#include <SMTerrain.h>

Inheritance diagram for SMTerrain:

Public Member Functions
DTErr	Init (const vtElevationGrid *pGrid, float fZScale)
	initialization

void	DoRender ()

void	DoCulling (const vtCamera *pCam)

float	GetElevation (int iX, int iZ, bool bTrue=false) const

void	GetWorldLocation (int iX, int iZ, FPoint3 &p, bool bTrue=false) const

void	SetVerticalExag (float fExag)

float	GetVerticalExag () const

float	GetQualityConstant () const

Public Member Functions inherited from vtDynTerrainGeom
DTErr	BasicInit (const vtElevationGrid *pGrid)

virtual void	SetPolygonTarget (int iPolygonCount)

int	GetPolygonTarget ()

int	GetNumDrawnTriangles ()

void	SetDetailMaterial (vtMaterial *pApp, float fTiling, float fDistance)

void	EnableDetail (bool bOn)

bool	GetDetail ()

void	SetupTexGen (float fTiling)

void	DisableTexGen ()

void	DoCalcBoundBox (FBox3 &box)

void	DoCull (const vtCamera *pCam)

bool	FindAltitudeOnEarth (const DPoint2 &p, float &fAltitude, bool bTrue=false) const

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

virtual void	SetElevation (int i, int j, float fValue, bool bTrue=false)

void	SetCull (bool bOnOff)

void	CullOnce ()

void	PreRender () const

void	PostRender () const

Public Member Functions inherited from vtDynGeom
int	IsVisible (const FSphere &sphere) const

int	IsVisible (const FPoint3 &point0, const FPoint3 &point1, const FPoint3 &point2, const float fTolerance=0.0f) const

int	IsVisible (const FPoint3 &point, float radius)

bool	IsVisible (const FPoint3 &point) const

void	ApplyMaterial (vtMaterial *mat)

Public Member Functions inherited from vtGeode
vtGeode *	CloneGeode ()

void	CloneFromGeode (const vtGeode *rhs)

void	AddMesh (vtMesh *pMesh, int iMatIdx)

void	RemoveMesh (vtMesh *pMesh)

void	AddTextMesh (vtTextMesh *pMesh, int iMatIdx)

uint	GetNumMeshes () const

vtMesh *	GetMesh (int i) const

vtTextMesh *	GetTextMesh (int i) const

virtual void	SetMaterials (const class vtMaterialArray *mats)

const vtMaterialArray *	GetMaterials () const

vtMaterial *	GetMaterial (int idx)

void	SetMeshMatIndex (vtMesh *pMesh, int iMatIdx)

Public Member Functions inherited from NodeExtension
void	SetEnabled (bool bOn)

bool	GetEnabled () const

void	SetCastShadow (bool b)
	Set this node to cast a shadow, if it is under a vtShadow node. Default is false.

bool	GetCastShadow ()
	Get whether this node casts a shadow.

void	GetBoundSphere (FSphere &sphere, bool bGlobal=false)
	Get the Bounding Sphere of the node.

void	SetOsgNode (osg::Node *n)

Public Member Functions inherited from vtHeightFieldGrid3d
void	Initialize (const LinearUnits units, const DRECT &earthextents, float fMinHeight, float fMaxHeight, int cols, int rows)

virtual void	SetEarthExtents (const DRECT &ext)

bool	CastRayToSurface (const FPoint3 &point, const FPoint3 &dir, FPoint3 &result) const

bool	LineOfSight (const FPoint3 &point1, const FPoint3 &point2) const

DPoint2	GetSpacing () const

FPoint2	GetWorldSpacing () const

void	GetDimensions (int &nColumns, int &nRows) const

int	NumColumns ()

int	NumRows ()

void	EarthToGrid (const DPoint2 &epos, IPoint2 &ipos)

void	WorldToGrid (const FPoint3 &pos, IPoint2 &ipos)

float	GetInterpolatedElevation (double findex_x, double findex_y) const

int	FindNumUnknown ()

bool	ColorDibFromElevation (vtBitmapBase pBM, const ColorMap cmap, int iGranularity, const RGBAi &nodata, bool progress_callback(int)=NULL)

bool	ColorDibFromTable (vtBitmapBase *pBM, std::vector< RGBi > &table, float fMin, float fMax, const RGBAi &nodata, bool progress_callback(int)=NULL)

void	ShadeDibFromElevation (vtBitmapBase *pBM, const FPoint3 &light_dir, float fLightFactor, float fAmbient=0.1f, float fGamma=1.0f, bool bTrue=false, bool progress_callback(int)=NULL)

void	ShadeQuick (vtBitmapBase *pBM, float light_factor, bool bTrue=false, bool progress_callback(int)=NULL)

void	ShadowCastDib (vtBitmapBase *pBM, const FPoint3 &ight_dir, float fLightFactor, float fAmbient, bool progress_callback(int)=NULL)

