void ODERigidObject::Create(dWorldID worldID,dSpaceID space,bool useBoundaryLayer)
{
Clear();
spaceID = space;
bodyID = dBodyCreate(worldID);
dMass mass;
mass.mass = obj.mass;
//NOTE: in ODE, COM must be zero vector! -- we take care of this by shifting geometry
//CopyVector3(mass.c,obj.com);
mass.c[0] = mass.c[1] = mass.c[2] = 0; mass.c[3] = 1.0;
CopyMatrix(mass.I,obj.inertia);
int res=dMassCheck(&mass);
if(res != 1) {
fprintf(stderr,"Uh... mass is not considered to be valid by ODE?\n");
std::cerr<<"Inertia: "<<obj.inertia<<std::endl;
}
dBodySetMass(bodyID,&mass);
geometry = new ODEGeometry;
geometry->Create(&obj.geometry,spaceID,-obj.com,useBoundaryLayer);
dGeomSetBody(geometry->geom(),bodyID);
dGeomSetData(geometry->geom(),(void*)-1);
geometry->SetPadding(defaultPadding);
geometry->surf().kRestitution = obj.kRestitution;
geometry->surf().kFriction = obj.kFriction;
geometry->surf().kStiffness = obj.kStiffness;
geometry->surf().kDamping = obj.kDamping;
SetTransform(obj.T);
}
void dMassRotate (dMass *m, const dMatrix3 R)
{
// if the body is rotated by `R' relative to its point of reference,
// the new inertia about the point of reference is:
//
// R * I * R'
//
// where I is the old inertia.
dMatrix3 t1;
dReal t2[3];
dAASSERT (m);
// rotate inertia matrix
dMultiply2_333 (t1,m->I,R);
dMultiply0_333 (m->I,R,t1);
// ensure perfect symmetry
m->_I(1,0) = m->_I(0,1);
m->_I(2,0) = m->_I(0,2);
m->_I(2,1) = m->_I(1,2);
// rotate center of mass
dMultiply0_331 (t2,R,m->c);
m->c[0] = t2[0];
m->c[1] = t2[1];
m->c[2] = t2[2];
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassAdjust (dMass *m, dReal newmass)
{
dAASSERT (m);
dReal scale = newmass / m->mass;
m->mass = newmass;
for (int i=0; i<3; i++) for (int j=0; j<3; j++) m->_I(i,j) *= scale;
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassSetBoxTotal (dMass *m, dReal total_mass,
dReal lx, dReal ly, dReal lz)
{
dAASSERT (m);
dMassSetZero (m);
m->mass = total_mass;
m->_I(0,0) = total_mass/REAL(12.0) * (ly*ly + lz*lz);
m->_I(1,1) = total_mass/REAL(12.0) * (lx*lx + lz*lz);
m->_I(2,2) = total_mass/REAL(12.0) * (lx*lx + ly*ly);
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassSetSphereTotal (dMass *m, dReal total_mass, dReal radius)
{
dAASSERT (m);
dMassSetZero (m);
m->mass = total_mass;
dReal II = REAL(0.4) * total_mass * radius*radius;
m->_I(0,0) = II;
m->_I(1,1) = II;
m->_I(2,2) = II;
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassSetCylinderTotal (dMass *m, dReal total_mass, int direction,
dReal radius, dReal length)
{
dReal r2,I;
dAASSERT (m);
dUASSERT (direction >= 1 && direction <= 3,"bad direction number");
dMassSetZero (m);
r2 = radius*radius;
m->mass = total_mass;
I = total_mass*(REAL(0.25)*r2 + (REAL(1.0)/REAL(12.0))*length*length);
m->_I(0,0) = I;
m->_I(1,1) = I;
m->_I(2,2) = I;
m->_I(direction-1,direction-1) = total_mass*REAL(0.5)*r2;
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassTranslate (dMass *m, dReal x, dReal y, dReal z)
{
// if the body is translated by `a' relative to its point of reference,
// the new inertia about the point of reference is:
//
// I + mass*(crossmat(c)^2 - crossmat(c+a)^2)
//
// where c is the existing center of mass and I is the old inertia.
