dgInt32 dgCollisionConvexPolygon::CalculateContactToConvexHullContinue (dgCollisionParamProxy& proxy, const dgVector& polyInstanceScale, const dgVector& polyInstanceInvScale)
{
    dgAssert (proxy.m_referenceCollision->IsType (dgCollision::dgCollisionConvexShape_RTTI));
    dgAssert (proxy.m_floatingCollision->IsType (dgCollision::dgCollisionConvexPolygon_RTTI));

    const dgCollisionInstance* const hull = proxy.m_referenceCollision;

    dgAssert (this == proxy.m_floatingCollision->GetChildShape());
    dgAssert (m_count);
    dgAssert (m_count < dgInt32 (sizeof (m_localPoly) / sizeof (m_localPoly[0])));

    const dgBody* const floatingBody = proxy.m_floatingBody;
    const dgBody* const referenceBody = proxy.m_referenceBody;

    dgContact* const contactJoint = proxy.m_contactJoint;
    contactJoint->m_closestDistance = dgFloat32 (1.0e10f);

    m_normal = m_normal.CompProduct4(polyInstanceInvScale);
    dgAssert (m_normal.m_w == dgFloat32 (0.0f));
    m_normal = m_normal.CompProduct4(m_normal.DotProduct4(m_normal).InvSqrt());
    const dgVector savedFaceNormal (m_normal);

    for (dgInt32 i = 0; i < m_count; i ++) {
        m_localPoly[i] = polyInstanceScale.CompProduct4(dgVector (&m_vertex[m_vertexIndex[i] * m_stride]));
        dgAssert (m_localPoly[i].m_w == dgFloat32 (0.0f));
    }

    dgVector hullOrigin (proxy.m_matrix.UntransformVector(dgVector (dgFloat32 (0.0f))));
    hullOrigin = (hullOrigin - m_normal.CompProduct4(m_normal.DotProduct4(hullOrigin - m_localPoly[0]))) | dgVector::m_wOne;

    dgMatrix polygonMatrix;
    polygonMatrix[0] = m_localPoly[1] - m_localPoly[0];
    polygonMatrix[0] = polygonMatrix[0].CompProduct4 (polygonMatrix[0].InvMagSqrt());
    polygonMatrix[1] = m_normal;
    polygonMatrix[2] = polygonMatrix[0] * m_normal;
    polygonMatrix[3] = hullOrigin;
    dgAssert (polygonMatrix.TestOrthogonal());

    dgMatrix savedProxyMatrix (proxy.m_matrix);
    proxy.m_matrix = polygonMatrix * proxy.m_matrix;

    dgVector floatingVeloc (floatingBody->m_veloc);
    dgVector referenceVeloc (referenceBody->m_veloc);
    const dgMatrix& hullMatrix = hull->GetGlobalMatrix();
    dgVector hullRelativeVeloc (hullMatrix.UnrotateVector(referenceVeloc - floatingVeloc));
    dgVector polyRelativeVeloc (proxy.m_matrix.UnrotateVector (hullRelativeVeloc));

    dgVector polyBoxP0 (dgFloat32 ( 1.0e15f));
    dgVector polyBoxP1 (dgFloat32 (-1.0e15f));
    m_normal = polygonMatrix.UnrotateVector(m_normal);

    if (m_normal.DotProduct4(polyRelativeVeloc).m_x >= 0.0f) {
        proxy.m_matrix = savedProxyMatrix;
        return 0;
    }
    for (dgInt32 i = 0; i < m_count; i ++) {
        m_localPoly[i] = polygonMatrix.UntransformVector(m_localPoly[i]);
        dgAssert (m_localPoly[i].m_w == dgFloat32 (0.0f));
        polyBoxP0 = polyBoxP0.GetMin (m_localPoly[i]);
        polyBoxP1 = polyBoxP1.GetMax (m_localPoly[i]);
    }
    dgInt32 count = 0;


