Class representing an image file. More...

#include <OgreImage.h>

Inheritance diagram for Ogre::Image:

Public Types
enum	Filter { FILTER_NEAREST, FILTER_LINEAR, FILTER_BILINEAR, FILTER_BOX, FILTER_TRIANGLE, FILTER_BICUBIC }

Public Member Functions
	Image ()
	Standard constructor. More...

	Image (const Image &img)
	Copy-constructor - copies all the data from the target image. More...

	~Image ()
	Standard destructor. More...

Image &	combineTwoImagesAsRGBA (const Image &rgb, const Image &alpha, PixelFormat format=PF_BYTE_RGBA)
	Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha). More...

DataStreamPtr	encode (const String &formatextension)
	Encode the image and return a stream to the data. More...

Image &	flipAroundX ()
	Flips (mirrors) the image around the X-axis. More...

Image &	flipAroundY ()
	Flips (mirrors) the image around the Y-axis. More...

void	freeMemory ()
	Delete all the memory held by this image, if owned by this image (not dynamic) More...

uchar	getBPP () const
	Returns the number of bits per pixel. More...

ColourValue	getColourAt (size_t x, size_t y, size_t z) const
	Get colour value from a certain location in the image. More...

uchar *	getData (void)
	Returns a pointer to the internal image buffer. More...

const uchar *	getData () const
	Returns a const pointer to the internal image buffer. More...

uint32	getDepth (void) const
	Gets the depth of the image. More...

PixelFormat	getFormat () const
	Returns the image format. More...

bool	getHasAlpha () const
	Returns true if the image has an alpha component. More...

uint32	getHeight (void) const
	Gets the height of the image in pixels. More...

size_t	getNumFaces (void) const
	Get the number of faces of the image. More...

uint32	getNumMipmaps () const
	Returns the number of mipmaps contained in the image. More...

PixelBox	getPixelBox (size_t face=0, size_t mipmap=0) const
	Get a PixelBox encapsulating the image data of a mipmap. More...

size_t	getRowSpan (void) const
	Gets the physical width in bytes of each row of pixels. More...

size_t	getSize () const
	Returns the size of the data buffer. More...

uint32	getWidth (void) const
	Gets the width of the image in pixels. More...

bool	hasFlag (const ImageFlags imgFlag) const
	Returns true if the image has the appropriate flag set. More...

Image &	load (const String &filename, const String &groupName)
	Loads an image file. More...

Image &	load (const DataStreamPtr &stream, const String &type=BLANKSTRING)
	Loads an image file from a stream. More...

Image &	loadDynamicImage (uchar *data, uint32 width, uint32 height, uint32 depth, PixelFormat format, bool autoDelete=false, size_t numFaces=1, uint32 numMipMaps=0)
	Stores a pointer to raw data in memory. More...

Image &	loadDynamicImage (uchar *data, uint32 width, uint32 height, PixelFormat format)

Image &	loadRawData (const DataStreamPtr &stream, uint32 width, uint32 height, uint32 depth, PixelFormat format, size_t numFaces=1, uint32 numMipMaps=0)
	Loads raw data from a stream. More...

Image &	loadRawData (const DataStreamPtr &stream, uint32 width, uint32 height, PixelFormat format)

Image &	loadTwoImagesAsRGBA (const String &rgbFilename, const String &alphaFilename, const String &groupName, PixelFormat format=PF_BYTE_RGBA)
	Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha). More...

Image &	loadTwoImagesAsRGBA (const DataStreamPtr &rgbStream, const DataStreamPtr &alphaStream, PixelFormat format=PF_BYTE_RGBA, const String &rgbType=BLANKSTRING, const String &alphaType=BLANKSTRING)
	Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha). More...

