A scene node for displaying terrain using the geo mip map algorithm. More...

#include <nirtcpp/core/engine/ITerrainSceneNode.hpp>

Inheritance diagram for nirt::scene::ITerrainSceneNode:

Collaboration diagram for nirt::scene::ITerrainSceneNode:

Public Member Functions
	ITerrainSceneNode (ISceneNode parent, ISceneManager mgr, s32 id, const core::vector3df &position=core::vector3df(0.0f, 0.0f, 0.0f), const core::vector3df &rotation=core::vector3df(0.0f, 0.0f, 0.0f), const core::vector3df &scale=core::vector3df(1.0f, 1.0f, 1.0f))
	Constructor.

virtual const core::aabbox3d< f32 > &	getBoundingBox () const =0
	Get the bounding box of the terrain.

virtual const core::aabbox3d< f32 > &	getBoundingBox (s32 patchX, s32 patchZ) const =0
	Get the bounding box of a patch.

virtual u32	getIndexCount () const =0
	Get the number of indices currently in the meshbuffer.

virtual IMesh *	getMesh ()=0
	Get pointer to the mesh.

virtual IMeshBuffer *	getRenderBuffer ()=0
	Get pointer to the buffer used by the terrain (most users will not need this)

virtual void	getMeshBufferForLOD (IDynamicMeshBuffer &mb, s32 LOD=0) const =0
	Gets the meshbuffer data based on a specified level of detail.

virtual s32	getIndicesForPatch (core::array< u32 > &indices, s32 patchX, s32 patchZ, s32 LOD=0)=0
	Gets the indices for a specified patch at a specified Level of Detail.

virtual s32	getCurrentLODOfPatches (core::array< s32 > &LODs) const =0
	Populates an array with the CurrentLOD of each patch.

virtual void	setLODOfPatch (s32 patchX, s32 patchZ, s32 LOD=0)=0
	Manually sets the LOD of a patch.

virtual const core::vector3df &	getTerrainCenter () const =0
	Get center of terrain.

virtual f32	getHeight (f32 x, f32 y) const =0
	Get height of a point of the terrain.

virtual void	setCameraMovementDelta (f32 delta)=0
	Sets the movement camera threshold.

virtual void	setCameraRotationDelta (f32 delta)=0
	Sets the rotation camera threshold.

virtual void	setDynamicSelectorUpdate (bool bVal)=0
	Sets whether or not the node should dynamically update its associated selector when the geomipmap data changes.

virtual bool	overrideLODDistance (s32 LOD, f64 newDistance)=0
	Override the default generation of distance thresholds.

virtual void	scaleTexture (f32 scale=1.0f, f32 scale2=0.0f)=0
	Scales the base texture, similar to makePlanarTextureMapping.

virtual bool	loadHeightMap (io::IReadFile *file, video::SColor vertexColor=video::SColor(255, 255, 255, 255), s32 smoothFactor=0)=0
	Initializes the terrain data. Loads the vertices from the heightMapFile.

virtual bool	loadHeightMapRAW (io::IReadFile *file, s32 bitsPerPixel=16, bool signedData=false, bool floatVals=false, s32 width=0, video::SColor vertexColor=video::SColor(255, 255, 255, 255), s32 smoothFactor=0)=0
	Initializes the terrain data. Loads the vertices from the heightMapFile.

virtual void	setFixedBorderLOD (nirt::s32 borderLOD=0)=0
	Force node to use a fixed LOD level at the borders of the terrain.

Public Member Functions inherited from nirt::scene::ISceneNode
	ISceneNode (ISceneNode parent, ISceneManager mgr, s32 id=-1, const core::vector3df &position=core::vector3df(0, 0, 0), const core::vector3df &rotation=core::vector3df(0, 0, 0), const core::vector3df &scale=core::vector3df(1.0f, 1.0f, 1.0f))
	Constructor.

virtual	~ISceneNode ()
	Destructor.

virtual void	OnRegisterSceneNode ()
	This method is called just before the rendering process of the whole scene.

virtual void	OnAnimate (u32 timeMs)
	OnAnimate() is called just before rendering the whole scene.

