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expose pybullet changeDynamics(spinningFriction=..., rollingFriction=..., restitution=...)

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Bullet C-API b3ChangeDynamicsInfoSetSpinningFriction/RollingFriction/Resitution
b3PhysicsParamSetRestitutionVelocityThreshold, / pybullet.setPhysicsEngineParameter restitutionVelocityThreshold:
if the velocity is below this threshhold, the restitution is zero (this prevents energy buildup at near-resting state)
pybullet restitution.py example.
This commit is contained in:
Erwin Coumans
2017-05-26 18:14:38 -07:00
parent 8c6d4a4c85
commit b645963879
12 changed files with 317 additions and 51 deletions
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48
examples/SharedMemory/PhysicsClientC_API.cpp
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@@ -392,6 +392,18 @@ int b3PhysicsParamSetEnableFileCaching(b3SharedMemoryCommandHandle commandHandle
}
int b3PhysicsParamSetRestitutionVelocityThreshold(b3SharedMemoryCommandHandle commandHandle, double restitutionVelocityThreshold)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command->m_type == CMD_SEND_PHYSICS_SIMULATION_PARAMETERS);
command->m_physSimParamArgs.m_restitutionVelocityThreshold = restitutionVelocityThreshold;
command->m_updateFlags |= SIM_PARAM_UPDATE_RESTITUTION_VELOCITY_THRESHOLD ;
return 0;
}
int b3PhysicsParamSetNumSolverIterations(b3SharedMemoryCommandHandle commandHandle, int numSolverIterations)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
@@ -1297,6 +1309,42 @@ int b3ChangeDynamicsInfoSetLateralFriction(b3SharedMemoryCommandHandle commandHa
return 0;
}
int b3ChangeDynamicsInfoSetSpinningFriction(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double friction)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command->m_type == CMD_CHANGE_DYNAMICS_INFO);
command->m_changeDynamicsInfoArgs.m_bodyUniqueId = bodyUniqueId;
command->m_changeDynamicsInfoArgs.m_linkIndex = linkIndex;
command->m_changeDynamicsInfoArgs.m_spinningFriction = friction;
command->m_updateFlags |= CHANGE_DYNAMICS_INFO_SET_SPINNING_FRICTION;
return 0;
}
int b3ChangeDynamicsInfoSetRollingFriction(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double friction)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command->m_type == CMD_CHANGE_DYNAMICS_INFO);
command->m_changeDynamicsInfoArgs.m_bodyUniqueId = bodyUniqueId;
command->m_changeDynamicsInfoArgs.m_linkIndex = linkIndex;
command->m_changeDynamicsInfoArgs.m_rollingFriction = friction;
command->m_updateFlags |= CHANGE_DYNAMICS_INFO_SET_ROLLING_FRICTION;
return 0;
}
int b3ChangeDynamicsInfoSetRestitution(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double restitution)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command->m_type == CMD_CHANGE_DYNAMICS_INFO);
command->m_changeDynamicsInfoArgs.m_bodyUniqueId = bodyUniqueId;
command->m_changeDynamicsInfoArgs.m_linkIndex = linkIndex;
command->m_changeDynamicsInfoArgs.m_restitution = restitution;
command->m_updateFlags |= CHANGE_DYNAMICS_INFO_SET_RESTITUTION;
return 0;
}
b3SharedMemoryCommandHandle b3InitCreateUserConstraintCommand(b3PhysicsClientHandle physClient, int parentBodyIndex, int parentJointIndex, int childBodyIndex, int childJointIndex, struct b3JointInfo* info)
{
PhysicsClient* cl = (PhysicsClient* ) physClient;

