Collision Detection

Data Structures
struct	dContactGeom
	Describe the contact point between two geoms. More...
Functions
ODE_API void	dGeomDestroy (dGeomID geom)
	Destroy a geom, removing it from any space.
ODE_API void	dGeomSetData (dGeomID geom, void *data)
	Set the user-defined data pointer stored in the geom.
ODE_API void *	dGeomGetData (dGeomID geom)
	Get the user-defined data pointer stored in the geom.
ODE_API void	dGeomSetBody (dGeomID geom, dBodyID body)
	Set the body associated with a placeable geom.
ODE_API dBodyID	dGeomGetBody (dGeomID geom)
	Get the body associated with a placeable geom.
ODE_API void	dGeomSetPosition (dGeomID geom, dReal x, dReal y, dReal z)
	Set the position vector of a placeable geom.
ODE_API void	dGeomSetRotation (dGeomID geom, const dMatrix3 R)
	Set the rotation matrix of a placeable geom.
ODE_API void	dGeomSetQuaternion (dGeomID geom, const dQuaternion Q)
	Set the rotation of a placeable geom.
ODE_API const dReal *	dGeomGetPosition (dGeomID geom)
	Get the position vector of a placeable geom.
ODE_API const dReal *	dGeomGetRotation (dGeomID geom)
	Get the rotation matrix of a placeable geom.
ODE_API void	dGeomGetQuaternion (dGeomID geom, dQuaternion result)
	Get the rotation quaternion of a placeable geom.
ODE_API void	dGeomGetAABB (dGeomID geom, dReal aabb[6])
	Return the axis-aligned bounding box.
ODE_API int	dGeomIsSpace (dGeomID geom)
	Determing if a geom is a space.
ODE_API dSpaceID	dGeomGetSpace (dGeomID)
	Query for the space containing a particular geom.
ODE_API int	dGeomGetClass (dGeomID geom)
	Given a geom, this returns its class.
ODE_API void	dGeomSetCategoryBits (dGeomID geom, unsigned long bits)
	Set the "category" bitfield for the given geom.
ODE_API void	dGeomSetCollideBits (dGeomID geom, unsigned long bits)
	Set the "collide" bitfield for the given geom.
ODE_API unsigned long	dGeomGetCategoryBits (dGeomID)
	Get the "category" bitfield for the given geom.
ODE_API unsigned long	dGeomGetCollideBits (dGeomID)
	Get the "collide" bitfield for the given geom.
ODE_API void	dGeomEnable (dGeomID geom)
	Enable a geom.
ODE_API void	dGeomDisable (dGeomID geom)
	Disable a geom.
ODE_API int	dGeomIsEnabled (dGeomID geom)
	Check to see if a geom is enabled.

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Detailed Description

ODE has two main components: a dynamics simulation engine and a collision detection engine. The collision engine is given information about the shape of each body. At each time step it figures out which bodies touch each other and passes the resulting contact point information to the user. The user in turn creates contact joints between bodies.

Using ODE's collision detection is optional - an alternative collision detection system can be used as long as it can supply the right kinds of contact information.

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Function Documentation

ODE_API void dGeomDestroy (  dGeomID  geom  )

Destroy a geom, removing it from any space. Destroy a geom, removing it from any space it is in first. This one function destroys a geom of any type, but to create a geom you must call a creation function for that type. When a space is destroyed, if its cleanup mode is 1 (the default) then all the geoms in that space are automatically destroyed as well. Parameters: geom  the geom to be destroyed.

ODE_API void dGeomDisable (  dGeomID  geom  )

Disable a geom. Disabled geoms are completely ignored by dSpaceCollide and dSpaceCollide2, although they can still be members of a space. New geoms are created in the enabled state. Parameters: geom  the geom to disable See also: dGeomDisable dGeomIsEnabled

ODE_API void dGeomEnable (  dGeomID  geom  )

Enable a geom. Disabled geoms are completely ignored by dSpaceCollide and dSpaceCollide2, although they can still be members of a space. New geoms are created in the enabled state. Parameters: geom  the geom to enable See also: dGeomDisable dGeomIsEnabled

ODE_API void dGeomGetAABB (  dGeomID  geom, dReal  aabb[6] )

Return the axis-aligned bounding box. Return in aabb an axis aligned bounding box that surrounds the given geom. The aabb array has elements (minx, maxx, miny, maxy, minz, maxz). If the geom is a space, a bounding box that surrounds all contained geoms is returned. This function may return a pre-computed cached bounding box, if it can determine that the geom has not moved since the last time the bounding box was computed. Parameters: geom  the geom to query aabb  the returned bounding box

ODE_API dBodyID dGeomGetBody (  dGeomID  geom  )

Get the body associated with a placeable geom. Parameters: geom  the geom to query. See also: dGeomSetBody

ODE_API unsigned long dGeomGetCategoryBits (  dGeomID   )

Get the "category" bitfield for the given geom. Parameters: geom  the geom to set bits  the new bitfield value See also: dGeomSetCategoryBits

ODE_API int dGeomGetClass (  dGeomID  geom  )

Given a geom, this returns its class. The ODE classes are: dSphereClass dBoxClass dCylinderClass dPlaneClass dRayClass dConvexClass dGeomTransformClass dTriMeshClass dSimpleSpaceClass dHashSpaceClass dQuadTreeSpaceClass dFirstUserClass dLastUserClass User-defined class will return their own number. Parameters: geom  the geom to query Returns: The geom class ID.

