void
CGrassSticks::simulationTickCallback(btDynamicsWorld *dynamicsWorld, btScalar timeStep)
{
//if (mField)
{
const btSoftBodyArray& softBodyArray = static_cast<btSoftRigidDynamicsWorld*>(dynamicsWorld)->getSoftBodyArray();
int numSoftBodys = softBodyArray.size();
btVector3 rot0(0,0,0);
for (int i=0;i<numSoftBodys;++i)
{
btSoftBody* psb = softBodyArray[i];
int linksize = psb->m_links.size();
rot0.setZero();
for(int k=0;k<linksize;++k)
{
const btSoftBody::Link& l=psb->m_links[k];
rot0 += l.m_n[1]->m_x-l.m_n[0]->m_x;
}
const btVector3& pos0 = psb->m_nodes[0].m_x;
Ogre::Vector4 offset(-rot0.getX(), -rot0.getY()/2.0f, -rot0.getZ(), 0);
Ogre::Vector4 pos(pos0.getX(), pos0.getY(), pos0.getZ(), 0);
Ogre::Renderable* rend = static_cast<Ogre::Renderable*>(psb->getUserPointer());
if (rend)
{
rend->setCustomParameter(999, offset);
}
}
} // End if
}
void
RankTwoTensorTest::rotateTest()
{
Real sqrt2 = 0.707106781187;
RealTensorValue rtv0(sqrt2, -sqrt2, 0, sqrt2, sqrt2, 0, 0, 0, 1); // rotation about "0" axis
RealTensorValue rtv1(sqrt2, 0, -sqrt2, 0, 1, 0, sqrt2, 0, sqrt2); // rotation about "1" axis
RealTensorValue rtv2(1, 0, 0, 0, sqrt2, -sqrt2, 0, sqrt2, sqrt2); // rotation about "2" axis
RankTwoTensor rot0(rtv0);
RankTwoTensor rot0T = rot0.transpose();
RankTwoTensor rot1(rtv1);
RankTwoTensor rot1T = rot1.transpose();
RankTwoTensor rot2(rtv2);
RankTwoTensor rot2T = rot2.transpose();
RankTwoTensor rot = rot0*rot1*rot2;
RankTwoTensor answer;
RankTwoTensor m3;
// the following "answer"s come from mathematica of course!
// rotate about "0" axis with RealTensorValue, then back again with RankTwoTensor
m3 = _m3;
answer = RankTwoTensor(-4, 3, 6.363961, 3, 0, -2.1213403, 6.363961, -2.1213403, 9);
m3.rotate(rtv0);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - answer).L2norm(), 0.0001);
m3.rotate(rot0T);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - _m3).L2norm(), 0.0001);
// rotate about "1" axis with RealTensorValue, then back again with RankTwoTensor
m3 = _m3;
answer = RankTwoTensor(2, 5.656854, -4, 5.656854, -5, -2.828427, -4, -2.828427, 8);
m3.rotate(rtv1);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - answer).L2norm(), 0.0001);
m3.rotate(rot1T);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - _m3).L2norm(), 0.0001);
// rotate about "2" axis with RealTensorValue, then back again with RankTwoTensor
m3 = _m3;
answer = RankTwoTensor(1, -sqrt2, 3.5355339, -sqrt2, 8, -7, 3.5355339, -7, -4);
m3.rotate(rtv2);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - answer).L2norm(), 0.0001);
m3.rotate(rot2T);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - _m3).L2norm(), 0.0001);
// rotate with "rot"
m3 = _m3;
answer = RankTwoTensor(-2.9675144, -6.51776695, 5.6213203, -6.51776695, 5.9319805, -2.0857864, 5.6213203, -2.0857864, 2.0355339);
m3.rotate(rot);
CPPUNIT_ASSERT_DOUBLES_EQUAL(0, (m3 - answer).L2norm(), 0.0001);
}
