Image::BitmapData Class Reference

Retrieves a section of an image as raw pixel data, so it can be read or written to. More...

#include <juce_Image.h>

Classes
class	BitmapDataReleaser
	Used internally by custom image types to manage pixel data lifetime. More...

Public Types
enum	ReadWriteMode { readOnly , writeOnly , readWrite }

Public Member Functions
	BitmapData (Image &image, int x, int y, int w, int h, ReadWriteMode mode)
	BitmapData (const Image &image, int x, int y, int w, int h)
	BitmapData (const Image &image, ReadWriteMode mode)
	~BitmapData ()
uint8 *	getLinePointer (int y) const noexcept
	Returns a pointer to the start of a line in the image.
uint8 *	getPixelPointer (int x, int y) const noexcept
	Returns a pointer to a pixel in the image.
Colour	getPixelColour (int x, int y) const noexcept
	Returns the colour of a given pixel.
void	setPixelColour (int x, int y, Colour colour) const noexcept
	Sets the colour of a given pixel.
Rectangle< int >	getBounds () const noexcept
	Returns the size of the bitmap.

Public Attributes
uint8 *	data
	The raw pixel data, packed according to the image's pixel format.
size_t	size
	The number of valid/allocated bytes after data.
PixelFormat	pixelFormat
	The format of the data.
int	lineStride
	The number of bytes between each line.
int	pixelStride
	The number of bytes between each pixel.
int	width
int	height
std::unique_ptr< BitmapDataReleaser >	dataReleaser

Detailed Description

Retrieves a section of an image as raw pixel data, so it can be read or written to.

You should only use this class as a last resort - messing about with the internals of an image is only recommended for people who really know what they're doing!

A BitmapData object should be used as a temporary, stack-based object. Don't keep one hanging around while the image is being used elsewhere.

Depending on the way the image class is implemented, this may create a temporary buffer which is copied back to the image when the object is deleted, or it may just get a pointer directly into the image's raw data.

You can use the stride and data values in this class directly, but don't alter them! The actual format of the pixel data depends on the image's format - see Image::getFormat(), and the PixelRGB, PixelARGB and PixelAlpha classes for more info.

Member Enumeration Documentation

ReadWriteMode

enum Image::BitmapData::ReadWriteMode

Enumerator
readOnly
writeOnly
readWrite

Constructor & Destructor Documentation

BitmapData() [1/3]

Image::BitmapData::BitmapData	(	Image &	image,
		int	x,
		int	y,
		int	w,
		int	h,
		ReadWriteMode	mode )

BitmapData() [2/3]

Image::BitmapData::BitmapData	(	const Image &	image,
		int	x,
		int	y,
		int	w,
		int	h )

BitmapData() [3/3]

Image::BitmapData::BitmapData	(	const Image &	image,
		ReadWriteMode	mode )

~BitmapData()

Image::BitmapData::~BitmapData

(

)

Member Function Documentation

getLinePointer()

uint8 * Image::BitmapData::getLinePointer ( int y ) const

noexcept

Returns a pointer to the start of a line in the image.

The coordinate you provide here isn't checked, so it's the caller's responsibility to make sure it's not out-of-range.

References y.

getPixelPointer()

uint8 * Image::BitmapData::getPixelPointer ( int x, int y ) const

noexcept

Returns a pointer to a pixel in the image.

The coordinates you give here are not checked, so it's the caller's responsibility to make sure they're not out-of-range.

References x, and y.

getPixelColour()

Colour Image::BitmapData::getPixelColour ( int x, int y ) const

noexcept

Returns the colour of a given pixel.

For performance reasons, this won't do any bounds-checking on the coordinates, so it's the caller's responsibility to make sure they're within the image's size.

setPixelColour()

void Image::BitmapData::setPixelColour ( int x, int y, Colour colour ) const

noexcept

Sets the colour of a given pixel.

For performance reasons, this won't do any bounds-checking on the coordinates, so it's the caller's responsibility to make sure they're within the image's size.

getBounds()

Rectangle< int > Image::BitmapData::getBounds ( ) const

noexcept

Returns the size of the bitmap.

Member Data Documentation

data

uint8* Image::BitmapData::data

The raw pixel data, packed according to the image's pixel format.

size

size_t Image::BitmapData::size

The number of valid/allocated bytes after data.

May be smaller than "lineStride * height" if this is a section of a larger image.

pixelFormat

PixelFormat Image::BitmapData::pixelFormat

The format of the data.

lineStride

int Image::BitmapData::lineStride

The number of bytes between each line.

pixelStride

int Image::BitmapData::pixelStride

The number of bytes between each pixel.

width

int Image::BitmapData::width

height

int Image::BitmapData::height

dataReleaser

std::unique_ptr<BitmapDataReleaser> Image::BitmapData::dataReleaser

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

• juce_Image.h