virtual void	render ()=0
	Renders the node.

virtual const c8 *	getName () const
	Returns the name of the node.

virtual void	setName (const c8 *name)
	Sets the name of the node.

virtual void	setName (const core::stringc &name)
	Sets the name of the node.

virtual const core::aabbox3d< f32 >	getTransformedBoundingBox () const
	Get the axis aligned, transformed and animated absolute bounding box of this node.

virtual void	getTransformedBoundingBoxEdges (core::array< core::vector3d< f32 > > &edges) const

virtual const core::matrix4 &	getAbsoluteTransformation () const
	Get the absolute transformation of the node. Is recalculated every OnAnimate()-call.

virtual core::matrix4	getRelativeTransformation () const
	Returns the relative transformation of the scene node.

virtual bool	isVisible () const
	Returns whether the node should be visible (if all of its parents are visible).

virtual bool	isTrulyVisible () const
	Check whether the node is truly visible, taking into accounts its parents' visibility.

virtual void	setVisible (bool isVisible)
	Sets if the node should be visible or not.

virtual s32	getID () const
	Get the id of the scene node.

virtual void	setID (s32 id)
	Sets the id of the scene node.

virtual void	addChild (ISceneNode *child)
	Adds a child to this scene node.

virtual bool	removeChild (ISceneNode *child)
	Removes a child from this scene node.

virtual void	removeAll ()
	Removes all children of this scene node.

virtual void	remove ()
	Removes this scene node from the scene.

virtual void	addAnimator (ISceneNodeAnimator *animator)
	Adds an animator which should animate this node.

const core::list< ISceneNodeAnimator * > &	getAnimators () const
	Get a list of all scene node animators.

virtual void	removeAnimator (ISceneNodeAnimator *animator)
	Removes an animator from this scene node.

virtual void	removeAnimators ()
	Removes all animators from this scene node.

virtual video::SMaterial &	getMaterial (u32 num)
	Returns the material based on the zero based index i.

virtual u32	getMaterialCount () const
	Get amount of materials used by this scene node.

void	setMaterialFlag (video::E_MATERIAL_FLAG flag, bool newvalue)
	Sets all material flags at once to a new value.

void	setMaterialTexture (u32 textureLayer, video::ITexture *texture)
	Sets the texture of the specified layer in all materials of this scene node to the new texture.

void	setMaterialType (video::E_MATERIAL_TYPE newType)
	Sets the material type of all materials in this scene node to a new material type.

virtual const core::vector3df &	getScale () const
	Gets the scale of the scene node relative to its parent.

virtual void	setScale (const core::vector3df &scale)
	Sets the relative scale of the scene node.

virtual const core::vector3df &	getRotation () const
	Gets the rotation of the node relative to its parent.

virtual void	setRotation (const core::vector3df &rotation)
	Sets the rotation of the node relative to its parent.

virtual const core::vector3df &	getPosition () const
	Gets the position of the node relative to its parent.

virtual void	setPosition (const core::vector3df &newpos)
	Sets the position of the node relative to its parent.

virtual core::vector3df	getAbsolutePosition () const
	Gets the absolute position of the node in world coordinates.

void	setAutomaticCulling (u32 state)
	Set a culling style or disable culling completely.

u32	getAutomaticCulling () const
	Gets the automatic culling state.

void	setUpdateAbsolutePosBehavior (ESCENE_NODE_UPDATE_ABS behavior)
	Set how updateAbsolutePosition calculates the absolute transformation matrix.

ESCENE_NODE_UPDATE_ABS	getUpdateAbsolutePosBehavior () const
	Get how updateAbsolutePosition calculates the absolute transformation matrix.

virtual void	setDebugDataVisible (u32 state)
	Sets if debug data like bounding boxes should be drawn.

u32	isDebugDataVisible () const
	Returns if debug data like bounding boxes are drawn.

void	setIsDebugObject (bool debugObject)
	Sets if this scene node is a debug object.

bool	isDebugObject () const
	Returns if this scene node is a debug object.

const core::list< ISceneNode * > &	getChildren () const
	Returns a const reference to the list of all children.