Image &	operator= (const Image &img)
	Assignment operator - copies all the data from the target image. More...

void	resize (ushort width, ushort height, Filter filter=FILTER_BILINEAR)
	Resize a 2D image, applying the appropriate filter. More...

void	save (const String &filename)
	Save the image as a file. More...

void	setColourAt (ColourValue const &cv, size_t x, size_t y, size_t z)
	Set colour value at a certain location in the image. More...

Static Public Member Functions
static void	applyGamma (uchar *buffer, Real gamma, size_t size, uchar bpp)
	Does gamma adjustment. More...

static size_t	calculateSize (size_t mipmaps, size_t faces, uint32 width, uint32 height, uint32 depth, PixelFormat format)
	Static function to calculate size in bytes from the number of mipmaps, faces and the dimensions. More...

static String	getFileExtFromMagic (DataStreamPtr stream)
	Static function to get an image type string from a stream via magic numbers. More...

static void	scale (const PixelBox &src, const PixelBox &dst, Filter filter=FILTER_BILINEAR)
	Scale a 1D, 2D or 3D image volume. More...

Detailed Description

Class representing an image file.

Remarks: The Image class usually holds uncompressed image data and is the only object that can be loaded in a texture. Image objects handle image data decoding themselves by the means of locating the correct Codec object for each data type.

: Typically, you would want to use an Image object to load a texture when extra processing needs to be done on an image before it is loaded or when you want to blit to an existing texture.

Member Enumeration Documentation

◆ Filter

enum Ogre::Image::Filter

Enumerator
FILTER_NEAREST
FILTER_LINEAR
FILTER_BILINEAR
FILTER_BOX
FILTER_TRIANGLE
FILTER_BICUBIC

Constructor & Destructor Documentation

◆ Image() [1/2]

Ogre::Image::Image ( )

Standard constructor.

◆ Image() [2/2]

Ogre::Image::Image ( const Image & img )

Copy-constructor - copies all the data from the target image.

◆ ~Image()

Ogre::Image::~Image ( )

Standard destructor.

Member Function Documentation

◆ operator=()

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

Assignment operator - copies all the data from the target image.

◆ flipAroundY()

Image& Ogre::Image::flipAroundY ( )

Flips (mirrors) the image around the Y-axis.

Remarks

An example of an original and flipped image:

                
    originalimg
    00000000000
    00000000000
    00000000000
    00000000000
    00000000000
    ---------—> flip axis
    00000000000
    00000000000
    00000000000
    00000000000
    00000000000
    originalimg

◆ flipAroundX()

Image& Ogre::Image::flipAroundX ( )

Flips (mirrors) the image around the X-axis.

Remarks

An example of an original and flipped image:

            flip axis
                |
    originalimg|gmilanigiro
    00000000000|00000000000
    00000000000|00000000000
    00000000000|00000000000
    00000000000|00000000000
    00000000000|00000000000

◆ loadDynamicImage() [1/2]

Image& Ogre::Image::loadDynamicImage	(	uchar *	data,
		uint32	width,
		uint32	height,
		uint32	depth,
		PixelFormat	format,
		bool	autoDelete = `false`,
		size_t	numFaces = `1`,
		uint32	numMipMaps = `0`
	)

Stores a pointer to raw data in memory.

The pixel format has to be specified.

Remarks: This method loads an image into memory held in the object. The pixel format will be either greyscale or RGB with an optional Alpha component. The type can be determined by calling getFormat().

Note

Whilst typically your image is likely to be a simple 2D image, you can define complex images including cube maps, volume maps, and images including custom mip levels. The layout of the internal memory should be:

face 0, mip 0 (top), width x height (x depth)
face 0, mip 1, width/2 x height/2 (x depth/2)
face 0, mip 2, width/4 x height/4 (x depth/4)
.. remaining mips for face 0 ..
face 1, mip 0 (top), width x height (x depth)</li
.. and so on.

Of course, you will never have multiple faces (cube map) and depth too.