10
examples/SharedMemory/PhysicsClientC_API.h
View File

@@ -84,7 +84,12 @@ int b3GetDynamicsInfo(b3SharedMemoryStatusHandle statusHandle, struct b3Dynamics
b3SharedMemoryCommandHandle b3InitChangeDynamicsInfo(b3PhysicsClientHandle physClient);
int b3ChangeDynamicsInfoSetMass(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double mass);
int b3ChangeDynamicsInfoSetLateralFriction(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double lateralFriction);
int b3ChangeDynamicsInfoSetSpinningFriction(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double friction);
int b3ChangeDynamicsInfoSetRollingFriction(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double friction);
int b3ChangeDynamicsInfoSetRestitution(b3SharedMemoryCommandHandle commandHandle, int bodyUniqueId, int linkIndex, double restitution);
b3SharedMemoryCommandHandle b3InitCreateUserConstraintCommand(b3PhysicsClientHandle physClient, int parentBodyIndex, int parentJointIndex, int childBodyIndex, int childJointIndex, struct b3JointInfo* info);
///return a unique id for the user constraint, after successful creation, or -1 for an invalid constraint id
@@ -222,6 +227,9 @@ int b3PhysicsParamSetSplitImpulsePenetrationThreshold(b3SharedMemoryCommandHandl
int b3PhysicsParamSetContactBreakingThreshold(b3SharedMemoryCommandHandle commandHandle, double contactBreakingThreshold);
int b3PhysicsParamSetMaxNumCommandsPer1ms(b3SharedMemoryCommandHandle commandHandle, int maxNumCmdPer1ms);
int b3PhysicsParamSetEnableFileCaching(b3SharedMemoryCommandHandle commandHandle, int enableFileCaching);
int b3PhysicsParamSetRestitutionVelocityThreshold(b3SharedMemoryCommandHandle commandHandle, double restitutionVelocityThreshold);
//b3PhysicsParamSetInternalSimFlags is for internal/temporary/easter-egg/experimental demo purposes
//Use at own risk: magic things may or my not happen when calling this API