virtual void	setParent (ISceneNode *newParent)
	Changes the parent of the scene node.

virtual ITriangleSelector *	getTriangleSelector () const
	Returns the triangle selector attached to this scene node.

virtual void	setTriangleSelector (ITriangleSelector *selector)
	Sets the triangle selector of the scene node.

virtual void	updateAbsolutePosition ()
	Updates the absolute tranformation or position based on the relative and the parents transformation.

scene::ISceneNode *	getParent () const
	Returns the parent of this scene node.

virtual ESCENE_NODE_TYPE	getType () const
	Returns type of the scene node.

virtual void	serializeAttributes (io::IAttributes out, io::SAttributeReadWriteOptions options=0) const override
	Writes attributes of the scene node.

virtual void	deserializeAttributes (io::IAttributes in, io::SAttributeReadWriteOptions options=0) override
	Reads attributes of the scene node.

virtual ISceneNode *	clone (ISceneNode newParent=0, ISceneManager newManager=0)
	Creates a clone of this scene node and its children.

virtual ISceneManager *	getSceneManager (void) const
	Retrieve the scene manager for this node.

Public Member Functions inherited from nirt::IReferenceCounted
	IReferenceCounted ()
	Constructor.

virtual	~IReferenceCounted ()
	Destructor.

void	grab () const
	Grabs the object. Increments the reference counter by one.

bool	drop () const
	Drops the object. Decrements the reference counter by one.

s32	getReferenceCount () const
	Get the reference count.

const c8 *	getDebugName () const
	Returns the debug name of the object.

Additional Inherited Members
Protected Member Functions inherited from nirt::scene::ISceneNode
void	cloneMembers (ISceneNode toCopyFrom, ISceneManager newManager)
	A clone function for the ISceneNode members.

void	setSceneManager (ISceneManager *newManager)

Protected Member Functions inherited from nirt::IReferenceCounted
void	setDebugName (const c8 *newName)
	Sets the debug name of the object.

Protected Attributes inherited from nirt::scene::ISceneNode
core::stringc	Name
	Name of the scene node.

core::matrix4	AbsoluteTransformation
	Absolute transformation of the node.

core::vector3df	RelativeTranslation
	Relative translation of the scene node.

core::vector3df	RelativeRotation
	Relative rotation of the scene node.

core::vector3df	RelativeScale
	Relative scale of the scene node.

ISceneNode *	Parent
	Pointer to the parent.

core::list< ISceneNode * >	Children
	List of all children of this node.

core::list< ISceneNodeAnimator * >	Animators
	List of all animator nodes.

ISceneManager *	SceneManager
	Pointer to the scene manager.

ITriangleSelector *	TriangleSelector
	Pointer to the triangle selector.

s32	ID
	ID of the node.

ESCENE_NODE_UPDATE_ABS	UpdateAbsolutePosBehavior
	How updateAbsolutePosition calculates AbsoluteTransformation.

u32	AutomaticCullingState
	Automatic culling state.

u32	DebugDataVisible
	Flag if debug data should be drawn, such as Bounding Boxes.

bool	IsVisible
	Is the node visible?

bool	IsDebugObject
	Is debug object?

Detailed Description

A scene node for displaying terrain using the geo mip map algorithm.

The code for the TerrainSceneNode is based on the Terrain renderer by Soconne and the GeoMipMapSceneNode developed by Spintz. They made their code available for Nirtcpp and allowed it to be distributed under this licence. I only modified some parts. A lot of thanks go to them.

This scene node is capable of very quickly loading terrains and updating the indices at runtime to enable viewing very large terrains. It uses a CLOD (Continuous Level of Detail) algorithm which updates the indices for each patch based on a LOD (Level of Detail) which is determined based on a patch's distance from the camera.

