vtTin Class Reference

Inheritance diagram for vtTin:

List of all members.

Public Member Functions
unsigned int	NumVerts () const
unsigned int	NumTris () const
void	AddVert (const DPoint2 &p, float z)
void	AddVert (const DPoint2 &p, float z, FPoint3 &normal)
void	AddTri (int v1, int v2, int v3, int surface_type=-1)
void	RemVert (int v)
void	RemTri (int t)
bool	Read (const char *fname)
bool	ReadHeader (const char *fname)
bool	ReadBody (const char *fname)
bool	Write (const char *fname, bool progress_callback(int)=NULL) const
bool	ReadDXF (const char *fname, bool progress_callback(int)=NULL)
bool	ReadADF (const char *fname, bool progress_callback(int)=NULL)
bool	ReadGMS (const char *fname, bool progress_callback(int)=NULL)
void	FreeData ()
unsigned int	AddSurfaceType (const vtString &surface_texture, bool bTiled=false)
void	SetSurfaceType (int iTri, int surface_type)
bool	ComputeExtents ()
void	Offset (const DPoint2 &p)
void	Scale (float fFactor)
void	VertOffset (float fAmount)
bool	ConvertProjection (const vtProjection &proj_new)
virtual bool	FindAltitudeOnEarth (const DPoint2 &p, float &fAltitude, bool bTrue=false) const
virtual bool	FindAltitudeAtPoint (const FPoint3 &p3, float &fAltitude, bool bTrue=false, int iCultureFlags=0, FPoint3 *vNormal=NULL) const
bool	CastRayToSurface (const FPoint3 &point, const FPoint3 &dir, FPoint3 &result) const
	Find the intersection point of a ray with the heightfield.
void	CleanupClockwisdom ()
int	RemoveUnusedVertices ()
double	GetTriMaxEdgeLength (int iTri) const
void	MergeSharedVerts (bool progress_callback(int)=NULL)
bool	HasVertexNormals ()
int	RemoveTrianglesBySegment (const DPoint2 &ep1, const DPoint2 &ep2)
void	SetupTriangleBins (int bins, bool progress_callback(int)=NULL)
int	MemoryNeededToLoad () const
Public Attributes
vtProjection	m_proj
Protected Member Functions
bool	TestTriangle (int tri, const DPoint2 &p, float &fAltitude) const
bool	_ReadTin (FILE *fp)
bool	_ReadTinHeader (FILE *fp)
bool	_ReadTinBody (FILE *fp)
bool	_ReadTinOld (FILE *fp)
void	_UpdateIndicesInInBin (int bin)
void	_CompareBins (int bin1, int bin2)
Protected Attributes
DLine2	m_vert
vtArray< float >	m_z
vtArray< int >	m_tri
FLine3	m_vert_normal
vtArray< int >	m_surfidx
vtStringArray	m_surftypes
vtArray< bool >	m_surftype_tiled
int *	m_bReplace
Bin *	m_vertbin
Bin *	m_tribin
BinArray *	m_trianglebins
DPoint2	m_BinSize
int	m_file_data_start
int	m_file_verts
int	m_file_tris

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Detailed Description

This class represents a TIN, a 'triangulated irregular network'. A TIN consists of a set of vertices connected by triangles with no regularity. However this class does expect to operate on a particular kind of TIN, specifically a heightfield TIN.

The triangles are defined by indices into the vertex array, so this is an "indexed TIN".

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Member Function Documentation

void vtTin::CleanupClockwisdom

(

)

Test each triangle for clockwisdom, fix if needed. The result should be a TIN with consistent vertex ordering, such that all face normals point up rather than down, that is, counter-clockwise.

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

Implements vtHeightField3d.

double vtTin::GetTriMaxEdgeLength

(

int

iTri

)

const

Return the length of the longest edge of a specific triangle.

void vtTin::MergeSharedVerts

(

bool

progress_callbackint = NULL

)

Combine all vertices which are at the same location. By removing these redundant vertices, the mesh will consume less space in memory and on disk.

bool vtTin::Read

(

const char *

fname

)

Read the TIN from a file. This can either be an old-style or new-style .tin format (custom VTP format)

bool vtTin::ReadBody

(

const char *

fname

)

Read the TIN body from a file.

bool vtTin::ReadDXF	(	const char *	fname,
		bool	progress_callbackint = NULL
	)

Attempt to read TIN data from a DXF file.

bool vtTin::ReadHeader

(

const char *

fname

)

Read the TIN header from a file.

int vtTin::RemoveTrianglesBySegment	(	const DPoint2 &	ep1,
		const DPoint2 &	ep2
	)

Remove all the triangles of this TIN which intersect a given line segment.

Parameters:

ep1,ep2

The endpoints of the line segment.

Returns:

The number of triangles removed.

int vtTin::RemoveUnusedVertices

(

)

Because the TIN triangles refer to their vertices by index, it's possible to have some vertices which are not referenced. Find and remove those vertices.

Returns:

The number of unused vertices removed.

void vtTin::SetupTriangleBins	(	int	bins,
		bool	progress_callbackint = NULL
	)

If you are going to do a large number of height-testing of this TIN (with FindAltitudeOnEarth), call this method once first to set up a series of bins which greatly speed up testing.

Parameters:

bins	Number of bins per dimension, e.g. a value of 50 produces 50*50=2500 bins. More bins produces faster height-testing with the only tradeoff being a small amount of RAM per bin.
progress_callback	If supplied, this function will be called back with a value of 0 to 100 as the operation progresses.

bool vtTin::Write	(	const char *	fname,
		bool	progress_callbackint = NULL
	)		const

Write the TIN to a new-style .tin file (custom VTP format).