TurtleBrains::Graphics::Text Class Reference

#include <tb_text.h>

Inheritance diagram for TurtleBrains::Graphics::Text:

Public Member Functions
	Text (const tbCore::tbString &text=tb_string(""), const float pointSize=kDefaultFontSize, const tbCore::tbString &fontFilepath=kDefaultFontFile)
virtual	~Text (void)
void	SetText (const tbCore::tbString &text, const float pointSize, const tbCore::tbString &fontFilepath)
void	SetText (const tbCore::tbString &text)
PixelSpace	GetWidth (void) const
PixelSpace	GetHeight (void) const
Public Member Functions inherited from TurtleBrains::Graphics::Graphic
	Graphic (void)
	Graphic (const Graphic &other)
virtual	~Graphic (void)
bool	IsActive (void) const
void	SetActive (const bool isActive)
void	Update (const float deltaTime)
bool	IsVisible (void) const
void	SetVisible (const bool isVisible)
void	Render (void) const
const tbMath::Vector2 &	GetPosition (void) const
void	SetPosition (const float x, const float y)
void	SetPosition (const tbMath::Vector2 &position)
float	GetDepth (void) const
void	SetDepth (const float newDepth)
bool	IsRelative (void) const
virtual void	SetColor (const tbGraphics::Color &newColor)

Static Public Attributes
static const float	kDefaultFontSize
static const tbCore::tbString	kDefaultFontFile

Protected Member Functions
virtual void	OnRender (void) const override
Protected Member Functions inherited from TurtleBrains::Graphics::Graphic
virtual void	OnUpdate (const float deltaTime)
const Color &	GetColor (void) const

Detailed Description

The basic TextObject provides a minimalistic, but powerful true-type font api, each instance of the TextObject creates a GL texture that will be rendered to the screen as appropriate. It does take a little overhead to create the TextObject, so don't create a bunch of them over and over each frame.

Note

the Constructor seems to take a lot of parameters, but the primary use case in mind with the particular design is for the TextObject to be derived and changed so only the first parameter, text, is actually used.

class MySpecialTextObject : public TextObject { public: MySpecialText(const tbString& text) : TextObject(text, "Path/To/Some/Font.ttf", 20.0f) { } }

Constructor & Destructor Documentation

TurtleBrains::Graphics::Text::Text ( const tbCore::tbString &  text = tb_string(""), const float  pointSize = kDefaultFontSize, const tbCore::tbString &  fontFilepath = kDefaultFontFile  )

explicit

This constructor does all the heavy lifting for the TextObject. If the font specified by fontFilepath is not loaded, it will be loaded, and then a small GL texture will be rasterized and stored to be used by the Draw() method. There are several ways the constructor can fail, and if it does fail the tb_error_if behavior will be invoked, either throwing exceptions, asserts, or other.

Parameters

text	A string representing the actual letters/symbols to be displayed by the object.
fontFilepath	The filepath to the truetype-font to use for this text object, file must exist or an error condition will be triggered. Set as kDefaultFontFile, the font will be the default font as supplied by TurtleBrains.
pointSize	How large this TextObject should be rasterized at.

virtual TurtleBrains::Graphics::Text::~Text ( void  )

virtual

Cleans up any resources used by the Text object, with the current exception that a Font will remain loaded for other Text objects to use. This will likely change in the future to unload Fonts, except for the default font, that have no Text objects referencing.

Member Function Documentation

PixelSpace TurtleBrains::Graphics::Text::GetHeight

(

void

)

const

Returns the height of the text in PixelSpace which may include some padding around the edges.

PixelSpace TurtleBrains::Graphics::Text::GetWidth

(

void

)

const

Returns the width of the text in PixelSpace which may include some padding around the edges.

virtual void TurtleBrains::Graphics::Text::OnRender ( void  ) const

overrideprotectedvirtual

Draws the precomputed image from the constructor to the screen. The location of the TextObject is determined by the last call to SetPosition(), as is the color with SetColor().

Implements TurtleBrains::Graphics::Graphic.

void TurtleBrains::Graphics::Text::SetText	(	const tbCore::tbString &	text,
		const float	pointSize,
		const tbCore::tbString &	fontFilepath
	)

SetText is the heavy lifter of the object, it actually creates the small GL texture for of the rasterized letters/symbols from the true-type font and prepares everything to be displayed. It can be a fairly expensive call, so avoid changing the text, size or font when possible.

Parameters

text	the string of letters to display when rendered.
pointSize	is optional to change the size of the text should when rasterized. This will effect the width and height of the displayed text.
fontFilepath	is optional to change the font of the text object.

Note

Rasterizing the text is the heavy lifter of the Text object and should only be called when needed.

void TurtleBrains::Graphics::Text::SetText

(

const tbCore::tbString &

text

)

SetText is the heavy lifter of the object, it actually creates the small GL texture for of the rasterized letters/symbols from the true-type font and prepares everything to be displayed. It can be a fairly expensive call, so avoid changing the text, size or font when possible.

Parameters

text	the string of letters to display when rendered.

Note

Rasterizing the text is the heavy lifter of the Text object and should only be called when needed.

Member Data Documentation

const tbCore::tbString TurtleBrains::Graphics::Text::kDefaultFontFile

static

The default font file automatically created by TurtleBrains if a Text object is created with default.

const float TurtleBrains::Graphics::Text::kDefaultFontSize

static

the default font size for a Text object created without specifying a size.