ODE_API unsigned long dGeomGetCollideBits (  dGeomID   )

Get the "collide" bitfield for the given geom. Parameters: geom  the geom to set bits  the new bitfield value See also: dGeomSetCollideBits

ODE_API void* dGeomGetData (  dGeomID  geom  )

Get the user-defined data pointer stored in the geom. Parameters: geom  the geom containing the data

ODE_API const dReal* dGeomGetPosition (  dGeomID  geom  )

Get the position vector of a placeable geom. If the geom is attached to a body, the body's position will be returned. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to query. Returns: A pointer to the geom's position vector. Remarks: The returned value is a pointer to the geom's internal data structure. It is valid until any changes are made to the geom. See also: dBodyGetPosition

ODE_API void dGeomGetQuaternion (  dGeomID  geom, dQuaternion  result )

Get the rotation quaternion of a placeable geom. If the geom is attached to a body, the body's quaternion will be returned. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to query. result  a copy of the rotation quaternion. See also: dBodyGetQuaternion

ODE_API const dReal* dGeomGetRotation (  dGeomID  geom  )

Get the rotation matrix of a placeable geom. If the geom is attached to a body, the body's rotation will be returned. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to query. Returns: A pointer to the geom's rotation matrix. Remarks: The returned value is a pointer to the geom's internal data structure. It is valid until any changes are made to the geom. See also: dBodyGetRotation

ODE_API dSpaceID dGeomGetSpace (  dGeomID   )

Query for the space containing a particular geom. Parameters: geom  the geom to query Returns: The space that contains the geom, or NULL if the geom is not contained by a space.

ODE_API int dGeomIsEnabled (  dGeomID  geom  )

Check to see if a geom is enabled. Disabled geoms are completely ignored by dSpaceCollide and dSpaceCollide2, although they can still be members of a space. New geoms are created in the enabled state. Parameters: geom  the geom to query Returns: Non-zero if the geom is enabled, zero otherwise. See also: dGeomDisable dGeomIsEnabled

ODE_API int dGeomIsSpace (  dGeomID  geom  )

Determing if a geom is a space. Parameters: geom  the geom to query Returns: Non-zero if the geom is a space, zero otherwise.

ODE_API void dGeomSetBody (  dGeomID  geom, dBodyID  body )

Set the body associated with a placeable geom. Setting a body on a geom automatically combines the position vector and rotation matrix of the body and geom, so that setting the position or orientation of one will set the value for both objects. Setting a body ID of zero gives the geom its own position and rotation, independent from any body. If the geom was previously connected to a body then its new independent position/rotation is set to the current position/rotation of the body. Calling these functions on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to connect body  the body to attach to the geom

ODE_API void dGeomSetCategoryBits (  dGeomID  geom, unsigned long  bits )

Set the "category" bitfield for the given geom. The category bitfield is used by spaces to govern which geoms will interact with each other. The bitfield is guaranteed to be at least 32 bits wide. The default category values for newly created geoms have all bits set. Parameters: geom  the geom to set bits  the new bitfield value

ODE_API void dGeomSetCollideBits (  dGeomID  geom, unsigned long  bits )

Set the "collide" bitfield for the given geom. The collide bitfield is used by spaces to govern which geoms will interact with each other. The bitfield is guaranteed to be at least 32 bits wide. The default category values for newly created geoms have all bits set. Parameters: geom  the geom to set bits  the new bitfield value

ODE_API void dGeomSetData (  dGeomID  geom, void *  data )

Set the user-defined data pointer stored in the geom. Parameters: geom  the geom to hold the data data  the data pointer to be stored

ODE_API void dGeomSetPosition (  dGeomID  geom, dReal  x, dReal  y, dReal  z )

Set the position vector of a placeable geom. If the geom is attached to a body, the body's position will also be changed. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to set. x  the new X coordinate. y  the new Y coordinate. z  the new Z coordinate. See also: dBodySetPosition

ODE_API void dGeomSetQuaternion (  dGeomID  geom, const dQuaternion  Q )

Set the rotation of a placeable geom. If the geom is attached to a body, the body's rotation will also be changed. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to set. Q  the new rotation. See also: dBodySetQuaternion

ODE_API void dGeomSetRotation (  dGeomID  geom, const dMatrix3  R )

Set the rotation matrix of a placeable geom. If the geom is attached to a body, the body's rotation will also be changed. Calling this function on a non-placeable geom results in a runtime error in the debug build of ODE. Parameters: geom  the geom to set. R  the new rotation matrix. See also: dBodySetRotation

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