bullet3/examples/CommonInterfaces/CommonMultiBodyBase.h
erwincoumans ad29d27700 add initial inverse dynamics example skeleton, with urdf and programmatically created btMultiBody.
disabled in Bullet/examples/ExampleBrowser/ExampleEntries.cpp
2015-11-13 10:37:43 -08:00

459 lines
12 KiB
C++

#ifndef COMMON_MULTI_BODY_SETUP_H
#define COMMON_MULTI_BODY_SETUP_H
#include "btBulletDynamicsCommon.h"
#include "BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.h"
#include "BulletDynamics/Featherstone/btMultiBodyConstraintSolver.h"
#include "BulletDynamics/Featherstone/btMultiBodyPoint2Point.h"
#include "BulletDynamics/Featherstone/btMultiBodyLinkCollider.h"
#include "btBulletDynamicsCommon.h"
#include "CommonExampleInterface.h"
#include "CommonGUIHelperInterface.h"
#include "CommonRenderInterface.h"
#include "CommonGraphicsAppInterface.h"
#include "CommonWindowInterface.h"
#include "CommonCameraInterface.h"
struct CommonMultiBodyBase : public CommonExampleInterface
{
//keep the collision shapes, for deletion/cleanup
btAlignedObjectArray<btCollisionShape*> m_collisionShapes;
btBroadphaseInterface* m_broadphase;
btCollisionDispatcher* m_dispatcher;
btMultiBodyConstraintSolver* m_solver;
btDefaultCollisionConfiguration* m_collisionConfiguration;
btMultiBodyDynamicsWorld* m_dynamicsWorld;
//data for picking objects
class btRigidBody* m_pickedBody;
class btTypedConstraint* m_pickedConstraint;
class btMultiBodyPoint2Point* m_pickingMultiBodyPoint2Point;
btVector3 m_oldPickingPos;
btVector3 m_hitPos;
btScalar m_oldPickingDist;
bool m_prevCanSleep;
struct GUIHelperInterface* m_guiHelper;
CommonMultiBodyBase(GUIHelperInterface* helper)
:m_broadphase(0),
m_dispatcher(0),
m_solver(0),
m_collisionConfiguration(0),
m_dynamicsWorld(0),
m_pickedBody(0),
m_pickedConstraint(0),
m_pickingMultiBodyPoint2Point(0),
m_prevCanSleep(false),
m_guiHelper(helper)
{
}
virtual void createEmptyDynamicsWorld()
{
///collision configuration contains default setup for memory, collision setup
m_collisionConfiguration = new btDefaultCollisionConfiguration();
//m_collisionConfiguration->setConvexConvexMultipointIterations();
///use the default collision dispatcher. For parallel processing you can use a diffent dispatcher (see Extras/BulletMultiThreaded)
m_dispatcher = new btCollisionDispatcher(m_collisionConfiguration);
m_broadphase = new btDbvtBroadphase();
m_solver = new btMultiBodyConstraintSolver;
m_dynamicsWorld = new btMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, m_solver, m_collisionConfiguration);
m_dynamicsWorld->setGravity(btVector3(0, -10, 0));
}
virtual void stepSimulation(float deltaTime)
{
if (m_dynamicsWorld)
{
m_dynamicsWorld->stepSimulation(deltaTime);
}
}
virtual void exitPhysics()
{
removePickingConstraint();
//cleanup in the reverse order of creation/initialization
//remove the rigidbodies from the dynamics world and delete them
if (m_dynamicsWorld)
{
int i;
for (i = m_dynamicsWorld->getNumConstraints() - 1; i >= 0; i--)
{
m_dynamicsWorld->removeConstraint(m_dynamicsWorld->getConstraint(i));
}
for (i = m_dynamicsWorld->getNumCollisionObjects() - 1; i >= 0; i--)
{
btCollisionObject* obj = m_dynamicsWorld->getCollisionObjectArray()[i];
btRigidBody* body = btRigidBody::upcast(obj);
if (body && body->getMotionState())
{
delete body->getMotionState();
}
m_dynamicsWorld->removeCollisionObject(obj);
delete obj;
}
}
//delete collision shapes
for (int j = 0; j<m_collisionShapes.size(); j++)
{
btCollisionShape* shape = m_collisionShapes[j];
delete shape;
}
m_collisionShapes.clear();
delete m_dynamicsWorld;
m_dynamicsWorld = 0;
delete m_solver;
m_solver=0;