148
examples/SharedMemory/PhysicsServerCommandProcessor.cpp
View File

@@ -3915,52 +3915,122 @@ bool PhysicsServerCommandProcessor::processCommand(const struct SharedMemoryComm
{
BT_PROFILE("CMD_CHANGE_DYNAMICS_INFO");
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_MASS)
{
int bodyUniqueId = clientCmd.m_changeDynamicsInfoArgs.m_bodyUniqueId;
int linkIndex = clientCmd.m_changeDynamicsInfoArgs.m_linkIndex;
double mass = clientCmd.m_changeDynamicsInfoArgs.m_mass;
btAssert(bodyUniqueId >= 0);
btAssert(linkIndex >= -1);
int bodyUniqueId = clientCmd.m_changeDynamicsInfoArgs.m_bodyUniqueId;
int linkIndex = clientCmd.m_changeDynamicsInfoArgs.m_linkIndex;
double mass = clientCmd.m_changeDynamicsInfoArgs.m_mass;
double lateralFriction = clientCmd.m_changeDynamicsInfoArgs.m_lateralFriction;
double spinningFriction = clientCmd.m_changeDynamicsInfoArgs.m_spinningFriction;
double rollingFriction = clientCmd.m_changeDynamicsInfoArgs.m_rollingFriction;
double restitution = clientCmd.m_changeDynamicsInfoArgs.m_restitution;
btAssert(bodyUniqueId >= 0);
btAssert(linkIndex >= -1);
InteralBodyData* body = m_data->m_bodyHandles.getHandle(bodyUniqueId);
if (body && body->m_multiBody)
InteralBodyData* body = m_data->m_bodyHandles.getHandle(bodyUniqueId);
if (body && body->m_multiBody)
{
btMultiBody* mb = body->m_multiBody;
if (linkIndex == -1)
{
btMultiBody* mb = body->m_multiBody;
if (linkIndex == -1)
if (mb->getBaseCollider())
{
mb->setBaseMass(mass);
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_RESTITUTION)
{
mb->getBaseCollider()->setRestitution(restitution);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_LATERAL_FRICTION)
{
mb->getBaseCollider()->setFriction(lateralFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_SPINNING_FRICTION)
{
mb->getBaseCollider()->setSpinningFriction(spinningFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_ROLLING_FRICTION)
{
mb->getBaseCollider()->setRollingFriction(rollingFriction);
}
}
else
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_MASS)
{
mb->setBaseMass(mass);
if (mb->getBaseCollider() && mb->getBaseCollider()->getCollisionShape())
{
btVector3 localInertia;
mb->getBaseCollider()->getCollisionShape()->calculateLocalInertia(mass,localInertia);
mb->setBaseInertia(localInertia);
}
}
}
else
{
if (mb->getLinkCollider(linkIndex))
{
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_RESTITUTION)
{
mb->getLinkCollider(linkIndex)->setRestitution(restitution);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_SPINNING_FRICTION)
{
mb->getLinkCollider(linkIndex)->setSpinningFriction(spinningFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_ROLLING_FRICTION)
{
mb->getLinkCollider(linkIndex)->setRollingFriction(rollingFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_LATERAL_FRICTION)
{
mb->getLinkCollider(linkIndex)->setFriction(lateralFriction);
}
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_MASS)
{
mb->getLink(linkIndex).m_mass = mass;
if (mb->getLinkCollider(linkIndex) && mb->getLinkCollider(linkIndex)->getCollisionShape())
{
btVector3 localInertia;
mb->getLinkCollider(linkIndex)->getCollisionShape()->calculateLocalInertia(mass,localInertia);
mb->getLink(linkIndex).m_inertiaLocal = localInertia;
}
}
}
} else
{
if (body && body->m_rigidBody)
{
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_RESTITUTION)
{
body->m_rigidBody->setRestitution(restitution);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_LATERAL_FRICTION)
{
body->m_rigidBody->setFriction(lateralFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_SPINNING_FRICTION)
{
body->m_rigidBody->setSpinningFriction(spinningFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_ROLLING_FRICTION)
{
body->m_rigidBody->setRollingFriction(rollingFriction);
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_MASS)
{
btVector3 localInertia;
if (body->m_rigidBody->getCollisionShape())
{
body->m_rigidBody->getCollisionShape()->calculateLocalInertia(mass,localInertia);
}
body->m_rigidBody->setMassProps(mass,localInertia);
}
}
}
if (clientCmd.m_updateFlags & CHANGE_DYNAMICS_INFO_SET_LATERAL_FRICTION)
{
int bodyUniqueId = clientCmd.m_changeDynamicsInfoArgs.m_bodyUniqueId;
int linkIndex = clientCmd.m_changeDynamicsInfoArgs.m_linkIndex;
double lateralFriction = clientCmd.m_changeDynamicsInfoArgs.m_lateralFriction;
btAssert(bodyUniqueId >= 0);
btAssert(linkIndex >= -1);
InteralBodyData* body = m_data->m_bodyHandles.getHandle(bodyUniqueId);
if (body && body->m_multiBody)
{
btMultiBody* mb = body->m_multiBody;
if (linkIndex == -1)
{
mb->getBaseCollider()->setFriction(lateralFriction);
}
else
{
mb->getLinkCollider(linkIndex)->setFriction(lateralFriction);
}
}
}
SharedMemoryStatus& serverCmd =serverStatusOut;
serverCmd.m_type = CMD_CLIENT_COMMAND_COMPLETED;
@@ -4070,6 +4140,12 @@ bool PhysicsServerCommandProcessor::processCommand(const struct SharedMemoryComm
{
m_data->m_dynamicsWorld->getSolverInfo().m_erp2 = clientCmd.m_physSimParamArgs.m_defaultContactERP;
}
if (clientCmd.m_updateFlags&SIM_PARAM_UPDATE_RESTITUTION_VELOCITY_THRESHOLD)
{
m_data->m_dynamicsWorld->getSolverInfo().m_restitutionVelocityThreshold = clientCmd.m_physSimParamArgs.m_restitutionVelocityThreshold;
}
if (clientCmd.m_updateFlags&SIM_PARAM_ENABLE_FILE_CACHING)
{