Public Member Functions inherited from vtHeightField3d
void	Initialize (const LinearUnits units, const DRECT &earthextents, float fMinHeight, float fMaxHeight)

int	PointIsAboveTerrain (const FPoint3 &p) const

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

bool	ContainsWorldPoint (float x, float z)

void	GetCenter (FPoint3 &center)

void	SetCulture (CultureExtension *ext)

Public Member Functions inherited from vtHeightField
void	Initialize (const DRECT &extents, float fMinHeight, float fMaxHeight)

bool	ContainsEarthPoint (const DPoint2 &p, bool bInclusive=false) const

DRECT &	GetEarthExtents ()

const DRECT &	GetEarthExtents () const

void	GetHeightExtents (float &fMinHeight, float &fMaxHeight) const

Static Public Member Functions
static int	MemoryRequired (int iDimension)

Protected Member Functions
void	Init2 ()

void	AllocatePool ()

void	ComputeVariances ()

MathType	ComputeTriangleVariance (int num, int v0, int v1, int va, int level)

void	SetupBlocks ()

void	AdjustQualityConstant ()

void	SplitToBlocks (int num, BinTri *tri, int v0, int v1, int va)

void	SplitIfNeeded (int num, BinTri *tri, int v0, int v1, int va, bool bEntirelyInFrustum, int level)

void	Split (BinTri *tri)

void	Split2 (BinTri *tri)

BinTri *	AllocateBinTri ()

void	RenderSurface ()

void	RenderBlock (BlockPtr block, bool bFans)

bool	BlockIsVisible (BlockPtr block)

void	LoadSingleMaterial ()

void	render_triangle_as_fan (BinTri *pTri, int v0, int v1, int va, bool even, bool right)

void	render_triangle_single (BinTri *pTri, int v0, int v1, int va)

void	flush_buffer (int type)

float	DistanceToTriangle (int num)

Additional Inherited Members
Public Attributes inherited from vtDynTerrainGeom
int	m_iTotalTriangles

int	m_iDrawnTriangles

Protected Attributes inherited from vtDynTerrainGeom
float *	m_fXLookup

float *	m_fZLookup

int	m_iPolygonTarget

bool	m_bCulleveryframe

bool	m_bCullonce

float	m_fDetailTiling

float	m_fDetailDistance

bool	m_bDetailTexture

vtMaterial *	m_pDetailMat

Detailed Description

: The SMTerrain class implements Seumas McNally's algorithm for regular-grid terrain LOD. It was implemented directly from correspondence from the dearly missed Seumas, and is highly similar to the implementation in his game Treadmarks.

: This implementation requires that the input heightfield is a square regular grid of dimension 2^n+1, e.g.. 1025, 2049, or 4097. Storage requirements are around 3-5 bytes/vertex. The data is represented in memory by a regular grid of height values, an implicit binary tree of variance values, and an explicit binary tree of visible faces.

: This is the fastest and most memory-efficient algorithm currently known for terrain rendering with a long viewing distance and an unconstrained viewpoint.

: Usage

Create a new SMTerrain object
Initialize it with a LocalGrid to provide height values
add it to your scene graph
set the desired level detail with SetPolygonTarget()
for a detail texture, call SetDetailMaterial()
let the scene graph API render the terrain for you each frame
Performance Issues

Use of triangle fans can be toggled at runtime, via the m_bUseTriStrips member. In testing, this has shown around a 15% speed increase.

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

D:/job/3kb/gelistirme/umasoft/vtp-src/VTP/TerrainSDK/vtlib/core/SMTerrain.h
D:/job/3kb/gelistirme/umasoft/vtp-src/VTP/TerrainSDK/vtlib/core/SMTerrain.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Usage

Performance Issues