GlsFontBase Class Reference

#include <gls_font_base.h>

Classes
struct	FontAttributes
struct	GlyphAttribute
struct	InitParameters
struct	RenderAttributes

Public Types
typedef GlsUInt32	CharCode

Public Member Functions
void	BindFontTexture (GlsStateManager &gl) const
void	RenderString (GlsStateManager &gl, const GlsChar *const str, const GlsUInt32 numChars, const RenderAttributes &renderAttributes) const
const FontAttributes &	GetFontAttributes (void) const
const GlyphAttribute &	GetGlyphAttribute (const GlsChar c, const GlsBool uppercase) const

Static Public Attributes
static const GlsChar	TAB_CHAR

Protected Member Functions
	GlsFontBase (const InitParameters &initParameters)
void	DrawMappedQuad (const GlsVector2D &p1, const GlsVector2D &p2, const GlsVector2D &t1, const GlsVector2D &t2) const
virtual	~GlsFontBase ()

Protected Attributes
const FontAttributes	_fontAttributes
const GlsUInt32	_numGlyphAttributes
GlyphAttribute *const	_glyphAttributes
const GlsImage *const	_fontImage

Detailed Description

This class serves as the base class for all fonts

Invariant

_fontAttributes.IsValid(), _numGlyphAttributes > 0, _glyphAttributes != GLS_NULL and array contains valid elements, _fontImage invariant holds

Member Typedef Documentation

typedef GlsUInt32 GlsFontBase::CharCode

code associated with a character in the font

Constructor & Destructor Documentation

GlsFontBase::GlsFontBase ( const InitParameters &  initParameters )

protected

Constructor - called by derived font classes

Parameters

initParameters

initialization parameters

Precondition

initParameters.IsValid(), a GlsStateManager instance does not yet exist

Postcondition

object is constructed

virtual GlsFontBase::~GlsFontBase ( )

protectedvirtual

Destructor - shall never be called

Precondition

none

Postcondition

none

Member Function Documentation

void GlsFontBase::BindFontTexture

(

GlsStateManager &

gl

)

const

Initializes the font to begin rendering characters. This will bind the font's texture. This must be called once before invoking RenderString to draw characters.

Parameters

gl	state manager for OpenGL

Precondition

none

Postcondition

2D texturing is enabled in GL and the font texture is bound to OpenGL with the GL_MODULATE texture env mode

void GlsFontBase::DrawMappedQuad ( const GlsVector2D &  p1, const GlsVector2D &  p2, const GlsVector2D &  t1, const GlsVector2D &  t2  ) const

protected

Issue the GL vertex and texture coordinates for the quad described by the given points and texture coordinates

Parameters

p1	first corner of quad
p2	opposite corner of quad
t1	texture coord for first corner
t2	texture coord for opposite corner

Precondition

p1.IsValid(), p2.IsValid(), t1.IsValid(), t2.IsValid()

Postcondition

GL vertex and texture coordinates for the quad are issued to GL

const FontAttributes& GlsFontBase::GetFontAttributes

(

void

)

const

Get the font attributes for this font

Returns

font attributes for this font

Precondition

none

Postcondition

none

const GlyphAttribute& GlsFontBase::GetGlyphAttribute	(	const GlsChar	c,
		const GlsBool	uppercase
	)		const

Get the glyph attributes for a given char

Parameters

c	char in question
uppercase	GLS_TRUE to use uppercase version of char else GLS_FALSE

Returns

glyph attributes for c else glyph attributes for first character in font if c is not in range for this font

Precondition

none

Postcondition

none

void GlsFontBase::RenderString	(	GlsStateManager &	gl,
		const GlsChar *const	str,
		const GlsUInt32	numChars,
		const RenderAttributes &	renderAttributes
	)		const

Renders the specified character string with the given render attributes.

Parameters

gl	State Manager for OpenGL where character will be drawn
str	string to render ( must contain at least numChars characters )
numChars	number of characters in str to render (>0)
renderAttributes	desired render attributes for character

Precondition

str != GLS_NULL, numChars > 0, renderAttributues.IsValid(), font texture is bound to GL using BindFontTexture() and setup with the desired texture filter modes

Postcondition

string is drawn to OpenGL

Member Data Documentation

const FontAttributes GlsFontBase::_fontAttributes

protected

font attributes

const GlsImage* const GlsFontBase::_fontImage

protected

font texture

GlyphAttribute* const GlsFontBase::_glyphAttributes

protected

array of glyph attributes

const GlsUInt32 GlsFontBase::_numGlyphAttributes

protected

number of glyph attribues in glyphAttributes array

const GlsChar GlsFontBase::TAB_CHAR

static

tab character constant