delete m_broadphase;
m_broadphase=0;
delete m_dispatcher;
m_dispatcher=0;
delete m_collisionConfiguration;
m_collisionConfiguration=0;
}
virtual void syncPhysicsToGraphics()
{
if (m_dynamicsWorld)
{
m_guiHelper->syncPhysicsToGraphics(m_dynamicsWorld);
}
}
virtual void renderScene()
{
if (m_dynamicsWorld)
{
m_guiHelper->syncPhysicsToGraphics(m_dynamicsWorld);
m_guiHelper->render(m_dynamicsWorld);
}
}
virtual void physicsDebugDraw(int debugDrawFlags)
{
if (m_dynamicsWorld)
{
if (m_dynamicsWorld->getDebugDrawer())
{
m_dynamicsWorld->getDebugDrawer()->setDebugMode(debugDrawFlags);
}
m_dynamicsWorld->debugDrawWorld();
}
}
virtual bool keyboardCallback(int key, int state)
{
return false;//don't handle this key
}
btVector3 getRayTo(int x,int y)
{
CommonRenderInterface* renderer = m_guiHelper->getRenderInterface();
if (!renderer)
{
btAssert(0);
return btVector3(0,0,0);
}
float top = 1.f;
float bottom = -1.f;
float nearPlane = 1.f;
float tanFov = (top-bottom)*0.5f / nearPlane;
float fov = btScalar(2.0) * btAtan(tanFov);
btVector3 camPos,camTarget;
renderer->getActiveCamera()->getCameraPosition(camPos);
renderer->getActiveCamera()->getCameraTargetPosition(camTarget);
btVector3 rayFrom = camPos;
btVector3 rayForward = (camTarget-camPos);
rayForward.normalize();
float farPlane = 10000.f;
rayForward*= farPlane;
btVector3 rightOffset;
btVector3 cameraUp=btVector3(0,0,0);
cameraUp[m_guiHelper->getAppInterface()->getUpAxis()]=1;
btVector3 vertical = cameraUp;
btVector3 hor;
hor = rayForward.cross(vertical);
hor.normalize();
vertical = hor.cross(rayForward);
vertical.normalize();
float tanfov = tanf(0.5f*fov);
hor *= 2.f * farPlane * tanfov;
vertical *= 2.f * farPlane * tanfov;
btScalar aspect;
float width = float(renderer->getScreenWidth());
float height = float (renderer->getScreenHeight());
aspect = width / height;
hor*=aspect;
btVector3 rayToCenter = rayFrom + rayForward;
btVector3 dHor = hor * 1.f/width;
btVector3 dVert = vertical * 1.f/height;
btVector3 rayTo = rayToCenter - 0.5f * hor + 0.5f * vertical;
rayTo += btScalar(x) * dHor;
rayTo -= btScalar(y) * dVert;
return rayTo;
}
virtual bool mouseMoveCallback(float x,float y)
{
CommonRenderInterface* renderer = m_guiHelper->getRenderInterface();
if (!renderer)
{
btAssert(0);
return false;
}
btVector3 rayTo = getRayTo(int(x), int(y));
btVector3 rayFrom;
renderer->getActiveCamera()->getCameraPosition(rayFrom);
movePickedBody(rayFrom,rayTo);
return false;
}
virtual bool mouseButtonCallback(int button, int state, float x, float y)
{
CommonRenderInterface* renderer = m_guiHelper->getRenderInterface();
if (!renderer)
{
btAssert(0);
return false;
}
CommonWindowInterface* window = m_guiHelper->getAppInterface()->m_window;
if (state==1)
{
if(button==0 && (!window->isModifierKeyPressed(B3G_ALT) && !window->isModifierKeyPressed(B3G_CONTROL) ))
{
btVector3 camPos;
renderer->getActiveCamera()->getCameraPosition(camPos);
btVector3 rayFrom = camPos;
btVector3 rayTo = getRayTo(int(x),int(y));
pickBody(rayFrom, rayTo);
}
} else
{
if (button==0)
{
removePickingConstraint();
//remove p2p
}
}
//printf("button=%d, state=%d\n",button,state);
return false;
}
virtual bool pickBody(const btVector3& rayFromWorld, const btVector3& rayToWorld)
{
if (m_dynamicsWorld==0)
return false;
btCollisionWorld::ClosestRayResultCallback rayCallback(rayFromWorld, rayToWorld);
m_dynamicsWorld->rayTest(rayFromWorld, rayToWorld, rayCallback);
if (rayCallback.hasHit())
{
btVector3 pickPos = rayCallback.m_hitPointWorld;
btRigidBody* body = (btRigidBody*)btRigidBody::upcast(rayCallback.m_collisionObject);
if (body)
{
//other exclusions?
