Fixed-size bitmap font backed by a caller-supplied glyph table. More...

#include <BitmapFont.h>

Inheritance diagram for BitmapFont< Width, Height, RowT, RGB_T >:

[legend]

Collaboration diagram for BitmapFont< Width, Height, RowT, RGB_T >:

Public Types
using	Glyph = std::array< RowT, Height >
	Glyph storage: one row entry per pixel row.

using	CodePoint = uint32_t
	Unicode code point type used during UTF-8 decoding.

Public Member Functions
	BitmapFont (const Glyph *table, size_t glyphCount, char firstChar=' ')
	Creates a fixed bitmap font over a contiguous glyph table.

void	setProportional (bool proportional) override

bool	isProportional () const override
	Returns whether proportional spacing is enabled.

uint8_t	glyphLeftOffset (CodePoint codePoint) const

uint8_t	glyphEffectiveWidth (CodePoint codePoint) const

uint8_t	glyphAdvanceWidth (CodePoint codePoint) const

const Glyph &	glyph (char character) const
	Returns the glyph for an 8-bit character.

virtual const Glyph &	glyph (CodePoint codePoint) const

bool	pixel (CodePoint codePoint, uint8_t x, uint8_t y) const
	Returns whether a pixel is set in a code point glyph.

void	drawCodePoint (ISurface< RGB_T > &target, int16_t x, int16_t y, CodePoint codePoint, RGB_T foreground, RGB_T background=RGB_T(0), bool opaque=false, uint8_t scale=1) const

void	drawChar (ISurface< RGB_T > &target, int16_t x, int16_t y, char character, RGB_T foreground, RGB_T background=RGB_T(0), bool opaque=false, uint8_t scale=1) const
	Draws a single character.

void	drawText (ISurface< RGB_T > &target, int16_t x, int16_t y, const char *text, RGB_T foreground, RGB_T background=RGB_T(0), bool opaque=false, uint8_t scale=1, uint8_t spacing=1, uint8_t lineSpacing=1) const override
	Draws a UTF-8 text string.

size_t	measureTextWidth (const char *text, uint8_t scale=1, uint8_t spacing=1) const override
	Returns the width of the longest text line in pixels.

size_t	measureTextHeight (const char *text, uint8_t scale=1, uint8_t lineSpacing=1) const override
	Returns the total text height in pixels.

size_t	getHeight (uint8_t scale) const override
	Returns the scaled glyph height in pixels.

Public Member Functions inherited from IFont< RGB_T >
virtual	~IFont ()=default
	Destroys the font interface.

virtual void	drawText (ISurface< RGB_T > &target, int16_t x, int16_t y, const char *text, RGB_T foreground, RGB_T background, bool opaque=false, uint8_t scale=1, uint8_t spacing=1, uint8_t lineSpacing=1) const =0
	Draws a text string onto a framebuffer target.

virtual size_t	measureTextWidth (const char *text, uint8_t scale=1, uint8_t spacing=1) const =0
	Returns the width of the longest text line in pixels.

virtual size_t	measureTextHeight (const char *text, uint8_t scale=1, uint8_t lineSpacing=1) const =0
	Returns the total text height in pixels.

virtual size_t	getHeight (uint8_t scale) const =0
	Returns the scaled glyph height in pixels.

virtual void	setProportional (bool proportional)

virtual bool	isProportional () const
	Returns whether proportional spacing is enabled.

Static Public Attributes
static constexpr uint8_t	kGlyphWidth = Width
	Width of a glyph in pixels.

static constexpr uint8_t	kGlyphHeight = Height
	Height of a glyph in pixels.

static constexpr uint8_t	kBlankGlyphWidth = (kGlyphWidth > 2) ? kGlyphWidth - 2 : kGlyphWidth

Detailed Description

template<uint8_t Width, uint8_t Height, typename RowT, typename RGB_T = RGB565>
class tinygpu::BitmapFont< Width, Height, RowT, RGB_T >

Fixed-size bitmap font backed by a caller-supplied glyph table.

Template Parameters

Width	Glyph width in pixels.
Height	Glyph height in pixels.
RowT	Unsigned integer type used to store one glyph row. Only the `Width` most significant bits of each row are used (bit `Width-1` is the left-most pixel), mirroring the bit order used by Font5x7.
RGB_T	The pixel color type. Can be RGB565, RGB666, RGB888, etc.

Concrete fonts (e.g. converted from vendor font tables) subclass this and pass their own glyph table to the constructor. Only a contiguous ASCII range starting at firstChar is supported; any code point outside that range falls back to the glyph for '?'.

Member Typedef Documentation

◆ CodePoint

using CodePoint = uint32_t

Unicode code point type used during UTF-8 decoding.

◆ Glyph

using Glyph = std::array<RowT, Height>

Glyph storage: one row entry per pixel row.

Constructor & Destructor Documentation

◆ BitmapFont()

BitmapFont	(	const Glyph *	table,
		size_t	glyphCount,
		char	firstChar = `' '`
	)

inline

Creates a fixed bitmap font over a contiguous glyph table.

Member Function Documentation

◆ drawChar()

void drawChar	(	ISurface< RGB_T > &	target,
		int16_t	x,
		int16_t	y,
		char	character,
		RGB_T	foreground,
		RGB_T	background = `RGB_T(0)`,
		bool	opaque = `false`,
		uint8_t	scale = `1`
	)		const

inline

Draws a single character.