The Patch Size of the terrain must always be a size of ( 2^N+1, i.e. 8+1(9), 16+1(17), etc. ). The MaxLOD available is directly dependent on the patch size of the terrain. LOD 0 contains all of the indices to draw all the triangles at the max detail for a patch. As each LOD goes up by 1 the step taken, in generating indices increases by - 2^LOD, so for LOD 1, the step taken is 2, for LOD 2, the step taken is 4, LOD 3 - 8, etc. The step can be no larger than the size of the patch, so having a LOD of 8, with a patch size of 17, is asking the algorithm to generate indices every 2^8 ( 256 ) vertices, which is not possible with a patch size of 17. The maximum LOD for a patch size of 17 is 2^4 ( 16 ). So, with a MaxLOD of 5, you'll have LOD 0 ( full detail ), LOD 1 ( every 2 vertices ), LOD 2 ( every 4 vertices ), LOD 3 ( every 8 vertices ) and LOD 4 ( every 16 vertices ).

Member Function Documentation

◆ getBoundingBox() [1/2]

virtual const core::aabbox3d< f32 > & nirt::scene::ITerrainSceneNode::getBoundingBox ( ) const

pure virtual

Get the bounding box of the terrain.

Returns: The bounding box of the entire terrain.

Implements nirt::scene::ISceneNode.

◆ getBoundingBox() [2/2]

virtual const core::aabbox3d< f32 > & nirt::scene::ITerrainSceneNode::getBoundingBox	(	s32	patchX,
		s32	patchZ
	)		const

pure virtual

Get the bounding box of a patch.

Returns: The bounding box of the chosen patch.

◆ getCurrentLODOfPatches()

virtual s32 nirt::scene::ITerrainSceneNode::getCurrentLODOfPatches ( core::array< s32 > & LODs ) const

pure virtual

Populates an array with the CurrentLOD of each patch.

Parameters

LODs	A reference to a core::array<s32> to hold the values

Returns: Number of elements in the array

◆ getIndexCount()

virtual u32 nirt::scene::ITerrainSceneNode::getIndexCount ( ) const

pure virtual

Get the number of indices currently in the meshbuffer.

Returns: The index count.

◆ getIndicesForPatch()

virtual s32 nirt::scene::ITerrainSceneNode::getIndicesForPatch	(	core::array< u32 > &	indices,
		s32	patchX,
		s32	patchZ,
		s32	LOD = `0`
	)

pure virtual

Gets the indices for a specified patch at a specified Level of Detail.

Parameters

indices	A reference to an array of u32 indices.
patchX	Patch x coordinate.
patchZ	Patch z coordinate.
LOD	The level of detail to get for that patch. If -1, then get the CurrentLOD. If the CurrentLOD is set to -1, meaning it's not shown, then it will retrieve the triangles at the highest LOD (0).

Returns: Number of indices put into the buffer.

◆ getMesh()

virtual IMesh * nirt::scene::ITerrainSceneNode::getMesh ( )

pure virtual

Get pointer to the mesh.

Returns: Pointer to the mesh.

◆ getMeshBufferForLOD()

virtual void nirt::scene::ITerrainSceneNode::getMeshBufferForLOD	(	IDynamicMeshBuffer &	mb,
		s32	LOD = `0`
	)		const

pure virtual

Gets the meshbuffer data based on a specified level of detail.

Parameters

mb	A reference to an IDynamicMeshBuffer object
LOD	The level of detail you want the indices from.

◆ loadHeightMap()

virtual bool nirt::scene::ITerrainSceneNode::loadHeightMap	(	io::IReadFile *	file,
		video::SColor	vertexColor = `video::SColor(255, 255, 255, 255)`,
		s32	smoothFactor = `0`
	)

pure virtual

Initializes the terrain data. Loads the vertices from the heightMapFile.

The file must contain a loadable image of the heightmap. The heightmap must be square.

Parameters

file	The file to read the image from. File is not rewinded.
vertexColor	Color of all vertices.
smoothFactor	Number of smoothing passes.

◆ loadHeightMapRAW()

virtual bool nirt::scene::ITerrainSceneNode::loadHeightMapRAW	(	io::IReadFile *	file,
		s32	bitsPerPixel = `16`,
		bool	signedData = `false`,
		bool	floatVals = `false`,
		s32	width = `0`,
		video::SColor	vertexColor = `video::SColor(255, 255, 255, 255)`,
		s32	smoothFactor = `0`
	)

pure virtual

Initializes the terrain data. Loads the vertices from the heightMapFile.

