SoSFImage3 Class Reference
[Fields]

Field containing a 3D image. More...

#include <Inventor/fields/SoSFImage3.h>

Inheritance diagram for SoSFImage3:

Public Types
enum	CopyPolicy { COPY = 0, NO_COPY = 1, NO_COPY_AND_DELETE = 2, NO_COPY_AND_FREE = 3 }
Public Member Functions
virtual SoType	getTypeId () const
const SoSFImage3 &	operator= (const SoSFImage3 &f)
	SoSFImage3 ()
virtual	~SoSFImage3 ()
const unsigned char *	getValue (SbVec3s &size, int &nc) const
SoBufferObject *	getBufferObject (SbVec3s &size, int &nc) const
void	setValue (const SbVec3s &size, int nc, unsigned char *bytes, CopyPolicy copy=COPY)
void	setValue (const SbVec3s &size, int nc, SoBufferObject *bufferObject, CopyPolicy copy=COPY)
void	setSubValue (const SbVec3s &subSize, const SbVec3s &offset, unsigned char *bytes, CopyPolicy copy=COPY)
void	setSubValues (const SbVec3s subSizes, const SbVec3s offsets, int num, unsigned char **bytes, CopyPolicy copy=COPY)
int	operator== (const SoSFImage3 &f) const
int	operator!= (const SoSFImage3 &f) const
unsigned char *	startEditing (SbVec3s &size, int &nc)
void	finishEditing ()
unsigned char *	getSubTexture (int index, SbVec3s &size, SbVec3s &offset)
SbBool	hasSubTextures (int &numSubTextures)
void	setNeverWrite (SbBool neverWrite)
SbBool	isNeverWrite ()
SoBufferObject *	getBufferObject () const
Static Public Member Functions
static SoType	getClassTypeId ()

Detailed Description

Field containing a 3D image.

A field containing a three-dimensional image. A three-dimensional image can be thought of as a sequence of two-dimensional image "slices."

Images can be grayscale (intensity), grayscale with transparency information, RGB, or RGB with transparency. Each component of the image (intensity, red, green, blue or transparency (alpha)) can have an unsigned one-byte value from 0 to 255.

Values are returned as arrays of unsigned chars. The image is stored in this array starting at the bottom left front corner of the image with the intensity or red component of that pixel, followed by either the alpha, the green and blue, or the green, blue and alpha components (depending on the number of components in the image). The next value is the first component of the next pixel to the right.

SoSFImage3s are written to file as four integers representing the width, height, depth and number of components in the image, followed by width*height*depth hexadecimal values representing the pixels in the image, separated by whitespace. A one-component image will have one-byte hexadecimal values representing the intensity of the image. For example, 0xFF is full intensity, 0x00 is no intensity. A two-component image puts the intensity in the first (high) byte and the transparency in the second (low) byte. Pixels in a three-component image have the red component in the first (high) byte, followed by the green and blue components (so 0xFF0000 is red). Four-component images put the transparency byte after red/green/blue (so 0x0000FF80 is semi-transparent blue). Note: each pixel is actually read as a single unsigned number, so a 3-component pixel with value "0x0000FF" can also be written as "0xFF" or "255" (decimal).

For example,

      1 2 3 1 0xFF 0x00 0x00 0xFF 0xFF 0x00

is a 1 pixel wide by 2 pixel high by 3 pixel deep grayscale image, with the bottom pixel white and the top pixel black in the first (front-most) slice. In the second slice the bottom pixel is black and the top pixel is white. And:

      2 4 3 3 0xFF0000 0xFF00 0 0 0 0 0xFFFFFF 0xFFFF00 ...

is a 2 pixel wide by 4 pixel high by 3 pixel deep RGB image, with the bottom left pixel red, the bottom right pixel green, the two middle rows of pixels black, the top left pixel white, and the top right pixel yellow in the first slice. Subsequent slices are not shown.

Member Enumeration Documentation

enum SoSFImage3::CopyPolicy

SoSFImage3 may be manipulating some large amounts of memory.

It is therefore convienent to be able to set the memory usage policy dynamically (copying a small 256x256x256 image with only 8 bits color already takes 16MB). By default, the memory policy is COPY, which is consistent with other OIV fields. The most likely to be efficient is NO_COPY. See also setNeverWrite.

Enumerator:

COPY	Open Inventor will make a copy of the data (default).
NO_COPY	Passed buffer used , user will delete.
NO_COPY_AND_DELETE	Passed buffer used, SoSFImage3 will delete . Use this if memory is allocated with "new".
NO_COPY_AND_FREE	Passed buffer used, SoSFImage3 will free . Use this if memory is allocated with "malloc".

Constructor & Destructor Documentation

SoSFImage3::SoSFImage3 ( )

Default constructor.

virtual SoSFImage3::~SoSFImage3 ( ) [virtual]

Destructor.

Member Function Documentation

void SoSFImage3::finishEditing ( )

These methods can be used to efficiently edit the values in an image field.

startEditing() returns the size of the image in the size and nc arguments; writing past the end of the array returned is a good way to cause hard-to-find core dumps.