int i,j;
dMatrix3 ahat,chat,t1,t2;
dReal a[3];
dAASSERT (m);
// adjust inertia matrix
dSetZero (chat,12);
dSetCrossMatrixPlus (chat,m->c,4);
a[0] = x + m->c[0];
a[1] = y + m->c[1];
a[2] = z + m->c[2];
dSetZero (ahat,12);
dSetCrossMatrixPlus (ahat,a,4);
dMultiply0_333 (t1,ahat,ahat);
dMultiply0_333 (t2,chat,chat);
for (i=0; i<3; i++) for (j=0; j<3; j++)
m->_I(i,j) += m->mass * (t2[i*4+j]-t1[i*4+j]);
// ensure perfect symmetry
m->_I(1,0) = m->_I(0,1);
m->_I(2,0) = m->_I(0,2);
m->_I(2,1) = m->_I(1,2);
// adjust center of mass
m->c[0] += x;
m->c[1] += y;
m->c[2] += z;
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
void dMassSetParameters (dMass *m, dReal themass,
dReal cgx, dReal cgy, dReal cgz,
dReal I11, dReal I22, dReal I33,
dReal I12, dReal I13, dReal I23)
{
dAASSERT (m);
dMassSetZero (m);
m->mass = themass;
m->c[0] = cgx;
m->c[1] = cgy;
m->c[2] = cgz;
m->_I(0,0) = I11;
m->_I(1,1) = I22;
m->_I(2,2) = I33;
m->_I(0,1) = I12;
m->_I(0,2) = I13;
m->_I(1,2) = I23;
m->_I(1,0) = I12;
m->_I(2,0) = I13;
m->_I(2,1) = I23;
dMassCheck (m);
}
void dMassSetCapsule (dMass *m, dReal density, int direction,
dReal radius, dReal length)
{
dReal M1,M2,Ia,Ib;
dAASSERT (m);
dUASSERT (direction >= 1 && direction <= 3,"bad direction number");
dMassSetZero (m);
M1 = (dReal) (M_PI*radius*radius*length*density); // cylinder mass
M2 = (dReal) ((REAL(4.0)/REAL(3.0))*M_PI*radius*radius*radius*density); // total cap mass
m->mass = M1+M2;
Ia = M1*(REAL(0.25)*radius*radius + (REAL(1.0)/REAL(12.0))*length*length) +
M2*(REAL(0.4)*radius*radius + REAL(0.375)*radius*length + REAL(0.25)*length*length);
Ib = (M1*REAL(0.5) + M2*REAL(0.4))*radius*radius;
m->_I(0,0) = Ia;
m->_I(1,1) = Ia;
m->_I(2,2) = Ia;
m->_I(direction-1,direction-1) = Ib;
# ifndef dNODEBUG
dMassCheck (m);
# endif
}
/*
* dMassSetTrimesh, implementation by Gero Mueller.
* Based on Brian Mirtich, "Fast and Accurate Computation of
* Polyhedral Mass Properties," journal of graphics tools, volume 1,
* number 2, 1996.
*/
void dMassSetTrimesh( dMass *m, dReal density, dGeomID g )
{
dAASSERT (m);
dUASSERT(g && g->type == dTriMeshClass, "argument not a trimesh");
dMassSetZero (m);
#if dTRIMESH_ENABLED
dxTriMesh *TriMesh = (dxTriMesh *)g;
unsigned int triangles = FetchTriangleCount( TriMesh );
dReal nx, ny, nz;
unsigned int i, A, B, C;
// face integrals
dReal Fa, Fb, Fc, Faa, Fbb, Fcc, Faaa, Fbbb, Fccc, Faab, Fbbc, Fcca;
// projection integrals
dReal P1, Pa, Pb, Paa, Pab, Pbb, Paaa, Paab, Pabb, Pbbb;
dReal T0 = 0;
dReal T1[3] = {0., 0., 0.};
dReal T2[3] = {0., 0., 0.};
dReal TP[3] = {0., 0., 0.};
for( i = 0; i < triangles; i++ )
{
dVector3 v[3];
FetchTransformedTriangle( TriMesh, i, v);
dVector3 n, a, b;
dSubtractVectors3( a, v[1], v[0] );
dSubtractVectors3( b, v[2], v[0] );
dCalcVectorCross3( n, b, a );
nx = fabs(n[0]);
ny = fabs(n[1]);
nz = fabs(n[2]);
if( nx > ny && nx > nz )
C = 0;
else
C = (ny > nz) ? 1 : 2;
// Even though all triangles might be initially valid,
// a triangle may degenerate into a segment after applying
// space transformation.
