OGRE  13.6 Object-Oriented Graphics Rendering Engine
Ogre::Volume::Source Class Referenceabstract

Abstract class defining the density function. More...

#include <OgreVolumeSource.h>

Inheritance diagram for Ogre::Volume::Source:

Public Member Functions

virtual ~Source (void)
Destructor. More...

bool getFirstRayIntersection (const Ray &ray, Vector3 &result, Real scale=(Real) 1.0, size_t maxIterations=5000, Real maxDistance=(Real) 10000.0) const
Gets the first intersection of a ray with the volume. More...

virtual Real getValue (const Vector3 &position) const =0
Gets the density value at a specific position. More...

virtual Vector4 getValueAndGradient (const Vector3 &position) const =0
Gets the density value and gradient at a specific position. More...

Real getVolumeSpaceToWorldSpaceFactor (void) const
Gets a factor to come from volume coordinate to world coordinate. More...

void serialize (const Vector3 &from, const Vector3 &to, float voxelWidth, const String &file)
Serializes a volume source to a discrete grid file with deflated compression. More...

void serialize (const Vector3 &from, const Vector3 &to, float voxelWidth, Real maxClampedAbsoluteDensity, const String &file)
Same as the other serialize function but with a user definable maximum absolute density value. More...

Static Public Attributes

static const size_t SERIALIZATION_CHUNK_SIZE
The amount of items being written as one chunk during serialization. More...

static const uint32 VOLUME_CHUNK_ID
The id of volume files. More...

static const uint16 VOLUME_CHUNK_VERSION
The version of volume files. More...

Detailed Description

Abstract class defining the density function.

◆ ~Source()

 virtual Ogre::Volume::Source::~Source ( void )
virtual

Destructor.

Member Function Documentation

 virtual Vector4 Ogre::Volume::Source::getValueAndGradient ( const Vector3 & position ) const
pure virtual

Gets the density value and gradient at a specific position.

Parameters
 position The position.
Returns
A vector with x, y, z containing the gradient and w containing the density.

◆ getValue()

 virtual Real Ogre::Volume::Source::getValue ( const Vector3 & position ) const
pure virtual

Gets the density value at a specific position.

Parameters
 position The position.
Returns
The density.

◆ serialize() [1/2]

 void Ogre::Volume::Source::serialize ( const Vector3 & from, const Vector3 & to, float voxelWidth, const String & file )

Serializes a volume source to a discrete grid file with deflated compression.

To achieve better compression, all density values are clamped within a maximum absolute value of (to - from).length() / 16.0. The values are scanned in this inner-loop-order: z, x, y. y last because there is usually the least isosurface intersection to be expected in the use case of terrain and so more often the maximum density value hit. The values are written as 16 Bit floats to save space. Note that this process is not lossless, the tradeoff is between accuracy of the source-reproduction (smaller voxelWidth) and smaller filesize (bigger voxelWidth).

Parameters
 from The start point to scan the volume. to The end point to scan the volume. voxelWidth The width of a single cube in the density grid. file The file to write the grid to.

◆ serialize() [2/2]

 void Ogre::Volume::Source::serialize ( const Vector3 & from, const Vector3 & to, float voxelWidth, Real maxClampedAbsoluteDensity, const String & file )

Same as the other serialize function but with a user definable maximum absolute density value.

Parameters
 from The start point to scan the volume. to The end point to scan the volume. voxelWidth The width of a single cube in the density grid. maxClampedAbsoluteDensity The maximum absolute density value to be written into the file, influencing the compression rate. file The file to write the grid to.

◆ getFirstRayIntersection()

 bool Ogre::Volume::Source::getFirstRayIntersection ( const Ray & ray, Vector3 & result, Real scale = (Real) 1.0, size_t maxIterations = 5000, Real maxDistance = (Real) 10000.0 ) const

Gets the first intersection of a ray with the volume.

If you are using this together with the VolumeChunk: Beware of the possible scaling or other transformations you did on the Chunk! Do the inverse first on the ray origin. Example of a scaling with the factor 10: ray.setOrigin(ray.getOrigin() / (Real)10.0);

Parameters
 ray The ray. result Will hold the intersection point if there is an intersection. scale The scaling of the volume compared to the world. maxIterations The maximum amount of iterations on the ray before giving up. maxDistance The maximum distance of the intersection point.

◆ getVolumeSpaceToWorldSpaceFactor()

 Real Ogre::Volume::Source::getVolumeSpaceToWorldSpaceFactor ( void ) const

Gets a factor to come from volume coordinate to world coordinate.

Returns
The factor, 1.0 in the default implementation.

◆ VOLUME_CHUNK_ID

 const uint32 Ogre::Volume::Source::VOLUME_CHUNK_ID
static

The id of volume files.

◆ VOLUME_CHUNK_VERSION

 const uint16 Ogre::Volume::Source::VOLUME_CHUNK_VERSION
static

The version of volume files.

◆ SERIALIZATION_CHUNK_SIZE

 const size_t Ogre::Volume::Source::SERIALIZATION_CHUNK_SIZE
static

The amount of items being written as one chunk during serialization.

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