The data is interpreted as (signed) integers of the given bit size or floats (with 32bits, signed). Allowed bitsizes for integers are 8, 16, and 32. The heightmap must be square.

Parameters

file	The file to read the RAW data from. File is not rewinded.
bitsPerPixel	Size of data if integers used, for floats always use 32.
signedData	Whether we use signed or unsigned ints, ignored for floats.
floatVals	Whether the data is float or int.
width	Width (and also Height, as it must be square) of the heightmap. Use 0 for autocalculating from the filesize.
vertexColor	Color of all vertices.
smoothFactor	Number of smoothing passes.

◆ overrideLODDistance()

virtual bool nirt::scene::ITerrainSceneNode::overrideLODDistance	(	s32	LOD,
		f64	newDistance
	)

pure virtual

Override the default generation of distance thresholds.

For determining the LOD a patch is rendered at. If any LOD is overridden, then the scene node will no longer apply scaling factors to these values. If you override these distances, and then apply a scale to the scene node, it is your responsibility to update the new distances to work best with your new terrain size.

◆ scaleTexture()

virtual void nirt::scene::ITerrainSceneNode::scaleTexture	(	f32	scale = `1.0f`,
		f32	scale2 = `0.0f`
	)

pure virtual

Scales the base texture, similar to makePlanarTextureMapping.

Parameters

scale	The scaling amount. Values above 1.0 increase the number of time the texture is drawn on the terrain. Values below 0 will decrease the number of times the texture is drawn on the terrain. Using negative values will flip the texture, as well as still scaling it.
scale2	If set to 0 (default value), this will set the second texture coordinate set to the same values as in the first set. If this is another value than zero, it will scale the second texture coordinate set by this value.

◆ setCameraMovementDelta()

virtual void nirt::scene::ITerrainSceneNode::setCameraMovementDelta ( f32 delta )

pure virtual

Sets the movement camera threshold.

It is used to determine when to recalculate indices for the scene node. The default value is 10.0f.

◆ setCameraRotationDelta()

virtual void nirt::scene::ITerrainSceneNode::setCameraRotationDelta ( f32 delta )

pure virtual

Sets the rotation camera threshold.

It is used to determine when to recalculate indices for the scene node. The default value is 1.0f.

◆ setDynamicSelectorUpdate()

virtual void nirt::scene::ITerrainSceneNode::setDynamicSelectorUpdate ( bool bVal )

pure virtual

Sets whether or not the node should dynamically update its associated selector when the geomipmap data changes.

Parameters

bVal	Boolean value representing whether or not to update selector dynamically.

◆ setFixedBorderLOD()

virtual void nirt::scene::ITerrainSceneNode::setFixedBorderLOD ( nirt::s32 borderLOD = 0 )

pure virtual

Force node to use a fixed LOD level at the borders of the terrain.

This can be useful when several TerrainSceneNodes are connected.

Parameters

borderLOD When >= 0 all patches at the 4 borders will use the given LOD. When < 0 borders are just regular patches (that's default).

◆ setLODOfPatch()

virtual void nirt::scene::ITerrainSceneNode::setLODOfPatch	(	s32	patchX,
		s32	patchZ,
		s32	LOD = `0`
	)

pure virtual

Manually sets the LOD of a patch.

NOTE: Any values set here are overwritten again in the automatic recalculations when the camera changes.

Parameters

patchX	Patch x coordinate.
patchZ	Patch z coordinate.
LOD	The level of detail to set the patch to.

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

include/nirtcpp/core/engine/ITerrainSceneNode.hpp

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ getBoundingBox() [1/2]

◆ getBoundingBox() [2/2]

◆ getCurrentLODOfPatches()

◆ getIndexCount()

◆ getIndicesForPatch()

◆ getMesh()

◆ getMeshBufferForLOD()

◆ loadHeightMap()

◆ loadHeightMapRAW()

◆ overrideLODDistance()

◆ scaleTexture()

◆ setCameraMovementDelta()

◆ setCameraRotationDelta()

◆ setDynamicSelectorUpdate()

◆ setFixedBorderLOD()

◆ setLODOfPatch()