Simple image handling class. More...

#include <Luminous/Image.hpp>

Public Member Functions
void	allocate (int width, int height, const PixelFormat &pf)
	Allocates memory, for an image of given size and format. More...

float	aspect () const
	Get the aspect ratio (width / height) of the image. More...

unsigned char *	bytes ()
	Get a pointer to image data. More...

const unsigned char *	bytes () const
	Get a pointer to image data. More...

void	changed ()
	Increments the generation count. More...

void	clear ()
	Clears the image, freeing the data.

const Luminous::Texture &	constTexture () const
	Get a texture object based on the image This function is thread-safe so it can be used in render functions. More...

bool	copyResample (const Image &source, int w, int h)
	Resample a source image using straightforward bilinear interpolation. More...

unsigned char *	data ()
	Get a pointer to image data. More...

const unsigned char *	data () const
	Get a pointer to image data. More...

void	flipVertical ()
	Flip the image upside down.

void	forgetLastLine ()
	Removes the last line from the image. More...

void	forgetLastLines (int n)
	Remove lines from the bottom of the image. More...

bool	forgetLastPixels (int n)
	Remove pixels from the right edge of the image. More...

void	fromData (const unsigned char *bytes, int width, int height, PixelFormat format)
	Create an image object from data provided by the user. More...

size_t	generation () const
	The generation count of the image object The generation count can be used to indicate that the image has changed, and one should update the corresponding OpenGL texture wo match the same generation. More...

bool	hasAlpha () const
	Returns true if the image has an alpha channel. More...

bool	hasTexture () const
	Check if the image associated texture has been initialized. More...

int	height () const
	Get the image height. More...

	Image ()
	Construct an empty image.

	Image (const Image &img)
	Copy constructor. More...

	Image (Image &&img)
	Move constructor. More...

bool	isEmpty () const
	Returns true if the image does not contain any data. More...

unsigned char *	line (unsigned y)
	Get a pointer to image data on specific line. More...

const unsigned char *	line (unsigned y) const
	Get a pointer to image data on specific line. More...

int	lineSize () const
	The number of bytes a single line in the image takes. More...

void	makeValidTexture ()
	Checks that the image dimensions are feasible for a texture. More...

void	minify (const Image &src, int w, int h)
	Scale an image to a smaller size. More...

Image &	operator= (const Image &img)
	Makes a deep copy of the given image. More...

Image &	operator= (Image &&img)
	Move operator. More...

Nimble::Vector4	pixel (int x, int y) const
	Gets the color of a given pixel. More...

unsigned char	pixelAlpha (Nimble::Vector2 relativeCoord) const
	Returns the alpha value [0,255] for the given relative coordinates in the image. More...

const PixelFormat &	pixelFormat () const
	Returns the pixel format of the image.

bool	quarterSize (const Image &source)
	Down-sample the given image to quarter size. More...

bool	read (const QString &filename)
	Load an image from the given filename. More...

Nimble::Vector4	safePixel (int x, int y) const
	Get a pixel from the image. More...

void	setPixel (unsigned x, unsigned y, const Nimble::Vector4 &pixel)
	Set a pixel to given color. More...

bool	setPixelFormat (const PixelFormat &format)
	Sets the new format and converts the image data to new format if necessary. More...

Nimble::Size	size () const
	Get the image size. More...

Luminous::Texture &	texture () const
	Get a texture object based on the image This function is thread-safe so it can be used in render functions. More...

int	width () const
	Get the image width. More...

bool	write (const QString &filename) const
	Save the image to a file. More...

void	zero ()
	Fills the image with zeros.

virtual	~Image ()
	Destructor.

Static Public Member Functions
static CodecRegistry *	codecs ()
	Returns a pointer to the file-format codecs. More...

static bool	ping (const QString &filename, ImageInfo &info)
	Get basic image information from a file. More...

Protected Attributes
unsigned char *	m_data
	Pointer to the raw image data. More...

size_t	m_generation
	Generation count of the image used to indicate changes in the image data to determine when associated textures should be updated. More...

int	m_height
	Height of the image in pixels.

PixelFormat	m_pixelFormat
	Pixel format of the image data.

int	m_width
	Width of the image in pixels.

Detailed Description

Simple image handling class.

This class is used mainly to load/save image data in various formats. It provides minimal image processing support (resizing).

The image data is stored in a single, straightforward buffer.

Examples:: Widget3DExample.cpp.

Constructor & Destructor Documentation

Luminous::Image::Image ( const Image & img )

Copy constructor.

Parameters

img	image to copy

Luminous::Image::Image ( Image && img )

Move constructor.

Parameters

img	image to move

Member Function Documentation

void Luminous::Image::allocate	(	int	width,
		int	height,
		const PixelFormat &	pf
	)

Allocates memory, for an image of given size and format.

Parameters

width	width in pixels
height	height in pixels
pf	pixel format

float Luminous::Image::aspect ( ) const

inline

Get the aspect ratio (width / height) of the image.

Returns: aspect ratio

unsigned char* Luminous::Image::bytes ( )

inline

Get a pointer to image data.

Returns: pointer to image data

const unsigned char* Luminous::Image::bytes ( ) const

inline

Get a pointer to image data.

Returns: pointer to image data

void Luminous::Image::changed ( )

inline

Increments the generation count.

This function should be called when the image has been modified.

static CodecRegistry* Luminous::Image::codecs ( )

static

Returns a pointer to the file-format codecs.

Returns: pointer to the codec registry

const Luminous::Texture& Luminous::Image::constTexture ( ) const

Get a texture object based on the image This function is thread-safe so it can be used in render functions.

Returns: texture matching the image

bool Luminous::Image::copyResample	(	const Image &	source,
		int	w,
		int	h
	)

Resample a source image using straightforward bilinear

interpolation.