if (n[C] != REAL(0.0))
{
A = (C + 1) % 3;
B = (A + 1) % 3;
// calculate face integrals
{
dReal w;
dReal k1, k2, k3, k4;
//compProjectionIntegrals(f);
{
dReal a0=0, a1=0, da;
dReal b0=0, b1=0, db;
dReal a0_2, a0_3, a0_4, b0_2, b0_3, b0_4;
dReal a1_2, a1_3, b1_2, b1_3;
dReal C1, Ca, Caa, Caaa, Cb, Cbb, Cbbb;
dReal Cab, Kab, Caab, Kaab, Cabb, Kabb;
P1 = Pa = Pb = Paa = Pab = Pbb = Paaa = Paab = Pabb = Pbbb = 0.0;
for( int j = 0; j < 3; j++)
{
switch(j)
{
case 0:
a0 = v[0][A];
b0 = v[0][B];
a1 = v[1][A];
b1 = v[1][B];
break;
case 1:
a0 = v[1][A];
b0 = v[1][B];
a1 = v[2][A];
b1 = v[2][B];
break;
case 2:
a0 = v[2][A];
b0 = v[2][B];
a1 = v[0][A];
b1 = v[0][B];
break;
}
da = a1 - a0;
db = b1 - b0;
a0_2 = a0 * a0; a0_3 = a0_2 * a0; a0_4 = a0_3 * a0;
b0_2 = b0 * b0; b0_3 = b0_2 * b0; b0_4 = b0_3 * b0;
a1_2 = a1 * a1; a1_3 = a1_2 * a1;
b1_2 = b1 * b1; b1_3 = b1_2 * b1;
C1 = a1 + a0;
Ca = a1*C1 + a0_2; Caa = a1*Ca + a0_3; Caaa = a1*Caa + a0_4;
Cb = b1*(b1 + b0) + b0_2; Cbb = b1*Cb + b0_3; Cbbb = b1*Cbb + b0_4;
Cab = 3*a1_2 + 2*a1*a0 + a0_2; Kab = a1_2 + 2*a1*a0 + 3*a0_2;
Caab = a0*Cab + 4*a1_3; Kaab = a1*Kab + 4*a0_3;
Cabb = 4*b1_3 + 3*b1_2*b0 + 2*b1*b0_2 + b0_3;
Kabb = b1_3 + 2*b1_2*b0 + 3*b1*b0_2 + 4*b0_3;
P1 += db*C1;
Pa += db*Ca;
Paa += db*Caa;
Paaa += db*Caaa;
Pb += da*Cb;
Pbb += da*Cbb;
Pbbb += da*Cbbb;
Pab += db*(b1*Cab + b0*Kab);
Paab += db*(b1*Caab + b0*Kaab);
Pabb += da*(a1*Cabb + a0*Kabb);
}
P1 /= 2.0;
Pa /= 6.0;
Paa /= 12.0;
Paaa /= 20.0;
Pb /= -6.0;
Pbb /= -12.0;
Pbbb /= -20.0;
Pab /= 24.0;
Paab /= 60.0;
Pabb /= -60.0;
}
w = - dCalcVectorDot3(n, v[0]);
k1 = 1 / n[C]; k2 = k1 * k1; k3 = k2 * k1; k4 = k3 * k1;
Fa = k1 * Pa;
Fb = k1 * Pb;
Fc = -k2 * (n[A]*Pa + n[B]*Pb + w*P1);
Faa = k1 * Paa;
Fbb = k1 * Pbb;
Fcc = k3 * (SQR(n[A])*Paa + 2*n[A]*n[B]*Pab + SQR(n[B])*Pbb +
w*(2*(n[A]*Pa + n[B]*Pb) + w*P1));
Faaa = k1 * Paaa;
Fbbb = k1 * Pbbb;
Fccc = -k4 * (CUBE(n[A])*Paaa + 3*SQR(n[A])*n[B]*Paab
+ 3*n[A]*SQR(n[B])*Pabb + CUBE(n[B])*Pbbb
+ 3*w*(SQR(n[A])*Paa + 2*n[A]*n[B]*Pab + SQR(n[B])*Pbb)
+ w*w*(3*(n[A]*Pa + n[B]*Pb) + w*P1));
Faab = k1 * Paab;
Fbbc = -k2 * (n[A]*Pabb + n[B]*Pbbb + w*Pbb);
Fcca = k3 * (SQR(n[A])*Paaa + 2*n[A]*n[B]*Paab + SQR(n[B])*Pabb
+ w*(2*(n[A]*Paa + n[B]*Pab) + w*Pa));
}
T0 += n[0] * ((A == 0) ? Fa : ((B == 0) ? Fb : Fc));
T1[A] += n[A] * Faa;
T1[B] += n[B] * Fbb;
T1[C] += n[C] * Fcc;
T2[A] += n[A] * Faaa;
T2[B] += n[B] * Fbbb;
T2[C] += n[C] * Fccc;
TP[A] += n[A] * Faab;
TP[B] += n[B] * Fbbc;
TP[C] += n[C] * Fcca;
}
}
T1[0] /= 2; T1[1] /= 2; T1[2] /= 2;
T2[0] /= 3; T2[1] /= 3; T2[2] /= 3;
TP[0] /= 2; TP[1] /= 2; TP[2] /= 2;
m->mass = density * T0;
m->_I(0,0) = density * (T2[1] + T2[2]);
m->_I(1,1) = density * (T2[2] + T2[0]);
m->_I(2,2) = density * (T2[0] + T2[1]);
m->_I(0,1) = - density * TP[0];
m->_I(1,0) = - density * TP[0];
m->_I(2,1) = - density * TP[1];
m->_I(1,2) = - density * TP[1];
m->_I(2,0) = - density * TP[2];
m->_I(0,2) = - density * TP[2];
// Added to address SF bug 1729095
dMassTranslate( m, T1[0] / T0, T1[1] / T0, T1[2] / T0 );
# ifndef dNODEBUG
dMassCheck (m);
# endif
#endif // dTRIMESH_ENABLED
}
