nirt::scene::ISceneCollisionManager Class Reference

The Scene Collision Manager provides methods for performing collision tests and picking on scene nodes. More...

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

Inheritance diagram for nirt::scene::ISceneCollisionManager:

Collaboration diagram for nirt::scene::ISceneCollisionManager:

Public Member Functions
virtual bool	getCollisionPoint (SCollisionHit &hitResult, const core::line3d< f32 > &ray, ITriangleSelector *selector)=0
	Finds the nearest collision point of a line and lots of triangles, if there is one.
virtual bool	getCollisionPoint (const core::line3d< f32 > &ray, ITriangleSelector *selector, core::vector3df &outCollisionPoint, core::triangle3df &outTriangle, ISceneNode *&outNode)
	Finds the nearest collision point of a line and lots of triangles, if there is one.
virtual core::vector3df	getCollisionResultPosition (ITriangleSelector *selector, const core::vector3df &ellipsoidPosition, const core::vector3df &ellipsoidRadius, const core::vector3df &ellipsoidDirectionAndSpeed, core::triangle3df &triout, core::vector3df &hitPosition, bool &outFalling, ISceneNode *&outNode, f32 slidingSpeed=0.0005f, const core::vector3df &gravityDirectionAndSpeed=core::vector3df(0.0f, 0.0f, 0.0f))=0
	Collides a moving ellipsoid with a 3d world with gravity and returns the resulting new position of the ellipsoid.
virtual core::line3d< f32 >	getRayFromScreenCoordinates (const core::position2d< s32 > &pos, const ICameraSceneNode *camera=0)=0
	Returns a 3d ray which would go through the 2d screen coordinates.
virtual core::position2d< s32 >	getScreenCoordinatesFrom3DPosition (const core::vector3df &pos, const ICameraSceneNode *camera=0, bool useViewPort=false)=0
	Calculates 2d screen position from a 3d position.
virtual ISceneNode *	getSceneNodeFromScreenCoordinatesBB (const core::position2d< s32 > &pos, s32 idBitMask=0, bool bNoDebugObjects=false, ISceneNode *root=0)=0
	Gets the scene node, which is currently visible under the given screen coordinates, viewed from the currently active camera.
virtual ISceneNode *	getSceneNodeFromRayBB (const core::line3d< f32 > &ray, s32 idBitMask=0, bool bNoDebugObjects=false, ISceneNode *root=0)=0
	Returns the nearest scene node which collides with a 3d ray and whose id matches a bitmask.
virtual ISceneNode *	getSceneNodeFromCameraBB (const ICameraSceneNode *camera, s32 idBitMask=0, bool bNoDebugObjects=false)=0
	Get the scene node, which the given camera is looking at and whose id matches the bitmask.
virtual ISceneNode *	getSceneNodeAndCollisionPointFromRay (SCollisionHit &hitResult, const core::line3df &ray, s32 idBitMask=0, ISceneNode *collisionRootNode=0, bool noDebugObjects=false)=0
	Perform a ray/box and ray/triangle collision check on a hierarchy of scene nodes.
virtual ISceneNode *	getSceneNodeAndCollisionPointFromRay (const core::line3df &ray, core::vector3df &outCollisionPoint, core::triangle3df &outTriangle, s32 idBitMask=0, ISceneNode *collisionRootNode=0, bool noDebugObjects=false)
	Perform a ray/box and ray/triangle collision check on a hierarchy of scene nodes.
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::IReferenceCounted
void	setDebugName (const c8 *newName)
	Sets the debug name of the object.

Detailed Description

The Scene Collision Manager provides methods for performing collision tests and picking on scene nodes.

Member Function Documentation

getCollisionPoint() [1/2]

virtual bool nirt::scene::ISceneCollisionManager::getCollisionPoint ( const core::line3d< f32 > &  ray, ITriangleSelector *  selector, core::vector3df &  outCollisionPoint, core::triangle3df &  outTriangle, ISceneNode *&  outNode  )

inlinevirtual

Finds the nearest collision point of a line and lots of triangles, if there is one.

Parameters

ray	Line with which collisions are tested.
selector	TriangleSelector containing the triangles. It can be created for example using ISceneManager::createTriangleSelector() or ISceneManager::createTriangleOctreeSelector().
outCollisionPoint	If a collision is detected, this will contain the position of the nearest collision to the line-start.
outTriangle	If a collision is detected, this will contain the triangle with which the ray collided.
outNode	If a collision is detected, this will contain the scene node associated with the triangle that was hit.

Returns

True if a collision was detected and false if not.

getCollisionPoint() [2/2]

virtual bool nirt::scene::ISceneCollisionManager::getCollisionPoint ( SCollisionHit &  hitResult, const core::line3d< f32 > &  ray, ITriangleSelector *  selector  )

pure virtual

Finds the nearest collision point of a line and lots of triangles, if there is one.