◆ drawCodePoint()

void drawCodePoint	(	ISurface< RGB_T > &	target,
		int16_t	x,
		int16_t	y,
		CodePoint	codePoint,
		RGB_T	foreground,
		RGB_T	background = `RGB_T(0)`,
		bool	opaque = `false`,
		uint8_t	scale = `1`
	)		const

inline

Draws a single Unicode code point. In proportional mode, leading blank columns of the glyph are skipped so the visible pixels start at x.

◆ drawText()

void drawText	(	ISurface< RGB_T > &	target,
		int16_t	x,
		int16_t	y,
		const char *	text,
		RGB_T	foreground,
		RGB_T	background = `RGB_T(0)`,
		bool	opaque = `false`,
		uint8_t	scale = `1`,
		uint8_t	spacing = `1`,
		uint8_t	lineSpacing = `1`
	)		const

inlineoverridevirtual

Draws a UTF-8 text string.

Implements IFont< RGB_T >.

◆ getHeight()

size_t getHeight ( uint8_t scale ) const

inlineoverridevirtual

Returns the scaled glyph height in pixels.

Implements IFont< RGB_T >.

◆ glyph() [1/2]

const Glyph & glyph ( char character ) const

inline

Returns the glyph for an 8-bit character.

◆ glyph() [2/2]

virtual const Glyph & glyph ( CodePoint codePoint ) const

inlinevirtual

Returns the glyph for a Unicode code point. Virtual so a subclass with its own extra fallback logic (e.g. Font5x7's mapping of Latin-1/CP1252-ish codepoints outside its stored ASCII range) can override just this lookup and get every other method here - pixel(), drawText(), measureTextWidth(), ... - for free, since they all call glyph() internally rather than duplicating the lookup themselves.

Reimplemented in Font5x7< RGB_T >, Font5x7< RGB565 >, Font5x7< tinygpu::RGB565 >, Font5x7< RGB_T >, Font5x7< RGB565 >, and Font5x7< tinygpu::RGB565 >.

◆ glyphAdvanceWidth()

uint8_t glyphAdvanceWidth ( CodePoint codePoint ) const

inline

Returns the advance width (in unscaled pixels) used to move the cursor past a code point's glyph, honoring proportional mode when enabled.

◆ glyphEffectiveWidth()

uint8_t glyphEffectiveWidth ( CodePoint codePoint ) const

inline

Returns the effective (used) width in pixels of a code point's glyph, i.e. the span from its left-most to right-most set pixel column, inclusive. Glyphs with no set pixels (e.g. the space) fall back to a default blank width.

◆ glyphLeftOffset()

uint8_t glyphLeftOffset ( CodePoint codePoint ) const

inline

Returns the left-most column (0-based) that has a set pixel in a code point's glyph. Glyphs with no set pixels (e.g. the space) return 0.

◆ isProportional()

bool isProportional ( ) const

inlineoverridevirtual

Returns whether proportional spacing is enabled.

Reimplemented from IFont< RGB_T >.

◆ measureTextHeight()

size_t measureTextHeight	(	const char *	text,
		uint8_t	scale = `1`,
		uint8_t	lineSpacing = `1`
	)		const

inlineoverridevirtual

Returns the total text height in pixels.

Implements IFont< RGB_T >.

◆ measureTextWidth()

size_t measureTextWidth	(	const char *	text,
		uint8_t	scale = `1`,
		uint8_t	spacing = `1`
	)		const

inlineoverridevirtual

Returns the width of the longest text line in pixels.

Implements IFont< RGB_T >.

◆ pixel()

bool pixel	(	CodePoint	codePoint,
		uint8_t	x,
		uint8_t	y
	)		const

inline

Returns whether a pixel is set in a code point glyph.

◆ setProportional()

void setProportional ( bool proportional )

inlineoverridevirtual

Enables/disables proportional spacing based on each glyph's effective (used) width instead of the fixed glyph width.

Reimplemented from IFont< RGB_T >.

Member Data Documentation

◆ kBlankGlyphWidth

constexpr uint8_t kBlankGlyphWidth = (kGlyphWidth > 2) ? kGlyphWidth - 2 : kGlyphWidth

staticconstexpr

Advance width used in proportional mode for glyphs with no set pixels (e.g. the space character).

◆ kGlyphHeight

constexpr uint8_t kGlyphHeight = Height

staticconstexpr

Height of a glyph in pixels.

◆ kGlyphWidth

constexpr uint8_t kGlyphWidth = Width

staticconstexpr

Width of a glyph in pixels.

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

src/TinyGPU/Font/BitmapFont.h

Public Types

Public Member Functions

Static Public Attributes

Detailed Description

Member Typedef Documentation

◆ CodePoint

◆ Glyph

Constructor & Destructor Documentation

◆ BitmapFont()

Member Function Documentation

◆ drawChar()

◆ drawCodePoint()

◆ drawText()

◆ getHeight()

◆ glyph() [1/2]

◆ glyph() [2/2]

◆ glyphAdvanceWidth()

◆ glyphEffectiveWidth()

◆ glyphLeftOffset()

◆ isProportional()

◆ measureTextHeight()

◆ measureTextWidth()

◆ pixel()

◆ setProportional()

Member Data Documentation

◆ kBlankGlyphWidth

◆ kGlyphHeight

◆ kGlyphWidth