9
examples/SharedMemory/SharedMemoryCommands.h
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@@ -114,6 +114,9 @@ enum EnumChangeDynamicsInfoFlags
CHANGE_DYNAMICS_INFO_SET_MASS=1,
CHANGE_DYNAMICS_INFO_SET_COM=2,
CHANGE_DYNAMICS_INFO_SET_LATERAL_FRICTION=4,
CHANGE_DYNAMICS_INFO_SET_SPINNING_FRICTION=8,
CHANGE_DYNAMICS_INFO_SET_ROLLING_FRICTION=16,
CHANGE_DYNAMICS_INFO_SET_RESTITUTION=32,
};
struct ChangeDynamicsInfoArgs
@@ -123,6 +126,9 @@ struct ChangeDynamicsInfoArgs
double m_mass;
double m_COM[3];
double m_lateralFriction;
double m_spinningFriction;
double m_rollingFriction;
double m_restitution;
};
struct GetDynamicsInfoArgs
@@ -354,6 +360,8 @@ enum EnumSimParamUpdateFlags
SIM_PARAM_UPDATE_CONTACT_BREAKING_THRESHOLD = 1024,
SIM_PARAM_MAX_CMD_PER_1MS = 2048,
SIM_PARAM_ENABLE_FILE_CACHING = 4096,
SIM_PARAM_UPDATE_RESTITUTION_VELOCITY_THRESHOLD = 8192,
};
@@ -387,6 +395,7 @@ struct SendPhysicsSimulationParameters
double m_defaultContactERP;
int m_collisionFilterMode;
int m_enableFileCaching;
double m_restitutionVelocityThreshold;
};
struct LoadBunnyArgs

38
examples/pybullet/examples/restitution.py Normal file
View File

@@ -0,0 +1,38 @@
#you can set the restitution (bouncyness) of an object in the URDF file
#or using changeDynamics
import pybullet as p
import time
p.connect(p.GUI)
restitutionId = p.addUserDebugParameter("restitution",0,1,1)
restitutionVelocityThresholdId = p.addUserDebugParameter("res. vel. threshold",0,3,0.2)
lateralFrictionId = p.addUserDebugParameter("lateral friction",0,1,0.5)
spinningFrictionId = p.addUserDebugParameter("spinning friction",0,1,0.03)
rollingFrictionId = p.addUserDebugParameter("rolling friction",0,1,0.03)
plane = p.loadURDF("plane_with_restitution.urdf")
sphere = p.loadURDF("sphere_with_restitution.urdf",[0,0,2])
p.setRealTimeSimulation(1)
p.setGravity(0,0,-10)
while (1):
restitution = p.readUserDebugParameter(restitutionId)
restitutionVelocityThreshold = p.readUserDebugParameter(restitutionVelocityThresholdId)
p.setPhysicsEngineParameter(restitutionVelocityThreshold=restitutionVelocityThreshold)
lateralFriction = p.readUserDebugParameter(lateralFrictionId)
spinningFriction = p.readUserDebugParameter(spinningFrictionId)
rollingFriction = p.readUserDebugParameter(rollingFrictionId)
p.changeDynamics(plane,-1,lateralFriction=1)
p.changeDynamics(sphere,-1,lateralFriction=lateralFriction)
p.changeDynamics(sphere,-1,spinningFriction=spinningFriction)
p.changeDynamics(sphere,-1,rollingFriction=rollingFriction)
p.changeDynamics(plane,-1,restitution=restitution)
p.changeDynamics(sphere,-1,restitution=restitution)
pos,orn=p.getBasePositionAndOrientation(sphere)
#print("pos=")
#print(pos)
time.sleep(0.01)

