// Submitted by LegoCyclon
static int
seg2seg(const cpShape* shape1, const cpShape* shape2, cpContact* con)
{
cpSegmentShape* seg1 = (cpSegmentShape *)shape1;
cpSegmentShape* seg2 = (cpSegmentShape *)shape2;
cpVect v1 = cpvsub(seg1->tb, seg1->ta);
cpVect v2 = cpvsub(seg2->tb, seg2->ta);
cpFloat v1lsq = cpvlengthsq(v1);
cpFloat v2lsq = cpvlengthsq(v2);
// project seg2 onto seg1
cpVect p1a = cpvproject(cpvsub(seg2->ta, seg1->ta), v1);
cpVect p1b = cpvproject(cpvsub(seg2->tb, seg1->ta), v1);
// project seg1 onto seg2
cpVect p2a = cpvproject(cpvsub(seg1->ta, seg2->ta), v2);
cpVect p2b = cpvproject(cpvsub(seg1->tb, seg2->ta), v2);
// clamp projections to segment endcaps
if (cpvdot(p1a, v1) < 0.0f)
p1a = cpvzero;
else if (cpvdot(p1a, v1) > 0.0f && cpvlengthsq(p1a) > v1lsq)
p1a = v1;
if (cpvdot(p1b, v1) < 0.0f)
p1b = cpvzero;
else if (cpvdot(p1b, v1) > 0.0f && cpvlengthsq(p1b) > v1lsq)
p1b = v1;
if (cpvdot(p2a, v2) < 0.0f)
p2a = cpvzero;
else if (cpvdot(p2a, v2) > 0.0f && cpvlengthsq(p2a) > v2lsq)
p2a = v2;
if (cpvdot(p2b, v2) < 0.0f)
p2b = cpvzero;
else if (cpvdot(p2b, v2) > 0.0f && cpvlengthsq(p2b) > v2lsq)
p2b = v2;
p1a = cpvadd(p1a, seg1->ta);
p1b = cpvadd(p1b, seg1->ta);
p2a = cpvadd(p2a, seg2->ta);
p2b = cpvadd(p2b, seg2->ta);
int num = 0;
if (!circle2circleQuery(p1a, p2a, seg1->r, seg2->r, nextContactPoint(con, &num)))
--num;
if (!circle2circleQuery(p1b, p2b, seg1->r, seg2->r, nextContactPoint(con, &num)))
--num;
if (!circle2circleQuery(p1a, p2b, seg1->r, seg2->r, nextContactPoint(con, &num)))
--num;
if (!circle2circleQuery(p1b, p2a, seg1->r, seg2->r, nextContactPoint(con, &num)))
--num;
return num;
}
static inline cpVect
grooveConstrain(cpGrooveJoint *joint, cpVect j, cpFloat dt){
cpVect n = joint->grv_tn;
cpVect jClamp = (joint->clamp*cpvcross(j, n) > 0.0f) ? j : cpvproject(j, n);
return cpvclamp(jClamp, joint->constraint.maxForce*dt);
}
static inline cpVect
grooveConstrain(cpGrooveJoint *joint, cpVect j){
cpVect n = joint->grv_tn;
cpVect jClamp = (joint->clamp*cpvcross(j, n) > 0.0f) ? j : cpvproject(j, n);
return cpvclamp(jClamp, joint->jMaxLen);
}
cpVect * bmx_cpvect_project(cpVect * vec, cpVect * vec1) {
return bmx_cpvect_new(cpvproject(*vec, *vec1));
}
