GUI::Font Class Reference

A variable- or fixed-width fixed-size Font. More...

#include <gui_tk.h>

Inheritance diagram for GUI::Font:

List of all members.

Classes
struct	ltstr
	Compare two strings for 'less-than'. More...
Public Types
enum	SpecialChar {   CR = '\r', LF = '\n', BS = '\b', Tab = '\t',   Space = ' ', ESC = 27 }
	Characters with special appearance or meaning.
Public Member Functions
virtual int	getHeight () const =0
	Retrieve total height of font in pixels.
virtual int	getAscent () const =0
	Retrieve the ascent, i.e. the number of pixels above the base line.
template<typename STR >
int	getWidth (const STR s, Size start=0, Size len=(Size)-1) const
	Return width of a string.
virtual int	getWidth (Char c= 'M') const =0
	Retrieve width of a character.
virtual int	getWidth (const String &s, Size start=0, Size len=(Size)-1) const
	Retrieve width of a string of characters.
virtual SpecialChar	toSpecial (Char c) const
	Convert a character to an equivalent SpecialChar. May return values not in SpecialChar.
virtual Char	fromSpecial (SpecialChar c) const
	Convert a SpecialChar to an equivalent character.
Static Public Member Functions
static const Font *	getFont (const char *name)
	Return a font with the given name (case-sensitive).
static void	registry_freeall ()
static void	addFont (const char *name, Font *font)
	Add a font with a given name.
Protected Member Functions
	Font ()
	Default constructor.
virtual void	drawChar (Drawable *d, const Char c) const =0
	Draw character to a drawable at the current position.
virtual void	drawString (Drawable *d, const String &s, Size start, Size len) const
	Draw len characters to a drawable at the current position, starting at string position start.
Static Protected Attributes
static std::map< const char *, Font *, ltstr >	registry
	Font registry. Contains all known font objects indexed by name.
Friends
void	Drawable::drawText (const Char c, bool interpret)
void	Drawable::drawText (const String &s, bool interpret, Size start, Size len)

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Detailed Description

A variable- or fixed-width fixed-size Font.

These Fonts can't be scaled once instantiated, but it is possible to subclass this abstract font class to encapsulate scalable fonts. Fonts can be anti-aliasing and multi-coloured, depending on subclass. There is no encoding enforced. The font object implicitly knows about it's encoding. Because of that, there is a utility function for string examination as well.

You can't instantiate objects of this class directly, use one of the subclasses like BitmapFont.

This class provides a font registry which allows you to register and retrieve font objects using a name of your choice. It is recommended to use a naming scheme like "FontName-variant-pixelsize-encoding" where variant is "normal", "bold", "italic" or "bolditalic". No one enforces this, however.

The GUI uses some special font names. You must add them before creating the relevant GUI item.

• default - used if a requested font was not found
• title - GUI::ToplevelWindow title
• input - GUI::Input

Definition at line 1288 of file gui_tk.h.

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Member Function Documentation

static void GUI::Font::addFont	(	const char *	name,
		Font *	font
	)		[inline, static]

Add a font with a given name.

Don't delete this font once added. This class will do that for you. If a font with that name already exists, it will be replaced.

Definition at line 1338 of file gui_tk.h.

References registry.

virtual void GUI::Font::drawChar	(	Drawable *	d,
		const Char	c
	)		const [protected, pure virtual]

Draw character to a drawable at the current position.

d's current position is advanced to the position of the next character. The y coordinate is located at the baseline before and after the call.

Implemented in GUI::BitmapFont.

Referenced by drawString(), and GUI::Drawable::drawText().

virtual void GUI::Font::drawString	(	Drawable *	d,
		const String &	s,
		Size	start,
		Size	len
	)		const [inline, protected, virtual]

Draw len characters to a drawable at the current position, starting at string position start.

This can be used to provide kerning.

Definition at line 1310 of file gui_tk.h.

References drawChar().

Referenced by GUI::Drawable::drawText().

static const Font* GUI::Font::getFont

(

const char *

name

)

[inline, static]

Return a font with the given name (case-sensitive).

If no font was registered with that name, returns NULL.

Definition at line 1319 of file gui_tk.h.

References registry.

Referenced by GUI::Menubar::addMenu(), GUI::Input::checkOffset(), GUI::Input::findPos(), GUI::Input::keyDown(), GUI::Input::paint(), GUI::ToplevelWindow::paint(), GUI::Menu::paint(), GUI::Menubar::paint(), GUI::Frame::paint(), and GUI::Menu::selectItem().

virtual int GUI::Font::getWidth	(	const String &	s,
		Size	start = 0,
		Size	len = (Size)-1
	)		const [inline, virtual]

Retrieve width of a string of characters.

Can be used to provide kerning.

Definition at line 1362 of file gui_tk.h.

References getWidth().

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The documentation for this class was generated from the following files:

• src/libs/gui_tk/gui_tk.h
• src/libs/gui_tk/gui_tk.cpp