[ODE] AMD x86_64 dMassCheck() and bNormalizationResult errors

[Funky Fred]

Hello,
  using code that worked on x86_32, 
    dMass dmass;
    dMassSetZero( &dmass );
    //dMassAdjust( &dmass, mass );
    dmass.mass = mass;
    dBodySetMass( bodies[name], &dmass );
    return true;
gives me (on x86_64 - AMD):
(more code further down)

Starting program: /home/stu/evolve/physicsEngine/testPhysicsEngine 
[Thread debugging using libthread_db enabled]
[New Thread 47826867859296 (LWP 8997)]
gravity: 0,10,0

ODE Message 2: inertia must be positive definite in dMassCheck() File mass.cpp Line 48

ODE INTERNAL ERROR 1: assertion "dMassCheck(mass)" failed in dBodySetMass() [ode.cpp]

Program received signal SIGABRT, Aborted.
[Switching to Thread 47826867859296 (LWP 8997)]
0x00002b7f8f23d765 in raise () from /lib/libc.so.6
(gdb)  bt
#0  0x00002b7f8f23d765 in raise () from /lib/libc.so.6
#1  0x00002b7f8f23f1c0 in abort () from /lib/libc.so.6
#2  0x00002b7f8e7a38f6 in dDebug (num=, 
    msg=) at error.cpp:102
#3  0x00002b7f8e7a1ec9 in dBodySetMass (b=0x60e450, mass=0x7fff1c548680)
    at ode.cpp:472
#4  0x000000000040614f in evolve::PhysicsEngine::setMass (
    this=, name=@0x7fff1c548930, mass=10)
    at PhysicsEngine.cc:174
#5  0x00000000004095d3 in main () at testPhysicsEngine.cc:25
(gdb) 

If I change to 
    dMass dmass;
    dMassSetZero( &dmass );
    dMassAdjust( &dmass, mass );
    //dmass.mass = mass;
    dBodySetMass( bodies[name], &dmass );
    return true;

gravity: 0,10,0
before: 
pos 1: 0,10,0
pos 2: 0,10,0

ODE INTERNAL ERROR 1: assertion "bNormalizationResult" failed in _dNormalize4() [../../include/ode/odemath.h]

Program received signal SIGABRT, Aborted.
[Switching to Thread 47280432254816 (LWP 8903)]
0x00002b00550a3765 in raise () from /lib/libc.so.6
(gdb) bt
#0  0x00002b00550a3765 in raise () from /lib/libc.so.6
#1  0x00002b00550a51c0 in abort () from /lib/libc.so.6
#2  0x00002b00546098f6 in dDebug (num=, 
    msg=) at error.cpp:102
#3  0x00002b005464283a in dxStepBody (b=0x60e680, h=4.59163468e-41)
    at ../../include/ode/odemath.h:304
#4  0x00002b0054610a6f in dxQuickStepper (world=0x60e010, body=0x7fff566e2830, 
    nb=2, _joint=, nj=1, stepsize=1) at quickstep.cpp:868
#5  0x00002b00546422cd in dxProcessIslands (world=0x60e010, stepsize=1, 
    stepper=0x2b005460f630 ) at util.cpp:339
#6  0x00000000004042fe in evolve::PhysicsEngine::doPhysics (
    this=0x7fff566e2920) at PhysicsEngine.cc:240
#7  0x0000000000409920 in main () at testPhysicsEngine.cc:37


I'm using a test program that calls a C++ wrapper class. Relevant snippets are:
testPhysicsEngine.cc
...
    PhysicsEngine pe;
    vector grav = Utility::makeVector( 0.0, 10.0, 0.0 );
    pe.setGravity( grav[0], grav[1], grav[2] );
    grav.clear();
    pe.getGravity( grav );
    cout << "gravity: " << Utility::vectorToString( grav ) << endl;
    vector pos = Utility::makeVector( 0.0, 10.0, 0.0 );
    vector pos2 = Utility::makeVector( 0.0, 10.0, 0.0 );
    vector newpos1;
    vector newpos2;
    pe.addItem( "test1", pos, 5 );
    pe.addItem( "test2", pos2, 2 );
    pe.setMass( "test1", 10.0 );
    pe.setMass( "test2", 5.1 );


    cout << "before: " << endl;
    pe.getPosition( "test1", newpos1 );
    pe.getPosition( "test2", newpos2 );
    cout << "pos 1: " << Utility::vectorToString( newpos1 ) << endl;
    cout << "pos 2: " << Utility::vectorToString( newpos2 ) << endl;
    vector vel = Utility::makeVector( 0.0, -3.0, 0.0 );
    pe.setLinearVelocity( "test2", vel ); 
    for( int i = 0; i < 5; ++i )
        pe.doPhysics();
...

PhysicsEngine.cc
...
PhysicsEngine::PhysicsEngine()
{
    this->worldId = dWorldCreate();
    this->spaceId = dHashSpaceCreate( 0 );
    this->contactJointGroup = dJointGroupCreate( 0 );
    dWorldSetGravity( this->worldId, 0, 0, 0 );
}

bool PhysicsEngine::addItem( const string& name, const vector& pos, double radius )
{
   ...
    dGeomID geometry = dCreateSphere( this->spaceId, radius );
    dBodyID body = dBodyCreate(this->worldId);
    dGeomSetBody( geometry, body );
    dBodySetPosition( body, pos[0], pos[1], pos[2] );
    bodies[name] = body;
    return true;
}

bool PhysicsEngine::setMass( const string& name, double mass )
{
    ...
    dMass dmass;
    dMassSetZero( &dmass );
    //dMassAdjust( &dmass, mass );
    dmass.mass = mass;
    dBodySetMass( bodies[name], &dmass );
    return true;

}

bool PhysicsEngine::doPhysics()
{
    dSpaceCollide( this->spaceId, this, &nearCollisionCallback );
    dWorldQuickStep( this->worldId, 1 );
    dJointGroupEmpty( this->contactJointGroup );
    return true;
}

/*
 * callback for ODE. friend of PhysicsEngine. _this is meant to be 
 * a this pointer at the PhysicsEngine object currently using the callback.
 */
void evolve::nearCollisionCallback( void* _this, dGeomID id1, dGeomID id2 )
{
    dBodyID b1 = dGeomGetBody( id1 );
    dBodyID b2 = dGeomGetBody( id2 );

    //if( b1 && b2 && dAreConnectedExcluding( b1, b2, dJointTypeContact ) )
    //    return;

    short max_contacts = 10;
    dContact contacts[10]; //delete ?
    for( int i = 0; i < 10; ++i )
    {
        contacts[i].surface.mode = dContactBounce | dContactSoftCFM;
        contacts[i].surface.mu = dInfinity;
        contacts[i].surface.mu2 = 0;
        contacts[i].surface.bounce = 0.8;
        contacts[i].surface.bounce_vel = 0.1f;
        contacts[i].surface.soft_cfm = 0.01f;
    }
    int num_contacts = 0;
    num_contacts = dCollide( id1, id2, (unsigned int)max_contacts, &contacts[0].geom, sizeof(dContact) );
    for( int i = 0; i < num_contacts; ++i )
    {
        dJointID c = dJointCreateContact( ((PhysicsEngine*)_this)->worldId, ((PhysicsEngine*)_this)->contactJointGroup, &contacts[i] );
        dJointAttach( c, b1, b2 );
    }
}

Hope this all makes sense, any help would be appreciated. I tried digging into the ODE source files, but didn't make much progress. I gotta sleep now.

cheers,
  -Stu

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