Parameters

hitResult	Contains collision result when there was a collision detected.
ray	Line with which collisions are tested.
selector	TriangleSelector to be used for the collision check.

Returns

true if a collision was detected and false if not.

getCollisionResultPosition()

virtual core::vector3df nirt::scene::ISceneCollisionManager::getCollisionResultPosition ( ITriangleSelector *  selector, const core::vector3df &  ellipsoidPosition, const core::vector3df &  ellipsoidRadius, const core::vector3df &  ellipsoidDirectionAndSpeed, core::triangle3df &  triout, core::vector3df &  hitPosition, bool &  outFalling, ISceneNode *&  outNode, f32  slidingSpeed = 0.0005f, const core::vector3df &  gravityDirectionAndSpeed = core::vector3df(0.0f, 0.0f, 0.0f)  )

pure virtual

Collides a moving ellipsoid with a 3d world with gravity and returns the resulting new position of the ellipsoid.

This can be used for moving a character in a 3d world: The character will slide at walls and is able to walk up stairs. The method used how to calculate the collision result position is based on the paper "Improved Collision detection and Response" by Kasper Fauerby.

Parameters

selector	TriangleSelector containing the triangles of the world. It can be created for example using ISceneManager::createTriangleSelector() or ISceneManager::createTriangleOctreeSelector().
ellipsoidPosition	Position of the ellipsoid.
ellipsoidRadius	Radius of the ellipsoid.
ellipsoidDirectionAndSpeed	Direction and speed of the movement of the ellipsoid.
triout	Optional parameter where the last triangle causing a collision is stored, if there is a collision.
hitPosition	Return value for the position of the collision
outFalling	Is set to true if the ellipsoid is falling down, caused by gravity.
outNode	the node with which the ellipsoid collided (if any)
slidingSpeed	DOCUMENTATION NEEDED.
gravityDirectionAndSpeed	Direction and force of gravity.

Returns

New position of the ellipsoid.

getRayFromScreenCoordinates()

virtual core::line3d< f32 > nirt::scene::ISceneCollisionManager::getRayFromScreenCoordinates ( const core::position2d< s32 > &  pos, const ICameraSceneNode *  camera = 0  )

pure virtual

Returns a 3d ray which would go through the 2d screen coordinates.

Parameters

pos	Screen coordinates in pixels.
camera	Camera from which the ray starts. If null, the active camera is used.

Returns

Ray starting from the position of the camera and ending at a length of the far value of the camera at a position which would be behind the 2d screen coordinates.

getSceneNodeAndCollisionPointFromRay() [1/2]

virtual ISceneNode * nirt::scene::ISceneCollisionManager::getSceneNodeAndCollisionPointFromRay ( const core::line3df &  ray, core::vector3df &  outCollisionPoint, core::triangle3df &  outTriangle, s32  idBitMask = 0, ISceneNode *  collisionRootNode = 0, bool  noDebugObjects = false  )

inlinevirtual

Perform a ray/box and ray/triangle collision check on a hierarchy of scene nodes.

Works same as other getSceneNodeAndCollisionPointFromRay but returns less information. (was written before the other getSceneNodeAndCollisionPointFromRay implementation).

Parameters

ray	Line with which collisions are tested.
outCollisionPoint	If a collision is detected, this will contain the position of the nearest collision.
outTriangle	If a collision is detected, this will contain the triangle with which the ray collided.
idBitMask	Only scene nodes with an id which matches at least one of the bits contained in this mask will be tested. However, if this parameter is 0, then all nodes are checked.
collisionRootNode	the scene node at which to begin checking. Only this node and its children will be checked. If you want to check the entire scene, pass 0, and the root scene node will be used (this is the default).
noDebugObjects	when true, debug objects are not considered viable targets. Debug objects are scene nodes with IsDebugObject() = true.

Returns

Returns the scene node containing the hit triangle nearest to ray.start. If no collision is detected, then 0 is returned.

getSceneNodeAndCollisionPointFromRay() [2/2]

virtual ISceneNode * nirt::scene::ISceneCollisionManager::getSceneNodeAndCollisionPointFromRay ( SCollisionHit &  hitResult, const core::line3df &  ray, s32  idBitMask = 0, ISceneNode *  collisionRootNode = 0, bool  noDebugObjects = false  )

pure virtual

Perform a ray/box and ray/triangle collision check on a hierarchy of scene nodes.

This checks all scene nodes under the specified one, first by ray/bounding box, and then by accurate ray/triangle collision, finding the nearest collision, and the scene node containing it. It returns the node hit, and (via output parameters) the position of the collision, and the triangle that was hit.

All scene nodes in the hierarchy tree under the specified node are checked. Only nodes that are visible, with an ID that matches at least one bit in the supplied bitmask, and which have a triangle selector are considered as candidates for being hit. You do not have to build a meta triangle selector; the individual triangle selectors of each candidate scene node are used automatically.