Parameters

source	image to resample
w	new width
h	new height

Returns: true if the resamping succeed

unsigned char* Luminous::Image::data ( )

inline

Get a pointer to image data.

Returns: pointer to image data

const unsigned char* Luminous::Image::data ( ) const

inline

Get a pointer to image data.

Returns: pointer to image data

void Luminous::Image::forgetLastLine ( )

Removes the last line from the image.

void Luminous::Image::forgetLastLines ( int n )

Remove lines from the bottom of the image.

Parameters

n	number of lines to remove

bool Luminous::Image::forgetLastPixels ( int n )

Remove pixels from the right edge of the image.

Works for RGB images.

Parameters

n	number of pixels to remove

Returns: false if the image is of unsupported pixel format

void Luminous::Image::fromData	(	const unsigned char *	bytes,
		int	width,
		int	height,
		PixelFormat	format
	)

Create an image object from data provided by the user.

Parameters

bytes	pointer to image data
width	width of the image data
height	height of the image data
format	pixel format of the image data

size_t Luminous::Image::generation ( ) const

inline

The generation count of the image object The generation count can be used to indicate that the image has changed, and one should update the corresponding OpenGL texture wo match the same generation.

Returns: current generation count

bool Luminous::Image::hasAlpha ( ) const

Returns true if the image has an alpha channel.

Returns: true if the image has alpha channel

bool Luminous::Image::hasTexture ( ) const

Check if the image associated texture has been initialized.

The texture is initialized lazily when calling texture() method.

Returns: true if the texture has been created

See Also: texture

int Luminous::Image::height ( ) const

inline

Get the image height.

Returns: height in pixels

bool Luminous::Image::isEmpty ( ) const

inline

Returns true if the image does not contain any data.

Returns: true if the data is nullptr; otherwise false

unsigned char* Luminous::Image::line ( unsigned y )

inline

Get a pointer to image data on specific line.

Parameters

y	line to query for

Returns: pointer to beginning of the line

const unsigned char* Luminous::Image::line ( unsigned y ) const

inline

Get a pointer to image data on specific line.

Parameters

y	line to query for

Returns: pointer to beginning of the line

int Luminous::Image::lineSize ( ) const

inline

The number of bytes a single line in the image takes.

Returns: line size in bytes

void Luminous::Image::makeValidTexture ( )

Checks that the image dimensions are feasible for a texture.

In practice this functions removes pixels from the right and bottom, to make the width and height multiples of two.

void Luminous::Image::minify	(	const Image &	src,
		int	w,
		int	h
	)

Scale an image to a smaller size.

The given width and height should be smaller than in the source image.

Parameters

src	source image
w	new width
h	new height

Image& Luminous::Image::operator= ( const Image & img )

Makes a deep copy of the given image.

Parameters

img	image to copy

Returns: reference to this image

Image& Luminous::Image::operator= ( Image && img )

Move operator.

Parameters

img	image to move

Returns: reference to this image

static bool Luminous::Image::ping	(	const QString &	filename,
		ImageInfo &	info
	)

static

Get basic image information from a file.

This function does not decode the actual image data, typically just the header.

Parameters

	filename	filename to query
[out]	info	image information

Returns: true if the operation was successful; otherwise false

Nimble::Vector4 Luminous::Image::pixel	(	int	x,
		int	y
	)		const

Gets the color of a given pixel.

The color is normalized, with each component in range 0-1.

Parameters

x	pixel x coordinate
y	pixel y coordinate

Returns: color at the given pixel

unsigned char Luminous::Image::pixelAlpha ( Nimble::Vector2 relativeCoord ) const

Returns the alpha value [0,255] for the given relative coordinates in the image.

Parameters

relativeCoord relative pixel coordinate x,y in [0,1]

Returns: alpha of the given pixel or 255 if image does not have alpha channel

bool Luminous::Image::quarterSize ( const Image & source )

Down-sample the given image to quarter size.

Parameters

source image to resample

Returns: true if resampling succeeded

bool Luminous::Image::read ( const QString & filename )

Load an image from the given filename.

Parameters

filename name of the file to read from

Returns: true if the image was successfully read

Nimble::Vector4 Luminous::Image::safePixel	(	int	x,
		int	y
	)		const

Get a pixel from the image.

This function does additional checks for make sure the requested pixels are within the image. If the requested pixel falls outside the image, transparent color is returned. The color is normalized.

Parameters

x	pixel x coordinate
y	pixel y coordinate

Returns: pixel color

void Luminous::Image::setPixel	(	unsigned	x,
		unsigned	y,
		const Nimble::Vector4 &	pixel
	)

Set a pixel to given color.

The color must be normalized.

Parameters

x	x coordinate of the pixel
y	y coordinate of the pixel
pixel	pixel color

bool Luminous::Image::setPixelFormat ( const PixelFormat & format )

Sets the new format and converts the image data to new format if necessary.

Parameters

format new pixel format for the image

Returns: Returns true if the conversion was successful

Nimble::Size Luminous::Image::size ( ) const

inline

Get the image size.

Returns: image size in pixels

Luminous::Texture& Luminous::Image::texture ( ) const

Get a texture object based on the image This function is thread-safe so it can be used in render functions.

Returns: texture matching the image

int Luminous::Image::width ( ) const

inline

Get the image width.

Returns: width in pixels

bool Luminous::Image::write ( const QString & filename ) const

Save the image to a file.

Parameters

filename name of the file to write to

Returns: true if the image was successfully written

Member Data Documentation

unsigned char* Luminous::Image::m_data

protected

Pointer to the raw image data.

size_t Luminous::Image::m_generation

protected

Generation count of the image used to indicate changes in the image data to determine when associated textures should be updated.

Public Member Functions

Static Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation