ofxBox2dJoint::ofxBox2dJoint(b2World* b2world, b2Body* body1, b2Body* body2, ofVec2f anchor1, ofVec2f anchor2, float frequencyHz, float damping, bool bCollideConnected) {
ofxBox2dJoint();
setup(b2world, body1, body2, anchor1, anchor2, frequencyHz, damping, bCollideConnected);
}
void Blobs02 :: addBlob( float bx, float by, float radius, int nodesTotal )
{
if( nodesTotal % 2 != 0 ) // always even number of nodes, for opposite joins to balance.
nodesTotal += 1;
blobs.push_back( Blob() );
float nodeMass;
float nodeBounce;
float nodeFriction;
nodeMass = 30.0;
nodeBounce = 0.53;
nodeFriction = 0.1;
blobs.back().nodesTotal = nodesTotal;
blobs.back().nodeRadius = radius;
blobs.back().nodeScale = new float[ nodesTotal ];
for( int i=0; i<nodesTotal; i++ )
{
blobs.back().nodeScale[ i ] = 0;
}
blobs.back().nodes.push_back( ofxBox2dCircle() ); // center node.
blobs.back().nodes.back().setPhysics( nodeMass, nodeBounce, nodeFriction );
blobs.back().nodes.back().setup( box2d.getWorld(), bx, by, 10, true );
blobs.back().nodes.back().disableCollistion();
// the joints
for( int i=0; i<nodesTotal; i++ )
{
float p = ( i / (float)nodesTotal ) * PI * 2;
float x = bx + cos( p ) * radius;
float y = by + sin( p ) * radius;
blobs.back().nodes.push_back( ofxBox2dCircle() );
blobs.back().nodes.back().setPhysics( nodeMass, nodeBounce, nodeFriction );
blobs.back().nodes.back().setup( box2d.getWorld(), x, y, 20 );
}
float jointStiffness; // joint stiffness.
float jointDamping; // joint damping.
jointStiffness = 10.0;
jointDamping = 0.9;
// joins between neighbouring nodes.
for( int i=1; i<blobs.back().nodes.size(); i++ )
{
blobs.back().nodeJoints.push_back( ofxBox2dJoint() );
if( i < blobs.back().nodes.size() - 1 )
{
blobs.back().nodeJoints.back().setWorld( box2d.getWorld() );
blobs.back().nodeJoints.back().addJoint( blobs.back().nodes[ i ].body, blobs.back().nodes[ i + 1 ].body, jointStiffness, jointDamping );
}
else
{
blobs.back().nodeJoints.back().setWorld( box2d.getWorld() );
blobs.back().nodeJoints.back().addJoint( blobs.back().nodes[ i ].body, blobs.back().nodes[ 1 ].body, jointStiffness, jointDamping );
}
}
jointStiffness = 1.0;
jointDamping = 0.9;
// joins between opposite nodes.
int nodesHalf = (int)( blobs.back().nodes.size() * 0.5 );
for( int i=1; i<nodesHalf + 1; i++ )
{
int j = i + nodesHalf;
blobs.back().nodeJoints.push_back( ofxBox2dJoint() );
blobs.back().nodeJoints.back().setWorld( box2d.getWorld() );
blobs.back().nodeJoints.back().addJoint( blobs.back().nodes[ i ].body, blobs.back().nodes[ j ].body, jointStiffness, jointDamping );
}
jointStiffness = 1.0;
jointDamping = 0.9;
// joins to center node.
for( int i=1; i<blobs.back().nodes.size(); i++ )
{
blobs.back().nodeJoints.push_back( ofxBox2dJoint() );
blobs.back().nodeJoints.back().setWorld( box2d.getWorld() );
blobs.back().nodeJoints.back().addJoint( blobs.back().nodes[ 0 ].body, blobs.back().nodes[ i ].body, jointStiffness, jointDamping );
}
}
//----------------------------------------
ofxBox2dJoint::ofxBox2dJoint(b2World* b2world, b2DistanceJointDef jointDef) {
ofxBox2dJoint();
setup(b2world, jointDef);
}