Parameters

ray	Line with which collisions are tested.
outCollisionPoint	If a collision is detected, this will contain the position of the nearest collision.
outTriangle	If a collision is detected, this will contain the triangle with which the ray collided.
idBitMask	Only scene nodes with an id which matches at least one of the bits contained in this mask will be tested. However, if this parameter is 0, then all nodes are checked.
collisionRootNode	the scene node at which to begin checking. Only this node and its children will be checked. If you want to check the entire scene, pass 0, and the root scene node will be used (this is the default).
noDebugObjects	when true, debug objects are not considered viable targets. Debug objects are scene nodes with IsDebugObject() = true.

Returns

Returns the scene node containing the hit triangle nearest to ray.start. If no collision is detected, then 0 is returned.

getSceneNodeFromCameraBB()

virtual ISceneNode * nirt::scene::ISceneCollisionManager::getSceneNodeFromCameraBB ( const ICameraSceneNode *  camera, s32  idBitMask = 0, bool  bNoDebugObjects = false  )

pure virtual

Get the scene node, which the given camera is looking at and whose id matches the bitmask.

A ray is simply cast from the position of the camera to the view target position, and all scene nodes are tested against this ray. The collision tests are done using a bounding box for each scene node.

Parameters

camera	Camera from which the ray is cast.
idBitMask	Only scene nodes with an id which matches at least one of the bits contained in this mask will be tested. However, if this parameter is 0, then all nodes are checked. feature is disabled. Please note that the default node id of -1 will match with every bitmask != 0
bNoDebugObjects	Doesn't take debug objects into account when true. These are scene nodes with IsDebugObject() = true.

Returns

Scene node nearest to the camera, which collides with the ray and matches the idBitMask, if the mask is not null. If no scene node is found, 0 is returned.

getSceneNodeFromRayBB()

virtual ISceneNode * nirt::scene::ISceneCollisionManager::getSceneNodeFromRayBB ( const core::line3d< f32 > &  ray, s32  idBitMask = 0, bool  bNoDebugObjects = false, ISceneNode *  root = 0  )

pure virtual

Returns the nearest scene node which collides with a 3d ray and whose id matches a bitmask.

The collision tests are done using a bounding box for each scene node. The recursive search can be limited be specifying a scene node.

Parameters

ray	Line with which collisions are tested.
idBitMask	Only scene nodes with an id which matches at least one of the bits contained in this mask will be tested. However, if this parameter is 0, then all nodes are checked.
bNoDebugObjects	Doesn't take debug objects into account when true. These are scene nodes with IsDebugObject() = true.
root	If different from 0, the search is limited to the children of this node.

Returns

Scene node nearest to ray.start, which collides with the ray and matches the idBitMask, if the mask is not null. If no scene node is found, 0 is returned.

getSceneNodeFromScreenCoordinatesBB()

virtual ISceneNode * nirt::scene::ISceneCollisionManager::getSceneNodeFromScreenCoordinatesBB ( const core::position2d< s32 > &  pos, s32  idBitMask = 0, bool  bNoDebugObjects = false, ISceneNode *  root = 0  )

pure virtual

Gets the scene node, which is currently visible under the given screen coordinates, viewed from the currently active camera.

The collision tests are done using a bounding box for each scene node. You can limit the recursive search so just all children of the specified root are tested.

Parameters

pos	Position in pixel screen coordinates, under which the returned scene node will be.
idBitMask	Only scene nodes with an id with bits set like in this mask will be tested. If the BitMask is 0, this feature is disabled. Please note that the default node id of -1 will match with every bitmask != 0
bNoDebugObjects	Doesn't take debug objects into account when true. These are scene nodes with IsDebugObject() = true.
root	If different from 0, the search is limited to the children of this node.

Returns

Visible scene node under screen coordinates with matching bits in its id. If there is no scene node under this position, 0 is returned.

getScreenCoordinatesFrom3DPosition()

virtual core::position2d< s32 > nirt::scene::ISceneCollisionManager::getScreenCoordinatesFrom3DPosition ( const core::vector3df &  pos, const ICameraSceneNode *  camera = 0, bool  useViewPort = false  )

pure virtual

Calculates 2d screen position from a 3d position.

Parameters

pos	3D position in world space to be transformed into 2d.
camera	Camera to be used. If null, the currently active camera is used.
useViewPort	Calculate screen coordinates relative to the current view port. Please note that unless the driver does not take care of the view port, it is usually best to get the result in absolute screen coordinates (flag=false).

Returns

2d screen coordinates which a object in the 3d world would have if it would be rendered to the screen. If the 3d position is behind the camera, it is set to (-1000,-1000). In most cases you can ignore this fact, because if you use this method for drawing a decorator over a 3d object, it will be clipped by the screen borders.

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

• include/nirtcpp/core/engine/ISceneCollisionManager.hpp