/// Test if a point lies within a shape.
public static cpContactPointSet Collide(cpShape a, cpShape b, ref List <cpContact> contacts)
{
//cpContact[] contacts = new cpContact[cpArbiter.CP_MAX_CONTACTS_PER_ARBITER];
cpCollisionInfo info = cpCollision.cpCollide(a, b, 0, ref contacts);
cpContactPointSet set = new cpContactPointSet();
set.count = info.count;
set.points = new PointsDistance[set.count];
// cpCollideShapes() may have swapped the contact order. Flip the normal.
bool swapped = (a != info.a);
set.normal = (swapped ? cpVect.cpvneg(info.n) : info.n);
for (int i = 0; i < info.count; i++)
{
cpVect p1 = contacts[i].r1;
cpVect p2 = contacts[i].r2;
set.points[i] = new PointsDistance();
set.points[i].pointA = (swapped ? p2 : p1);
set.points[i].pointB = (swapped ? p1 : p2);
set.points[i].distance = cpVect.cpvdot(cpVect.cpvsub(p2, p1), set.normal);
}
return(set);
}
public void SetContactPointSet(ref cpContactPointSet set)
{
int count = set.count;
cp.AssertHard(count == Count, "The number of contact points cannot be changed.");
this.n = (this.swapped ? cpVect.cpvneg(set.normal) : set.normal);
for (int i = 0; i < count; i++)
{
// Convert back to CoG relative offsets.
cpVect p1 = set.points[i].pointA;
cpVect p2 = set.points[i].pointB;
this.contacts[i].r1 = cpVect.cpvsub(swapped ? p2 : p1, this.body_a.p);
this.contacts[i].r2 = cpVect.cpvsub(swapped ? p1 : p2, this.body_b.p);
}
}
public ulong ShapeQueryFunc(cpShape a, cpShape b, ulong id, ShapeQueryContext context)
{
if (cpShapeFilter.Reject(a.filter, b.filter) || a == b)
{
return(id);
}
List <cpContact> contacts = new List <cpContact>();
cpContactPointSet set = cpShape.Collide(a, b, ref contacts);
if (set.count > 0)
{
if (context.func != null)
{
context.func(b, set, context.data);
}
context.anyCollision = !(a.sensor || b.sensor);
}
return(id);
}
/// Return a contact set from an arbiter.
public cpContactPointSet GetContactPointSet()
{
cpContactPointSet set = new cpContactPointSet();
set.count = GetCount();
set.points = new PointsDistance[set.count];
bool swapped = this.swapped;
set.normal = (swapped ? cpVect.cpvneg(this.n) : this.n);
for (int i = 0; i < set.count; i++)
{
// Contact points are relative to body CoGs;
cpVect p1 = cpVect.cpvadd(this.body_a.p, this.contacts[i].r1);
cpVect p2 = cpVect.cpvadd(this.body_b.p, this.contacts[i].r2);
set.points[i] = new PointsDistance();
set.points[i].pointA = (swapped ? p2 : p1);
set.points[i].pointB = (swapped ? p1 : p2);
set.points[i].distance = cpVect.cpvdot(cpVect.cpvsub(p2, p1), this.n);
}
return(set);
}