Avoid copying the values in/out, if you are just changing the bytes and not changing the dimensions of the image. This is equivalent to getValue(), but returns a pointer you can change.Using startEditing() allows subtexturing, which is a more efficient way of doing texture modification.

SoBufferObject * SoSFImage3::getBufferObject ( ) const [inline]

SoBufferObject* SoSFImage3::getBufferObject	(	SbVec3s &	size,
		int &	nc
	)			const

Returns the pixels in the image as a buffer object.

The size and nc arguments are filled in with the dimensions of the image and the number of components in the image; the number of bytes in the array returned will be size [0]* size [1]* size [2]* nc .

static SoType SoSFImage3::getClassTypeId ( ) [static]

Returns the type identifier for this class.

Reimplemented from SoSField.

unsigned char* SoSFImage3::getSubTexture	(	int	index,
		SbVec3s &	size,
		SbVec3s &	offset
	)

Returns a buffer to a given subTexture set by setSubValue or setSubValues.

These two methods append subTextures to a list. Also returns the size of the subtexture and the offset from the beginning of the image of the requested subImage.

virtual SoType SoSFImage3::getTypeId ( ) const [virtual]

Returns the type identifier for this specific instance.

Implements SoTypedObject.

const unsigned char* SoSFImage3::getValue	(	SbVec3s &	size,
		int &	nc
	)			const

Returns the pixels in the image as an array of unsigned chars.

The size and nc arguments are filled in with the dimensions of the image and the number of components in the image; the number of bytes in the array returned will be size [0]* size [1]* size [2]* nc .

SbBool SoSFImage3::hasSubTextures ( int & numSubTextures )

Returns TRUE if subTextures have been defined or FALSE if none have been defined.

Also returns the number of subTextures defined.

SbBool SoSFImage3::isNeverWrite ( ) [inline]

As this field may have to handle large amounts of data and its representation in an .iv file is not very efficient, it is often a good idea not to allow that data to be written out when required by a write action.

By default, the "neverWrite" condition is TRUE.

int SoSFImage3::operator!= ( const SoSFImage3 & f ) const [inline]

Equality/inequality tests.

Reimplemented from SoField.

const SoSFImage3& SoSFImage3::operator= ( const SoSFImage3 & f )

Copy from another field of same type.

int SoSFImage3::operator== ( const SoSFImage3 & f ) const

Equality/inequality tests.

Reimplemented from SoField.

void SoSFImage3::setNeverWrite ( SbBool neverWrite )

As this field may have to handle large amounts of data and its representation in an .iv file is not very efficient, it is often a good idea not to allow that data to be written out when required by a write action.

By default, the "neverWrite" condition is TRUE.

void SoSFImage3::setSubValue	(	const SbVec3s &	subSize,
		const SbVec3s &	offset,
		unsigned char *	bytes,
		CopyPolicy	copy = `COPY`
	)

These methods may be used for subtexturing: instead of replacing the entire texture in texture memory, only parts of it are replaced.

This is much faster and uses less memory. In any case these methods affect the texture in system memory. Note that the sub-images must have the same number of components as the one contained in this object. The texture in texture memory will not actually be modified until the next render traversal.

void SoSFImage3::setSubValues	(	const SbVec3s *	subSizes,
		const SbVec3s *	offsets,
		int	num,
		unsigned char **	bytes,
		CopyPolicy	copy = `COPY`
	)

These methods may be used for subtexturing: instead of replacing the entire texture in texture memory, only parts of it are replaced.

This is much faster and uses less memory. In any case these methods affect the texture in system memory. Note that the sub-images must have the same number of components as the one contained in this object. The texture in texture memory will not actually be modified until the next render traversal.

void SoSFImage3::setValue	(	const SbVec3s &	size,
		int	nc,
		SoBufferObject *	bufferObject,
		CopyPolicy	copy = `COPY`
	)

void SoSFImage3::setValue	(	const SbVec3s &	size,
		int	nc,
		unsigned char *	bytes,
		CopyPolicy	copy = `COPY`
	)

setValue copies the image given to it into internal storage.

See startEditing() for a way of avoiding the copy if you are doing a getValue() followed immediately by a setValue(). Set 'copy' to NO_COPY or NO_COPY_AND_DELETEto pass directly the the image buffer. Otherwise, the buffer 'bytes' will be copied. If copy is set to COPY or NO_COPY_AND_DELETE or NO_COPY_AND_FREE, this object will delete the buffer when required. If a NULL buffer is passed, a new bloc is allocated according to the size and the number of components.

unsigned char* SoSFImage3::startEditing	(	SbVec3s &	size,
		int &	nc
	)

These methods can be used to efficiently edit the values in an image field.

startEditing() returns the size of the image in the size and nc arguments; writing past the end of the array returned is a good way to cause hard-to-find core dumps.

Avoid copying the values in/out, if you are just changing the bytes and not changing the dimensions of the image. This is equivalent to getValue(), but returns a pointer you can change.Using startEditing() allows subtexturing, which is a more efficient way of doing texture modification.

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

Inventor/fields/SoSFImage3.h

SoSFImage3 Class Reference [Fields]

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

SEE ALSO

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

SoSFImage3 Class Reference
[Fields]