vtHeightField3d Class Reference

Inheritance diagram for vtHeightField3d:

Public Member Functions
void	Initialize (const LinearUnits units, const DRECT &earthextents, float fMinHeight, float fMaxHeight)
virtual void	SetEarthExtents (const DRECT &ext)
virtual bool	FindAltitudeAtPoint (const FPoint3 &p3, float &fAltitude, bool bTrue=false, int iCultureFlags=0, FPoint3 *vNormal=NULL) const =0
virtual bool	CastRayToSurface (const FPoint3 &point, const FPoint3 &dir, FPoint3 &result) const =0
	Find the intersection point of a ray with the heightfield.
int	PointIsAboveTerrain (const FPoint3 &p) const
bool	ConvertEarthToSurfacePoint (const DPoint2 &epos, FPoint3 &p3, int iCultureFlags=0, bool bTrue=false) const
bool	ContainsWorldPoint (float x, float z) const
void	GetCenter (FPoint3 &center) const
void	SetCulture (CultureExtension *ext)
float	LineOnSurface (const DLine2 &line, float fSpacing, float fOffset, bool bInterp, bool bCurve, bool bTrue, FLine3 &output)
Public Member Functions inherited from vtHeightField
void	Initialize (const DRECT &extents, float fMinHeight, float fMaxHeight)
virtual bool	FindAltitudeOnEarth (const DPoint2 &p, float &fAltitude, bool bTrue=false) const =0
bool	ContainsEarthPoint (const DPoint2 &p, bool bInclusive=false) const
DRECT &	GetEarthExtents ()
const DRECT &	GetEarthExtents () const
void	GetHeightExtents (float &fMinHeight, float &fMaxHeight) const

Public Attributes
FRECT	m_WorldExtents
LocalCS	m_LocalCS

Protected Member Functions
void	UpdateWorldExtents ()

Protected Attributes
float	m_fDiagonalLength
CultureExtension *	m_pCulture
Protected Attributes inherited from vtHeightField
float	m_fMinHeight
float	m_fMaxHeight
DRECT	m_EarthExtents

Detailed Description

This class extents vtHeightField with the abilty to operate in 'world' coordinates, that is, an artificial meters-based 3D coordinate system which is much better suited for many tasks than trying to operate directly on the raw 2D 'earth' coordinates.

Member Function Documentation

bool vtHeightField3d::ContainsWorldPoint	(	float	x,
		float	z
	)		const

Tests whether a given point is within the current terrain

bool vtHeightField3d::ConvertEarthToSurfacePoint	(	const DPoint2 &	epos,
		FPoint3 &	p3,
		int	iCultureFlags = 0,
		bool	bTrue = false
	)		const

Converts a earth coordinate (project or geographic) to a world coordinate on the surface of the heightfield.

Returns

true if successful, false if there was no elevation at that point.

virtual bool vtHeightField3d::FindAltitudeAtPoint ( const FPoint3 &  p3, float &  fAltitude, bool  bTrue = false, int  iCultureFlags = 0, FPoint3 *  vNormal = NULL  ) const

pure virtual

Given a point in world coordinates, determine the elevation at that point.

Parameters

p3	The point to test. Only the X and Z values are used.
fAltitude	The resulting elevation at that point, by reference.
bTrue	True to test true elevation. False to test the displayed elevation (possibly exaggerated.)
iCultureFlags	Pass 0 to test only the heightfield itself, non-zero to test any culture objects which may be sitting on the heightfield. Values include: CE_STRUCTURES Test structures on the ground. CE_ROADS Test roads on the ground. CE_ALL Test everything on the ground.
vNormal	If you supply a pointer to a vector, it will be set to the upward-pointing surface normal at the ground point.

Returns

true if successful, false if there was nothing found at that point.

Implemented in vtElevationGrid, and vtTin.

float vtHeightField3d::LineOnSurface	(	const DLine2 &	line,
		float	fSpacing,
		float	fOffset,
		bool	bInterp,
		bool	bCurve,
		bool	bTrue,
		FLine3 &	output
	)

Create a set of points on the heightfield for a 2D polyline by draping the point onto the surface.

Parameters

line	The 2D line to drape, in Earth coordinates.
fSpacing	The approximate spacing of the surface tessellation, used to decide how finely to tessellate the line.
fOffset	An offset to elevate each point in the resulting geometry, useful for keeping it visibly above the ground.
bInterp	True to interpolate between the vertices of the input line. This is generally desirable when the ground is much more finely spaced than the input line.
bCurve	True to interpret the vertices of the input line as control points of a curve. The created geometry will consist of a draped line which passes through the control points.
bTrue	True to use the true elevation of the terrain, ignoring whatever scale factor is being used to exaggerate elevation for display.
output	Received the points.

Returns

The approximate length of the resulting 3D polyline.

int vtHeightField3d::PointIsAboveTerrain

(

const FPoint3 &

p

)

const

Returns

0 if below terrain, 1 if above terrain, -1 if off terrain.

void vtHeightField3d::SetEarthExtents ( const DRECT &  ext )

virtual

Set the geographic extents of the grid.

Reimplemented from vtHeightField.

Reimplemented in vtHeightFieldGrid3d.