Parameters

data	The data pointer
width	Width of image
height	Height of image
depth	Image Depth (in 3d images, numbers of layers, otherwise 1)
format	Pixel Format
autoDelete	If memory associated with this buffer is to be destroyed with the Image object. Note: it's important that if you set this option to true, that you allocated the memory using OGRE_ALLOC_T with a category of MEMCATEGORY_GENERAL to ensure the freeing of memory matches up.
numFaces	The number of faces the image data has inside (6 for cubemaps, 1 otherwise)
numMipMaps	The number of mipmaps the image data has inside

Note: The memory associated with this buffer is NOT destroyed with the Image object, unless autoDelete is set to true.

Remarks: The size of the buffer must be numFaces * PixelUtil::getMemorySize(width, height, depth, format)

◆ loadDynamicImage() [2/2]

Image& Ogre::Image::loadDynamicImage	(	uchar *	data,
		uint32	width,
		uint32	height,
		PixelFormat	format
	)

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

◆ loadRawData() [1/2]

Image& Ogre::Image::loadRawData	(	const DataStreamPtr &	stream,
		uint32	width,
		uint32	height,
		uint32	depth,
		PixelFormat	format,
		size_t	numFaces = `1`,
		uint32	numMipMaps = `0`
	)

Loads raw data from a stream.

See the function loadDynamicImage for a description of the parameters.

Remarks: The size of the buffer must be numFaces * PixelUtil::getMemorySize(width, height, depth, format)

Note

Whilst typically your image is likely to be a simple 2D image, you can define complex images including cube maps and images including custom mip levels. The layout of the internal memory should be:

face 0, mip 0 (top), width x height (x depth)
face 0, mip 1, width/2 x height/2 (x depth/2)
face 0, mip 2, width/4 x height/4 (x depth/4)
.. remaining mips for face 0 ..
face 1, mip 0 (top), width x height (x depth)</li
.. and so on.

Of course, you will never have multiple faces (cube map) and depth too.

◆ loadRawData() [2/2]

Image& Ogre::Image::loadRawData	(	const DataStreamPtr &	stream,
		uint32	width,
		uint32	height,
		PixelFormat	format
	)

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

References Ogre::BLANKSTRING, and Ogre::PF_BYTE_RGBA.

◆ load() [1/2]

Image& Ogre::Image::load	(	const String &	filename,
		const String &	groupName
	)

Loads an image file.

Remarks: This method loads an image into memory. Any format for which an associated ImageCodec is registered can be loaded. This can include complex formats like DDS with embedded custom mipmaps, cube faces and volume textures. The type can be determined by calling getFormat().

Parameters

filename	Name of an image file to load.
groupName	Name of the resource group to search for the image

Note: The memory associated with this buffer is destroyed with the Image object.

◆ load() [2/2]

Image& Ogre::Image::load	(	const DataStreamPtr &	stream,
		const String &	type = `BLANKSTRING`
	)

Loads an image file from a stream.

Remarks: This method works in the same way as the filename-based load method except it loads the image from a DataStream object. This DataStream is expected to contain the encoded data as it would be held in a file. Any format for which an associated ImageCodec is registered can be loaded. This can include complex formats like DDS with embedded custom mipmaps, cube faces and volume textures. The type can be determined by calling getFormat().

Parameters

stream	The source data.
type	The type of the image. Used to decide what decompression codec to use. Can be left blank if the stream data includes a header to identify the data.

See also: Image::load( const String& filename )

◆ loadTwoImagesAsRGBA() [1/2]

Image& Ogre::Image::loadTwoImagesAsRGBA	(	const String &	rgbFilename,
		const String &	alphaFilename,
		const String &	groupName,
		PixelFormat	format = `PF_BYTE_RGBA`
	)

Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha).

