# constraint context
# ------------------
b2.imass:scalar -> 0
anchor2:vector -> vec(0,0)
b2.iinertia:scalar -> 0
anchor1:vector -> vec(0,0)
b1.rot:scalar -> var(b1.angvel)
b1.pos:vector -> var(b1.vel)
b2.vel:vector -> vec(0,0)
b1.imass:scalar -> 0
b1.iinertia:scalar -> 0
b2.angvel:scalar -> 0
b1.vel:vector -> vec(0,0)
phase:scalar -> 0
b2.rot:scalar -> var(b2.angvel)
b1.angvel:scalar -> 0
b2.pos:vector -> var(b2.vel)


# positional constraint
# ---------------------
{((rel(b2.rot of var(anchor2))+var(b2.pos))+(-1*(rel(b1.rot of var(anchor1))+var(b1.pos))))
((var(b2.rot)+(-1*var(b1.rot)))+(-1*var(phase)))}

# velocity constraint
# -------------------
{(((var(b2.angvel)*perp(var(anchor2)))+var(b2.vel))+(-1*((var(b1.angvel)*perp(var(anchor1)))+var(b1.vel))))
(var(b2.angvel)+(-1*var(b1.angvel)))}
# jacobians
# ---------
{vec(-1,0)
0}

{vec(0,-1)
0}

{(-1*perp(var(anchor1)))
-1}

{vec(1,0)
0}

{vec(0,1)
0}

{perp(var(anchor2))
1}


# effective-mass matrix
# ---------------------
{{((((((var(b1.imass)*mat(1,0,0,0))+(var(b1.imass)*mat(0,0,0,1)))+(var(b1.iinertia)*outer((-1*perp(var(anchor1))),(-1*perp(var(anchor1))))))+(var(b2.imass)*mat(1,0,0,0)))+(var(b2.imass)*mat(0,0,0,1)))+(var(b2.iinertia)*outer(perp(var(anchor2)),perp(var(anchor2)))))
((var(b1.iinertia)*outer((-1*perp(var(anchor1))),-1))+(var(b2.iinertia)*outer(perp(var(anchor2)),1)))}
{((var(b1.iinertia)*outer(-1,(-1*perp(var(anchor1)))))+(var(b2.iinertia)*outer(1,perp(var(anchor2)))))
(var(b1.iinertia)+var(b2.iinertia))}}