    dgVector hullBoxP0;
    dgVector hullBoxP1;
    hull->CalcAABB (proxy.m_matrix.Inverse(), hullBoxP0, hullBoxP1);
    dgVector minBox (polyBoxP0 - hullBoxP1);
    dgVector maxBox (polyBoxP1 - hullBoxP0);
    dgFastRayTest ray (dgVector (dgFloat32 (0.0f)), polyRelativeVeloc);
    dgFloat32 distance = ray.BoxIntersect(minBox, maxBox);

    if (distance < dgFloat32 (1.0f)) {

        dgVector boxSize ((hullBoxP1 - hullBoxP0).Scale4 (dgFloat32 (0.5f)));
//		dgVector boxOrigin ((hullBoxP1 + hullBoxP0).Scale4 (dgFloat32 (0.5f)));
//		boxOrigin += polyRelativeVeloc.Scale4 (distance);

        dgVector normalInHull (proxy.m_matrix.RotateVector (m_normal.Scale4 (dgFloat32 (-1.0f))));
        dgVector pointInHull (hull->SupportVertex (normalInHull, NULL));
        dgVector pointInPlane (proxy.m_matrix.UntransformVector (pointInHull));
        dgFloat32 distToPlane = (m_localPoly[0] - pointInPlane) % m_normal;
        dgFloat32 timeToPlane = distToPlane / (polyRelativeVeloc % m_normal);
        dgVector boxOrigin (pointInPlane + polyRelativeVeloc.Scale4(timeToPlane));

        bool inside = true;
        dgInt32 i0 = m_count - 1;
        for (dgInt32 i = 0; i < m_count; i ++) {
            dgVector e (m_localPoly[i] - m_localPoly[i0]);
            dgVector n (m_normal * e);
            dgPlane plane (n, - (m_localPoly[i0] % n));

            dgVector supportDist (plane.Abs().DotProduct4 (boxSize));
            dgFloat32 centerDist = plane.Evalue(boxOrigin);

            if ((centerDist + supportDist.m_x) < dgFloat32 (0.0f)) {
                proxy.m_matrix = savedProxyMatrix;
                return 0;
            }

            if ((centerDist - supportDist.m_x) < dgFloat32 (0.0f)) {
                inside = false;
            }
            i0 = i;
        }

// for the time being for the minkousky contact calculation
        inside = false;
        const dgInt32 hullId = hull->GetUserDataID();
        if (inside) {
            dgVector normalInHull (proxy.m_matrix.RotateVector (m_normal.Scale4 (dgFloat32 (-1.0f))));
            dgVector pointInHull (hull->SupportVertex (normalInHull, NULL));
            dgVector p0 (proxy.m_matrix.UntransformVector (pointInHull));

            dgFloat32 timetoImpact = dgFloat32 (0.0f);
            //dgFloat32 closestDistance = dgFloat32 (0.0f);
            dgAssert (0);
//			dgFloat32 penetration = (m_localPoly[0] - p0) % m_normal + proxy.m_skinThickness + DG_IMPULSIVE_CONTACT_PENETRATION;
            dgFloat32 penetration = (m_localPoly[0] - p0) % m_normal + proxy.m_skinThickness;
            if (penetration < dgFloat32 (0.0f)) {
                timetoImpact = penetration / (polyRelativeVeloc % m_normal);
                dgAssert (timetoImpact >= dgFloat32 (0.0f));
//				closestDistance = -penetration;
            }

            if (timetoImpact <= proxy.m_timestep) {
                dgVector pointsContacts[64];

                contactJoint->m_closestDistance = penetration;
                dgAssert (0);
//				dgVector point (pointInHull - normalInHull.Scale4(DG_IMPULSIVE_CONTACT_PENETRATION));
                dgVector point (pointInHull);

                count = hull->CalculatePlaneIntersection (normalInHull, point, pointsContacts, 1.0f);
                dgAssert (0);
//				dgVector step (hullRelativeVeloc.Scale3 (timetoImpact) + normalInHull.Scale4(DG_IMPULSIVE_CONTACT_PENETRATION));
                dgVector step (hullRelativeVeloc.Scale3 (timetoImpact));