Parameters

rgbFilename	Filename of image supplying the RGB channels (any alpha is ignored)
alphaFilename	Filename of image supplying the alpha channel. If a luminance image the single channel is used directly, if an RGB image then the values are converted to greyscale.
groupName	The resource group from which to load the images
format	The destination format

◆ loadTwoImagesAsRGBA() [2/2]

Image& Ogre::Image::loadTwoImagesAsRGBA	(	const DataStreamPtr &	rgbStream,
		const DataStreamPtr &	alphaStream,
		PixelFormat	format = `PF_BYTE_RGBA`,
		const String &	rgbType = `BLANKSTRING`,
		const String &	alphaType = `BLANKSTRING`
	)

Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha).

Parameters

rgbStream	Stream of image supplying the RGB channels (any alpha is ignored)
alphaStream	Stream of image supplying the alpha channel. If a luminance image the single channel is used directly, if an RGB image then the values are converted to greyscale.
format	The destination format
rgbType	The type of the RGB image. Used to decide what decompression codec to use. Can be left blank if the stream data includes a header to identify the data.
alphaType	The type of the alpha image. Used to decide what decompression codec to use. Can be left blank if the stream data includes a header to identify the data.

◆ combineTwoImagesAsRGBA()

Image& Ogre::Image::combineTwoImagesAsRGBA	(	const Image &	rgb,
		const Image &	alpha,
		PixelFormat	format = `PF_BYTE_RGBA`
	)

Utility method to combine 2 separate images into this one, with the first image source supplying the RGB channels, and the second image supplying the alpha channel (as luminance or separate alpha).

Parameters

rgb	Image supplying the RGB channels (any alpha is ignored)
alpha	Image supplying the alpha channel. If a luminance image the single channel is used directly, if an RGB image then the values are converted to greyscale.
format	The destination format

◆ save()

void Ogre::Image::save ( const String & filename )

Save the image as a file.

Remarks: Saving and loading are implemented by back end (sometimes third party) codecs. Implemented saving functionality is more limited than loading in some cases. Particularly DDS file format support is currently limited to true colour or single channel float32, square, power of two textures with no mipmaps. Volumetric support is currently limited to DDS files.

◆ encode()

DataStreamPtr Ogre::Image::encode ( const String & formatextension )

Encode the image and return a stream to the data.

Parameters

formatextension An extension to identify the image format to encode into, e.g. "jpg" or "png"

◆ getData() [1/2]

uchar* Ogre::Image::getData ( void )

Returns a pointer to the internal image buffer.

Remarks: Be careful with this method. You will almost certainly prefer to use getPixelBox, especially with complex images which include many faces or custom mipmaps.

◆ getData() [2/2]

const uchar* Ogre::Image::getData ( ) const

Returns a const pointer to the internal image buffer.

Remarks: Be careful with this method. You will almost certainly prefer to use getPixelBox, especially with complex images which include many faces or custom mipmaps.

◆ getSize()

size_t Ogre::Image::getSize ( ) const

Returns the size of the data buffer.

◆ getNumMipmaps()

uint32 Ogre::Image::getNumMipmaps ( ) const

Returns the number of mipmaps contained in the image.

◆ hasFlag()

bool Ogre::Image::hasFlag ( const ImageFlags imgFlag ) const

Returns true if the image has the appropriate flag set.

◆ getWidth()

uint32 Ogre::Image::getWidth ( void ) const

Gets the width of the image in pixels.

◆ getHeight()

uint32 Ogre::Image::getHeight ( void ) const

Gets the height of the image in pixels.

◆ getDepth()

uint32 Ogre::Image::getDepth ( void ) const

Gets the depth of the image.

◆ getNumFaces()

size_t Ogre::Image::getNumFaces ( void ) const

Get the number of faces of the image.

This is usually 6 for a cubemap, and 1 for a normal image.

◆ getRowSpan()

size_t Ogre::Image::getRowSpan ( void ) const

Gets the physical width in bytes of each row of pixels.

◆ getFormat()

PixelFormat Ogre::Image::getFormat ( ) const

Returns the image format.

