position in the string.
+ * \param rtl is true for right-to-left layout
+ * \param ws is the amount of extra inter-word space applied text justication.
+ */
+ virtual int x2pos(docstring const & s, int & x, bool rtl, double ws) const = 0;
+ /**
+ * Break string at width at most x.
+ * \return true if successful
+ * \param rtl is true for right-to-left layout
+ * \param force is false for breaking at word separator, true for
+ * arbitrary position.
+ */
+ virtual bool breakAt(docstring & s, int & x, bool rtl, bool force) const = 0;
+ /// return char dimension for the font.
+ virtual Dimension const dimension(char_type c) const = 0;
/**
* fill in width,ascent,descent with the values for the
* given string in the font.
*/
- virtual void rectText(lyx::docstring const & str,
+ virtual void rectText(docstring const & str,
int & width,
int & ascent,
int & descent) const = 0;
/**
* fill in width,ascent,descent with the values for the
- * given string in the font for a button.
+ * given string in the font for a button with given offset.
*/
- virtual void buttonText(lyx::docstring const & str,
+ virtual void buttonText(docstring const & str,
+ const int offset,
int & width,
int & ascent,
int & descent) const = 0;
/// return the maximum descent of the font
- inline int maxHeight() const {
- return maxAscent() + maxDescent();
- }
+ inline int maxHeight() const { return maxAscent() + maxDescent(); }
/// return the descent of the char in the font
- inline int height(lyx::char_type c) const
- {
- return ascent(c) + descent(c);
- }
+ inline int height(char_type c) const { return ascent(c) + descent(c); }
/// return the inner width of the char in the font
- inline int center(lyx::char_type c) const {
+ inline int center(char_type c) const {
return (rbearing(c) - lbearing(c)) / 2;
}
- /// return the width of the char in the font
- inline int width(lyx::char_type c) const
- {
- lyx::char_type tmp[2] = { c, L'\0'};
- return width(tmp, 1);
- }
-
- /// return the width of the string in the font
- inline int width(lyx::docstring const & s) const
- {
- return s.empty() ? 0 : width(s.data(), s.length());
- }
+ /// return the number of expanding characters taken into account for
+ /// increased inter-word spacing during justification
+ virtual int countExpanders(docstring const & str) const = 0;
};
+
} // namespace frontend
-} // namespace lyx
-class LyXFont;
+class Font;
+class FontInfo;
-extern lyx::frontend::FontMetrics const & theFontMetrics(LyXFont const & f);
+/// Implementation is in Application.cpp
+frontend::FontMetrics const & theFontMetrics(Font const & f);
+frontend::FontMetrics const & theFontMetrics(FontInfo const & fi);
+
+} // namespace lyx
#endif // FONT_METRICS_H