37
examples/pybullet/pybullet.c
View File

@@ -620,11 +620,15 @@ static PyObject* pybullet_changeDynamicsInfo(PyObject* self, PyObject* args, PyO
int linkIndex = -2;
double mass = -1;
double lateralFriction = -1;
double spinningFriction= -1;
double rollingFriction = -1;
double restitution = -1;
b3PhysicsClientHandle sm = 0;
int physicsClientId = 0;
static char* kwlist[] = {"bodyUniqueId", "linkIndex", "mass", "lateralFriction", "physicsClientId", NULL};
if (!PyArg_ParseTupleAndKeywords(args, keywds, "ii|ddi", kwlist, &bodyUniqueId, &linkIndex,&mass, &lateralFriction, &physicsClientId))
static char* kwlist[] = {"bodyUniqueId", "linkIndex", "mass", "lateralFriction", "spinningFriction", "rollingFriction","restitution", "physicsClientId", NULL};
if (!PyArg_ParseTupleAndKeywords(args, keywds, "ii|dddddi", kwlist, &bodyUniqueId, &linkIndex,&mass, &lateralFriction, &spinningFriction, &rollingFriction, &restitution, &physicsClientId))
{
return NULL;
}
@@ -644,12 +648,23 @@ static PyObject* pybullet_changeDynamicsInfo(PyObject* self, PyObject* args, PyO
{
b3ChangeDynamicsInfoSetMass(command, bodyUniqueId, linkIndex, mass);
}
if (lateralFriction >= 0)
{
b3ChangeDynamicsInfoSetLateralFriction(command, bodyUniqueId, linkIndex, lateralFriction);
}
if (spinningFriction>=0)
{
b3ChangeDynamicsInfoSetSpinningFriction(command, bodyUniqueId, linkIndex,spinningFriction);
}
if (rollingFriction>=0)
{
b3ChangeDynamicsInfoSetRollingFriction(command, bodyUniqueId, linkIndex,rollingFriction);
}
if (restitution>=0)
{
b3ChangeDynamicsInfoSetRestitution(command, bodyUniqueId, linkIndex, restitution);
}
statusHandle = b3SubmitClientCommandAndWaitStatus(sm, command);
}
@@ -725,14 +740,14 @@ static PyObject* pybullet_setPhysicsEngineParameter(PyObject* self, PyObject* ar
double contactBreakingThreshold = -1;
int maxNumCmdPer1ms = -2;
int enableFileCaching = -1;
double restitutionVelocityThreshold=-1;
b3PhysicsClientHandle sm = 0;
int physicsClientId = 0;
static char* kwlist[] = {"fixedTimeStep", "numSolverIterations", "useSplitImpulse", "splitImpulsePenetrationThreshold", "numSubSteps", "collisionFilterMode", "contactBreakingThreshold", "maxNumCmdPer1ms", "enableFileCaching","physicsClientId", NULL};
static char* kwlist[] = {"fixedTimeStep", "numSolverIterations", "useSplitImpulse", "splitImpulsePenetrationThreshold", "numSubSteps", "collisionFilterMode", "contactBreakingThreshold", "maxNumCmdPer1ms", "enableFileCaching","restitutionVelocityThreshold", "physicsClientId", NULL};
if (!PyArg_ParseTupleAndKeywords(args, keywds, "|diidiidiii", kwlist, &fixedTimeStep, &numSolverIterations, &useSplitImpulse, &splitImpulsePenetrationThreshold, &numSubSteps,
&collisionFilterMode, &contactBreakingThreshold, &maxNumCmdPer1ms, &enableFileCaching, &physicsClientId))
if (!PyArg_ParseTupleAndKeywords(args, keywds, "|diidiidiidi", kwlist, &fixedTimeStep, &numSolverIterations, &useSplitImpulse, &splitImpulsePenetrationThreshold, &numSubSteps,
&collisionFilterMode, &contactBreakingThreshold, &maxNumCmdPer1ms, &enableFileCaching, &restitutionVelocityThreshold, &physicsClientId))
{
return NULL;
}
@@ -783,6 +798,10 @@ static PyObject* pybullet_setPhysicsEngineParameter(PyObject* self, PyObject* ar
b3PhysicsParamSetMaxNumCommandsPer1ms(command, maxNumCmdPer1ms);
}
if (restitutionVelocityThreshold>=0)
{
b3PhysicsParamSetRestitutionVelocityThreshold(command, restitutionVelocityThreshold);
}
if (enableFileCaching>=0)
{
b3PhysicsParamSetEnableFileCaching(command, enableFileCaching);
@@ -921,7 +940,7 @@ static PyObject* pybullet_loadURDF(PyObject* self, PyObject* args, PyObject* key
startOrnZ, startOrnW);
if (useMaximalCoordinates>=0)
{
b3LoadUrdfCommandSetUseMultiBody(command, useMaximalCoordinates);
b3LoadUrdfCommandSetUseMultiBody(command, useMaximalCoordinates==0);
}
if (useFixedBase)
{