◆ getBPP()

uchar Ogre::Image::getBPP ( ) const

Returns the number of bits per pixel.

◆ getHasAlpha()

bool Ogre::Image::getHasAlpha ( ) const

Returns true if the image has an alpha component.

◆ applyGamma()

static void Ogre::Image::applyGamma	(	uchar *	buffer,
		Real	gamma,
		size_t	size,
		uchar	bpp
	)

static

Does gamma adjustment.

Note: Basic algo taken from Titan Engine, copyright (c) 2000 Ignacio Castano Iguado

◆ getColourAt()

ColourValue Ogre::Image::getColourAt	(	size_t	x,
		size_t	y,
		size_t	z
	)		const

Get colour value from a certain location in the image.

The z coordinate is only valid for cubemaps and volume textures. This uses the first (largest) mipmap.

◆ setColourAt()

void Ogre::Image::setColourAt	(	ColourValue const &	cv,
		size_t	x,
		size_t	y,
		size_t	z
	)

Set colour value at a certain location in the image.

The z coordinate is only valid for cubemaps and volume textures. This uses the first (largest) mipmap.

◆ getPixelBox()

PixelBox Ogre::Image::getPixelBox	(	size_t	face = `0`,
		size_t	mipmap = `0`
	)		const

Get a PixelBox encapsulating the image data of a mipmap.

◆ freeMemory()

void Ogre::Image::freeMemory ( )

Delete all the memory held by this image, if owned by this image (not dynamic)

◆ scale()

static void Ogre::Image::scale	(	const PixelBox &	src,
		const PixelBox &	dst,
		Filter	filter = `FILTER_BILINEAR`
	)

static

Scale a 1D, 2D or 3D image volume.

Parameters

src	PixelBox containing the source pointer, dimensions and format
dst	PixelBox containing the destination pointer, dimensions and format
filter	Which filter to use

Remarks: This function can do pixel format conversion in the process.

Note: dst and src can point to the same PixelBox object without any problem

◆ resize()

void Ogre::Image::resize	(	ushort	width,
		ushort	height,
		Filter	filter = `FILTER_BILINEAR`
	)

Resize a 2D image, applying the appropriate filter.

◆ calculateSize()

static size_t Ogre::Image::calculateSize	(	size_t	mipmaps,
		size_t	faces,
		uint32	width,
		uint32	height,
		uint32	depth,
		PixelFormat	format
	)

static

Static function to calculate size in bytes from the number of mipmaps, faces and the dimensions.

◆ getFileExtFromMagic()

static String Ogre::Image::getFileExtFromMagic ( DataStreamPtr stream )

static

Static function to get an image type string from a stream via magic numbers.

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

OgreImage.h

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ Filter

Constructor & Destructor Documentation

◆ Image() [1/2]

◆ Image() [2/2]

◆ ~Image()

Member Function Documentation

◆ operator=()

◆ flipAroundY()

◆ flipAroundX()

◆ loadDynamicImage() [1/2]

◆ loadDynamicImage() [2/2]

◆ loadRawData() [1/2]

◆ loadRawData() [2/2]

◆ load() [1/2]

◆ load() [2/2]

◆ loadTwoImagesAsRGBA() [1/2]

◆ loadTwoImagesAsRGBA() [2/2]

◆ combineTwoImagesAsRGBA()

◆ save()

◆ encode()

◆ getData() [1/2]

◆ getData() [2/2]

◆ getSize()

◆ getNumMipmaps()

◆ hasFlag()

◆ getWidth()

◆ getHeight()

◆ getDepth()

◆ getNumFaces()

◆ getRowSpan()

◆ getFormat()

◆ getBPP()

◆ getHasAlpha()

◆ applyGamma()

◆ getColourAt()

◆ setColourAt()

◆ getPixelBox()

◆ freeMemory()

◆ scale()

◆ resize()

◆ calculateSize()

◆ getFileExtFromMagic()