if (!(body->isStaticObject() || body->isKinematicObject()))
{
m_pickedBody = body;
m_pickedBody->setActivationState(DISABLE_DEACTIVATION);
//printf("pickPos=%f,%f,%f\n",pickPos.getX(),pickPos.getY(),pickPos.getZ());
btVector3 localPivot = body->getCenterOfMassTransform().inverse() * pickPos;
btPoint2PointConstraint* p2p = new btPoint2PointConstraint(*body, localPivot);
m_dynamicsWorld->addConstraint(p2p, true);
m_pickedConstraint = p2p;
btScalar mousePickClamping = 30.f;
p2p->m_setting.m_impulseClamp = mousePickClamping;
//very weak constraint for picking
p2p->m_setting.m_tau = 0.001f;
}
} else
{
btMultiBodyLinkCollider* multiCol = (btMultiBodyLinkCollider*)btMultiBodyLinkCollider::upcast(rayCallback.m_collisionObject);
if (multiCol && multiCol->m_multiBody)
{
m_prevCanSleep = multiCol->m_multiBody->getCanSleep();
multiCol->m_multiBody->setCanSleep(false);
btVector3 pivotInA = multiCol->m_multiBody->worldPosToLocal(multiCol->m_link, pickPos);
btMultiBodyPoint2Point* p2p = new btMultiBodyPoint2Point(multiCol->m_multiBody,multiCol->m_link,0,pivotInA,pickPos);
//if you add too much energy to the system, causing high angular velocities, simulation 'explodes'
//see also http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?f=4&t=949
//so we try to avoid it by clamping the maximum impulse (force) that the mouse pick can apply
//it is not satisfying, hopefully we find a better solution (higher order integrator, using joint friction using a zero-velocity target motor with limited force etc?)
btScalar scaling=1;
p2p->setMaxAppliedImpulse(2*scaling);
btMultiBodyDynamicsWorld* world = (btMultiBodyDynamicsWorld*) m_dynamicsWorld;
world->addMultiBodyConstraint(p2p);
m_pickingMultiBodyPoint2Point =p2p;
}
}
// pickObject(pickPos, rayCallback.m_collisionObject);
m_oldPickingPos = rayToWorld;
m_hitPos = pickPos;
m_oldPickingDist = (pickPos - rayFromWorld).length();
// printf("hit !\n");
//add p2p
}
return false;
}
virtual bool movePickedBody(const btVector3& rayFromWorld, const btVector3& rayToWorld)
{
if (m_pickedBody && m_pickedConstraint)
{
btPoint2PointConstraint* pickCon = static_cast<btPoint2PointConstraint*>(m_pickedConstraint);
if (pickCon)
{
//keep it at the same picking distance
btVector3 dir = rayToWorld-rayFromWorld;
dir.normalize();
dir *= m_oldPickingDist;
btVector3 newPivotB = rayFromWorld + dir;
pickCon->setPivotB(newPivotB);
}
}
if (m_pickingMultiBodyPoint2Point)
{
//keep it at the same picking distance
btVector3 dir = rayToWorld-rayFromWorld;
dir.normalize();
dir *= m_oldPickingDist;
btVector3 newPivotB = rayFromWorld + dir;
m_pickingMultiBodyPoint2Point->setPivotInB(newPivotB);
}
return false;
}
virtual void removePickingConstraint()
{
if (m_pickedConstraint)
{
m_dynamicsWorld->removeConstraint(m_pickedConstraint);
delete m_pickedConstraint;
m_pickedConstraint = 0;
m_pickedBody = 0;
}
if (m_pickingMultiBodyPoint2Point)
{
m_pickingMultiBodyPoint2Point->getMultiBodyA()->setCanSleep(m_prevCanSleep);
btMultiBodyDynamicsWorld* world = (btMultiBodyDynamicsWorld*) m_dynamicsWorld;
world->removeMultiBodyConstraint(m_pickingMultiBodyPoint2Point);
delete m_pickingMultiBodyPoint2Point;
m_pickingMultiBodyPoint2Point = 0;
}
}
btBoxShape* createBoxShape(const btVector3& halfExtents)
{
btBoxShape* box = new btBoxShape(halfExtents);
return box;
}
btRigidBody* createRigidBody(float mass, const btTransform& startTransform, btCollisionShape* shape, const btVector4& color = btVector4(1, 0, 0, 1))
{
btAssert((!shape || shape->getShapeType() != INVALID_SHAPE_PROXYTYPE));
//rigidbody is dynamic if and only if mass is non zero, otherwise static
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
shape->calculateLocalInertia(mass, localInertia);
//using motionstate is recommended, it provides interpolation capabilities, and only synchronizes 'active' objects
#define USE_MOTIONSTATE 1
#ifdef USE_MOTIONSTATE
btDefaultMotionState* myMotionState = new btDefaultMotionState(startTransform);
btRigidBody::btRigidBodyConstructionInfo cInfo(mass, myMotionState, shape, localInertia);
btRigidBody* body = new btRigidBody(cInfo);
//body->setContactProcessingThreshold(m_defaultContactProcessingThreshold);
#else
btRigidBody* body = new btRigidBody(mass, 0, shape, localInertia);
body->setWorldTransform(startTransform);
#endif//
body->setUserIndex(-1);
m_dynamicsWorld->addRigidBody(body);
return body;
}
};
#endif //COMMON_MULTI_BODY_SETUP_H