// TODO_ERIN might not need to return the separation
public virtual float initialize(Distance.SimplexCache cache, Distance.DistanceProxy proxyA, Sweep sweepA, Distance.DistanceProxy proxyB, Sweep sweepB, float t1)
{
m_proxyA = proxyA;
m_proxyB = proxyB;
int count = cache.count;
Debug.Assert(0 < count && count < 3);
m_sweepA = sweepA;
m_sweepB = sweepB;
m_sweepA.getTransform(xfa, t1);
m_sweepB.getTransform(xfb, t1);
// log.debug("initializing separation.\n" +
// "cache: "+cache.count+"-"+cache.metric+"-"+cache.indexA+"-"+cache.indexB+"\n"
// "distance: "+proxyA.
if (count == 1)
{
m_type = Type.POINTS;
/*
* Vec2 localPointA = m_proxyA.GetVertex(cache.indexA[0]); Vec2 localPointB =
* m_proxyB.GetVertex(cache.indexB[0]); Vec2 pointA = Mul(transformA, localPointA); Vec2
* pointB = Mul(transformB, localPointB); m_axis = pointB - pointA; m_axis.Normalize();
*/
localPointA.set_Renamed(m_proxyA.getVertex(cache.indexA[0]));
localPointB.set_Renamed(m_proxyB.getVertex(cache.indexB[0]));
Transform.mulToOutUnsafe(xfa, localPointA, pointA);
Transform.mulToOutUnsafe(xfb, localPointB, pointB);
m_axis.set_Renamed(pointB).subLocal(pointA);
float s = m_axis.normalize();
return s;
}
else if (cache.indexA[0] == cache.indexA[1])
{
// Two points on B and one on A.
m_type = Type.FACE_B;
localPointB1.set_Renamed(m_proxyB.getVertex(cache.indexB[0]));
localPointB2.set_Renamed(m_proxyB.getVertex(cache.indexB[1]));
temp.set_Renamed(localPointB2).subLocal(localPointB1);
Vec2.crossToOutUnsafe(temp, 1f, m_axis);
m_axis.normalize();
Rot.mulToOutUnsafe(xfb.q, m_axis, normal);
m_localPoint.set_Renamed(localPointB1).addLocal(localPointB2).mulLocal(.5f);
Transform.mulToOutUnsafe(xfb, m_localPoint, pointB);
localPointA.set_Renamed(proxyA.getVertex(cache.indexA[0]));
Transform.mulToOutUnsafe(xfa, localPointA, pointA);
temp.set_Renamed(pointA).subLocal(pointB);
float s = Vec2.dot(temp, normal);
if (s < 0.0f)
{
m_axis.negateLocal();
s = -s;
}
return s;
}
else
{
// Two points on A and one or two points on B.
m_type = Type.FACE_A;
localPointA1.set_Renamed(m_proxyA.getVertex(cache.indexA[0]));
localPointA2.set_Renamed(m_proxyA.getVertex(cache.indexA[1]));
temp.set_Renamed(localPointA2).subLocal(localPointA1);
Vec2.crossToOutUnsafe(temp, 1.0f, m_axis);
m_axis.normalize();
Rot.mulToOutUnsafe(xfa.q, m_axis, normal);
m_localPoint.set_Renamed(localPointA1).addLocal(localPointA2).mulLocal(.5f);
Transform.mulToOutUnsafe(xfa, m_localPoint, pointA);
localPointB.set_Renamed(m_proxyB.getVertex(cache.indexB[0]));
Transform.mulToOutUnsafe(xfb, localPointB, pointB);
temp.set_Renamed(pointB).subLocal(pointA);
float s = Vec2.dot(temp, normal);
if (s < 0.0f)
{
m_axis.negateLocal();
s = -s;
}
return s;
}
}
