A heightfield. A uniform discretization of space which supports queries on height and normal of field. More...

#include <HeightField.h>

Inheritance diagram for Terrain::HeightField:

Public Member Functions
	HeightField (const std::string &fileName)
	Constructor. More...

bool	initialize (const std::string &imgName, float cellSize, float vertScale, float xpos, float zpos, float smoothParam=0.f)
	Initialize the height field. The heightfield is positioned with the "minimum" corner at the origin and extending into the first quadrant of the x-z plane based on cell size and image resolution. More...

virtual const std::string &	getLabel () const
	Returns a unique resource label to be used to identify different resource types which use the same underlying file data.

void	computeNormals ()
	Given the height field information, computes normals for the data.

float	getHeightAt (float x, float y) const
	Returns the height at the given world position. If the world position lies outside of the domain of the height field, the height at the nearest cell center is returned. More...

Vector3	getNormalAt (float x, float y) const
	Returns the height field normal at the given world position. If the world position lies outside of the domain of the height field, the normal of the nearest cell center is returned. More...

float	getHeightAtCell (int x, int y) const
	Returns the height at the given cell center. The behavior is undefined if the indices fall outside the array of cell values. More...

Vector3	getNormalAtCell (int x, int y) const
	Returns the normal at the given cell center. The behavior is undefined if the indices fall outside the array of cell values. More...

int	getW () const
	Return the number of cells in the width direction of the field. More...

int	getH () const
	Return the number of cells in the height direction of the field. More...

float	getCellSize () const
	Returns the cellSize of the height field. More...

float	getCornerX () const
	Returns the x-position of the mininum corner of the grid. More...

float	getCornerY () const
	Returns the y-position of the mininum corner of the grid. More...

Static Public Member Functions
static Resource *	load (const std::string &fileName)
	Parses a graph definition and returns a pointer to it. More...

Static Public Attributes
static const std::string	LABEL
	The unique label for this data type to be used with resource management.

Protected Member Functions
	~HeightField ()
	Destructor.

void	smoothElevation (float smooth)
	Smooth the elevation using a symmetric 2D gaussian kernel. More...

Protected Attributes
float	_cellSize
	The size of a cell in the heightfield (in world coordinates)

int	_W
	The number of cells in the width (x) direction.

int	_H
	The number of cells in the height (z) direction.

float **	_heightMap
	The data for the height field.

Vector3 **	_normalMap
	The data for the normals of the height field.

float	_xpos
	The x-position of the minimum corner of the heightfield.

float	_ypos
	The y-position of the minimum corner of the heightfield.

Detailed Description

A heightfield. A uniform discretization of space which supports queries on height and normal of field.

Constructor & Destructor Documentation

Terrain::HeightField::HeightField ( const std::string & fileName )

Constructor.

Parameters

fileName The height field specification file used to define the height field.

Member Function Documentation

float Terrain::HeightField::getCellSize ( ) const

inline

Returns the cellSize of the height field.

Returns: The size of the side of the square cell.

float Terrain::HeightField::getCornerX ( ) const

inline

Returns the x-position of the mininum corner of the grid.

Returns: The minimum corner of the grid.

float Terrain::HeightField::getCornerY ( ) const

inline

Returns the y-position of the mininum corner of the grid.

Returns: The minimum corner of the grid.

int Terrain::HeightField::getH ( ) const

inline

Return the number of cells in the height direction of the field.

Returns: The number of cells in the height (y) direction.

float Terrain::HeightField::getHeightAt	(	float	x,
		float	y
	)		const

Returns the height at the given world position. If the world position lies outside of the domain of the height field, the height at the nearest cell center is returned.

Parameters

x	The position along the x-axis.
y	The position along the y-axis.

Returns: The height at the position (x, y).

float Terrain::HeightField::getHeightAtCell	(	int	x,
		int	y
	)		const

Returns the height at the given cell center. The behavior is undefined if the indices fall outside the array of cell values.

Parameters

x	The index along the x-axis..
y	The index along the y-axis.

Returns: The height at the cell center with indices[ x, y ].

Vector3 Terrain::HeightField::getNormalAt	(	float	x,
		float	y
	)		const

Returns the height field normal at the given world position. If the world position lies outside of the domain of the height field, the normal of the nearest cell center is returned.

Parameters

x	The position along the x-axis.
y	The position along the y-axis.

Returns: The normal at the position (x, y).

Vector3 Terrain::HeightField::getNormalAtCell	(	int	x,
		int	y
	)		const

Returns the normal at the given cell center. The behavior is undefined if the indices fall outside the array of cell values.

Parameters

x	The index along the x-axis..
y	The index along the y-axis.

Returns: The normal at the cell center with indices[ x, y ].

int Terrain::HeightField::getW ( ) const

inline

Return the number of cells in the width direction of the field.

Returns: The number of cells in the width (x) direction.

bool Terrain::HeightField::initialize	(	const std::string &	imgName,
		float	cellSize,
		float	vertScale,
		float	xpos,
		float	zpos,
		float	smoothParam = `0.f`
	)

Initialize the height field. The heightfield is positioned with the "minimum" corner at the origin and extending into the first quadrant of the x-z plane based on cell size and image resolution.

Parameters

imgName	The image file used to define the height field.
cellSize	The size of each cell in the image in world coordinates.
vertScale	The values of the image (in the range [0, 255] are normalized to the range [0, 1] and then multiplied by this vertical scale.
xpos	The x-coordinate of the terrain's origin
zpos	The z-coordinate of the terrain's origin
smoothParam	The smoothing parameter for the elevation values. It is interpreted as the standard deviation of a 2D symmetric gaussian kernel. If zero, no smoothing will be performed.

Returns: true if initalization was successful

Resource * Terrain::HeightField::load ( const std::string & fileName )

static

Parses a graph definition and returns a pointer to it.

This function works in conjunction with the ResourceManager. That is why it returns a pointer, not to a Graph, but to a Resource. The ResourceManager uses it to load and instantiate Graph instances.

Parameters

fileName The path to the file containing the VectorField definition.

Returns: A pointer to the new Graph (if the file is valid), NULL if invalid.

void Terrain::HeightField::smoothElevation ( float smooth )

protected

Smooth the elevation using a symmetric 2D gaussian kernel.

Parameters

smooth The smoothing parameter (standard deviation) of the kernel.

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

src/Plugins/Terrain/HeightField.h
src/Plugins/Terrain/HeightField.cpp

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation