# -*- indent-tabs-mode: t -*- # Forward declarations cdef class Joint # Body cdef class _Body(_soya._World): """The rigid body class encapsulating the ODE body. This class represents a rigid body that has a location and orientation in space and that stores the mass properties of an object. When creating a Body object you have to pass the world it belongs to as argument to the constructor:: >>> import ode >>> w = ode.World() >>> b = ode.Body(w) """ cdef dBodyID _bid #cdef _World _world #cdef dReal *_R # Rotation matrix of the ODE body #cdef dReal *_P # Position array of the ODE body cdef GLfloat _q[4] # Previous quaternion cdef GLfloat _p[4] # Previous position cdef float _t # Cumulative round time cdef int _valid # Is the previous quaternion/position valid? cdef readonly joints def __new__(self, _World world=None, *args, **kw): #self._world = world if world is None: self._bid = NULL #self._R = NULL #self._P = NULL else: self._bid = dBodyCreate(world._wid) #world._add_body(self) #self._R = dBodyGetRotation(self._bid) #self._P = dBodyGetPosition(self._bid) self._valid = 0 def __init__(self, _World world=None, *args, **kw): self.joints = [] _soya._World.__init__(self, world, *args, **kw) def __dealloc__(self): print '__dealloc__ ode._Body' if self._bid!=NULL: dBodyDestroy(self._bid) cdef void _add_joint(self, Joint joint): self.joints.append(joint) cdef void _remove_joint(self, Joint joint): self.joints.remove(joint) def begin_round(self): """Save the previous quaternion and position for interpolation. We can do this in begin_round because the simulation calls begin_round before stepping.""" cdef dReal *q q = dBodyGetQuaternion(self._bid) self._q[0] = q[1] self._q[1] = q[2] self._q[2] = q[3] self._q[3] = q[0] q = dBodyGetPosition(self._bid) self._p[0] = q[0] self._p[1] = q[1] self._p[2] = q[2] self._valid = 1 # Mark the saved stuff as valid self._t = 0.0 # Reset the round time accumulator # cdef void _update_matrix(self): # """Copy attributes from the body back to _matrix""" # # cdef GLfloat *m # # # Only copy if the body is enabled # if dBodyIsEnabled(self._bid): # m = self._matrix # m[12] = self._P[0] # m[13] = self._P[1] # m[14] = self._P[2] # m[16] = 1.0 # m[17] = 1.0 # m[18] = 1.0 # # m[0] = self._R[0] # m[1] = self._R[4] # m[2] = self._R[8] # m[4] = self._R[1] # m[5] = self._R[5] # m[6] = self._R[9] # m[8] = self._R[2] # m[9] = self._R[6] # m[10] = self._R[10] # # # Don't need to do this now because we require that bodies # # be direct children of the Simulation # #_soya.multiply_matrix(r, self.world._root_matrix(), m) # #_soya.multiply_matrix(self._matrix, self._parent._inverted_root_matrix(), r) # # We call _soya._World._invalidate instead of self._invalidate # # because self._invalidate has been overridden to to update # # the ODE rotation and position when the Body is moved manually. # _soya._World._invalidate(self) cdef void _invalidate(self): """Update the body's matrix after invalidating the root and inverted root matrices. We do this here because all movement methods must call this.""" cdef dMatrix3 R cdef GLfloat *m _soya._World._invalidate(self) # Don't need to do this any more because we know we are a direct # child of the Simulation. #_soya.multiply_matrix(m, self._root_matrix(), self.world._inverted_root_matrix()) m = self._matrix R[0] = m[0] R[1] = m[4] R[2] = m[8] R[3] = 0.0 R[4] = m[1] R[5] = m[5] R[6] = m[9] R[7] = 0.0 R[8] = m[2] R[9] = m[6] R[10] = m[10] R[11] = 0.0 # XXX Overriding the movement methods would be faster due to the fact # that we wouldn't have to copy the rotation matrix as well dBodySetPosition(self._bid, m[12], m[13], m[14]) dBodySetRotation(self._bid, R) # Mark the previous position and quaternion as invalid self._valid = 0 def advance_time(self, float proportion): """Interpolate between the last two quaternions""" cdef GLfloat q[4] cdef dReal *r, *p cdef float t self._t = self._t + proportion if dBodyIsEnabled(self._bid): r = dBodyGetQuaternion(self._bid) p = dBodyGetPosition(self._bid) if self._valid: t = 1.0 - self._t # Linearly interpolate between the current quaternion and the last # one q[0] = t * self._q[0] + self._t * r[1] q[1] = t * self._q[1] + self._t * r[2] q[2] = t * self._q[2] + self._t * r[3] q[3] = t * self._q[3] + self._t * r[0] # Convert the quaternion to a matrix (also normalizes) _soya.matrix_from_quaternion(self._matrix, q) # Interpolate the position, too self._matrix[12] = t * self._p[0] + self._t * p[0] self._matrix[13] = t * self._p[1] + self._t * p[1] self._matrix[14] = t * self._p[2] + self._t * p[2] else: # Use the current quaternion and position q[0] = r[1] q[1] = r[2] q[2] = r[3] q[3] = r[0] _soya.matrix_from_quaternion(self._matrix, q) self._matrix[12] = p[0] self._matrix[13] = p[1] self._matrix[14] = p[2] # Call _soya._World's _invalidate since we override _invalidate # to detect when the position is updated externally _soya._World._invalidate(self) # Make sure advance_time is called on all our children _soya._World.advance_time(self, proportion) property linear_velocity: def __set__(self, vel): dBodySetLinearVel(self._bid, vel[0], vel[1], vel[2]) def __get__(self): cdef dReal* p p = dBodyGetLinearVel(self._bid) return (p[0], p[1], p[2]) property angular_velocity: def __set__(self, vel): """setAngularVel(vel) Set the angular velocity of the body. @param vel: New angular velocity @type vel: 3-sequence of floats """ dBodySetAngularVel(self._bid, vel[0], vel[1], vel[2]) def __get__(self): """getAngularVel() -> 3-tuple Get the current angular velocity of the body. """ cdef dReal* p # The "const" in the original return value is cast away p = dBodyGetAngularVel(self._bid) return (p[0],p[1],p[2]) property mass: def __set__(self, Mass mass): """setMass(mass) Set the mass properties of the body. The argument mass must be an instance of a Mass object. @param mass: Mass properties @type mass: Mass """ dBodySetMass(self._bid, &mass._mass) def __get__(self): """getMass() -> mass Return the mass properties as a Mass object. """ cdef Mass m m=Mass() dBodyGetMass(self._bid, &m._mass) return m # addForce def addForce(self, f): """addForce(f) Add an external force f given in absolute coordinates. The force is applied at the center of mass. @param f: Force @type f: 3-sequence of floats """ dBodyAddForce(self._bid, f[0], f[1], f[2]) # addTorque def addTorque(self, t): """addTorque(t) Add an external torque t given in absolute coordinates. @param t: Torque @type t: 3-sequence of floats """ dBodyAddTorque(self._bid, t[0], t[1], t[2]) # addRelForce def addRelForce(self, f): """addRelForce(f) Add an external force f given in relative coordinates (relative to the body's own frame of reference). The force is applied at the center of mass. @param f: Force @type f: 3-sequence of floats """ dBodyAddRelForce(self._bid, f[0], f[1], f[2]) # addRelTorque def addRelTorque(self, t): """addRelTorque(t) Add an external torque t given in relative coordinates (relative to the body's own frame of reference). @param t: Torque @type t: 3-sequence of floats """ dBodyAddRelTorque(self._bid, t[0], t[1], t[2]) # addForceAtPos def addForceAtPos(self, f, p): """addForceAtPos(f, p) Add an external force f at position p. Both arguments must be given in absolute coordinates. @param f: Force @param p: Position @type f: 3-sequence of floats @type p: 3-sequence of floats """ dBodyAddForceAtPos(self._bid, f[0], f[1], f[2], p[0], p[1], p[2]) # addForceAtRelPos def addForceAtRelPos(self, f, p): """addForceAtRelPos(f, p) Add an external force f at position p. f is given in absolute coordinates and p in absolute coordinates. @param f: Force @param p: Position @type f: 3-sequence of floats @type p: 3-sequence of floats """ dBodyAddForceAtRelPos(self._bid, f[0], f[1], f[2], p[0], p[1], p[2]) # addRelForceAtPos def addRelForceAtPos(self, f, p): """addRelForceAtPos(f, p) Add an external force f at position p. f is given in relative coordinates and p in relative coordinates. @param f: Force @param p: Position @type f: 3-sequence of floats @type p: 3-sequence of floats """ dBodyAddRelForceAtPos(self._bid, f[0], f[1], f[2], p[0], p[1], p[2]) # addRelForceAtRelPos def addRelForceAtRelPos(self, f, p): """addRelForceAtRelPos(f, p) Add an external force f at position p. Both arguments must be given in relative coordinates. @param f: Force @param p: Position @type f: 3-sequence of floats @type p: 3-sequence of floats """ dBodyAddRelForceAtRelPos(self._bid, f[0], f[1], f[2], p[0], p[1], p[2]) # getForce def getForce(self): """getForce() -> 3-tuple Return the current accumulated force. """ cdef dReal* f # The "const" in the original return value is cast away f = dBodyGetForce(self._bid) return (f[0],f[1],f[2]) # getTorque def getTorque(self): """getTorque() -> 3-tuple Return the current accumulated torque. """ cdef dReal* f # The "const" in the original return value is cast away f = dBodyGetTorque(self._bid) return (f[0],f[1],f[2]) # setForce def setForce(self, f): """setForce(f) Set the body force accumulation vector. @param f: Force @type f: 3-tuple of floats """ dBodySetForce(self._bid, f[0], f[1], f[2]) # setTorque def setTorque(self, t): """setTorque(t) Set the body torque accumulation vector. @param t: Torque @type t: 3-tuple of floats """ dBodySetTorque(self._bid, t[0], t[1], t[2]) # getRelPointPos def getRelPointPos(self, p): """getRelPointPos(p) -> 3-tuple Utility function that takes a point p on a body and returns that point's position in global coordinates. The point p must be given in body relative coordinates. @param p: Body point (local coordinates) @type p: 3-sequence of floats """ cdef dVector3 res dBodyGetRelPointPos(self._bid, p[0], p[1], p[2], res) return (res[0], res[1], res[2]) # getRelPointVel def getRelPointVel(self, p): """getRelPointVel(p) -> 3-tuple Utility function that takes a point p on a body and returns that point's velocity in global coordinates. The point p must be given in body relative coordinates. @param p: Body point (local coordinates) @type p: 3-sequence of floats """ cdef dVector3 res dBodyGetRelPointVel(self._bid, p[0], p[1], p[2], res) return (res[0], res[1], res[2]) # getPointVel def getPointVel(self, p): """getPointVel(p) -> 3-tuple Utility function that takes a point p on a body and returns that point's velocity in global coordinates. The point p must be given in global coordinates. @param p: Body point (global coordinates) @type p: 3-sequence of floats """ cdef dVector3 res dBodyGetPointVel(self._bid, p[0], p[1], p[2], res) return (res[0], res[1], res[2]) # getPosRelPoint def getPosRelPoint(self, p): """getPosRelPoint(p) -> 3-tuple This is the inverse of getRelPointPos(). It takes a point p in global coordinates and returns the point's position in body-relative coordinates. @param p: Body point (global coordinates) @type p: 3-sequence of floats """ cdef dVector3 res dBodyGetPosRelPoint(self._bid, p[0], p[1], p[2], res) return (res[0], res[1], res[2]) # vectorToWorld def vectorToWorld(self, v): """vectorToWorld(v) -> 3-tuple Given a vector v expressed in the body coordinate system, rotate it to the world coordinate system. @param v: Vector in body coordinate system @type v: 3-sequence of floats """ cdef dVector3 res dBodyVectorToWorld(self._bid, v[0], v[1], v[2], res) return (res[0], res[1], res[2]) # vectorFromWorld def vectorFromWorld(self, v): """vectorFromWorld(v) -> 3-tuple Given a vector v expressed in the world coordinate system, rotate it to the body coordinate system. @param v: Vector in world coordinate system @type v: 3-sequence of floats """ cdef dVector3 res dBodyVectorFromWorld(self._bid, v[0], v[1], v[2], res) return (res[0], res[1], res[2]) property enabled: def __set__(self, flag): """enable() Manually enable a body. """ if flag: dBodyEnable(self._bid) else: dBodyDisable(self._bid) def __get__(self): """isEnabled() -> bool Check if a body is currently enabled. """ return dBodyIsEnabled(self._bid) property finite_rotation_mode: def __set__(self, mode): """setFiniteRotationMode(mode) This function controls the way a body's orientation is updated at each time step. The mode argument can be: - 0: An "infinitesimal" orientation update is used. This is fast to compute, but it can occasionally cause inaccuracies for bodies that are rotating at high speed, especially when those bodies are joined to other bodies. This is the default for every new body that is created. - 1: A "finite" orientation update is used. This is more costly to compute, but will be more accurate for high speed rotations. Note however that high speed rotations can result in many types of error in a world, and this mode will only fix one of those sources of error. @param mode: Rotation mode (0/1) @type mode: int """ dBodySetFiniteRotationMode(self._bid, mode) def __get__(self): """getFiniteRotationMode() -> mode (0/1) Return the current finite rotation mode of a body (0 or 1). See setFiniteRotationMode(). """ return dBodyGetFiniteRotationMode(self._bid) property finite_rotation_axis: def __set__(self, a): """setFiniteRotationAxis(a) Set the finite rotation axis of the body. This axis only has a meaning when the finite rotation mode is set (see setFiniteRotationMode()). @param a: Axis @type a: 3-sequence of floats """ dBodySetFiniteRotationAxis(self._bid, a[0], a[1], a[2]) def __get__(self): """getFiniteRotationAxis() -> 3-tuple Return the current finite rotation axis of the body. """ cdef dVector3 p # The "const" in the original return value is cast away dBodyGetFiniteRotationAxis(self._bid, p) return (p[0],p[1],p[2]) property num_joints: def __get__(self): """getNumJoints() -> int Return the number of joints that are attached to this body. """ return dBodyGetNumJoints(self._bid) property gravity_mode: def __set__(self, mode): """setGravityMode(mode) Set whether the body is influenced by the world's gravity or not. If mode is True it is, otherwise it isn't. Newly created bodies are always influenced by the world's gravity. @param mode: Gravity mode @type mode: bool """ dBodySetGravityMode(self._bid, mode) def __get__(self): """getGravityMode() -> bool Return True if the body is influenced by the world's gravity. """ return dBodyGetGravityMode(self._bid)