                penetration = dgMax (penetration, dgFloat32 (0.0f));
                const dgMatrix& worldMatrix = hull->m_globalMatrix;
                dgContactPoint* const contactsOut = proxy.m_contacts;
                dgVector globalNormal (worldMatrix.RotateVector(normalInHull));
                for (dgInt32 i = 0; i < count; i ++) {
                    contactsOut[i].m_point = worldMatrix.TransformVector (pointsContacts[i] + step);
                    contactsOut[i].m_normal = globalNormal;
                    contactsOut[i].m_shapeId0 = hullId;
                    contactsOut[i].m_shapeId1 = m_faceId;
                    contactsOut[i].m_penetration = penetration;
                }
            }
        } else {
            dgFloat32 convexSphapeUmbra = hull->GetUmbraClipSize ();
            if (m_faceClipSize > convexSphapeUmbra) {
                BeamClipping (boxOrigin, convexSphapeUmbra);
                m_faceClipSize = hull->m_childShape->GetBoxMaxRadius();
            }

            dgCollisionConvex* const convexShape = (dgCollisionConvex*) hull->m_childShape;
            count = convexShape->CalculateConvexCastContacts (proxy);

//			dgAssert (proxy.m_intersectionTestOnly || (count >= 0));
            if (count >= 1) {
                dgContactPoint* const contactsOut = proxy.m_contacts;
#if 0
                if (m_closestFeatureType == 3) {
                    for (dgInt32 i = 0; i < count; i ++) {
                        contactsOut[i].m_shapeId0 = hullId;
                        contactsOut[i].m_shapeId1 = m_faceId;
                    }
                } else {
                    dgVector normal (polygonInstance->m_globalMatrix.UnrotateVector(contactsOut[0].m_normal));
                    if ((normal % savedFaceNormal) < dgFloat32 (0.995f)) {
                        dgInt32 index = m_adjacentFaceEdgeNormalIndex[m_closestFeatureStartIndex];
                        dgVector n (&m_vertex[index * m_stride]);
                        dgVector dir0 (n * savedFaceNormal);
                        dgVector dir1 (n * normal);
                        dgFloat32 projection = dir0 % dir1;
                        if (projection <= dgFloat32 (0.0f)) {
                            normal = n;
                        }
                        normal = polygonInstance->m_globalMatrix.RotateVector(normal);
                        for (dgInt32 i = 0; i < count; i ++) {
                            contactsOut[i].m_normal = normal;
                            //contactsOut[i].m_userId = m_faceId;
                            contactsOut[i].m_shapeId0 = hullId;
                            contactsOut[i].m_shapeId1 = m_faceId;
                        }
                    } else {
                        for (dgInt32 i = 0; i < count; i ++) {
                            //contactsOut[i].m_userId = m_faceId;
                            contactsOut[i].m_shapeId0 = hullId;
                            contactsOut[i].m_shapeId1 = m_faceId;
                        }
                    }
                }
#endif

                for (dgInt32 i = 0; i < count; i ++) {
                    contactsOut[i].m_shapeId0 = hullId;
                    contactsOut[i].m_shapeId1 = m_faceId;
                }
            }
        }
    }

    proxy.m_matrix = savedProxyMatrix;
    return count;
}
dgInt32 dgCollisionConvexPolygon::CalculateContactToConvexHullContinue(const dgWorld* const world, const dgCollisionInstance* const parentMesh, dgCollisionParamProxy& proxy)
{
	dgAssert(proxy.m_instance0->IsType(dgCollision::dgCollisionConvexShape_RTTI));
	dgAssert(proxy.m_instance1->IsType(dgCollision::dgCollisionConvexPolygon_RTTI));

	dgAssert(this == proxy.m_instance1->GetChildShape());
	dgAssert(m_count);
	dgAssert(m_count < dgInt32(sizeof (m_localPoly) / sizeof (m_localPoly[0])));

	const dgBody* const body0 = proxy.m_body0;
	const dgBody* const body1 = proxy.m_body1;

	dgAssert (proxy.m_instance1->GetGlobalMatrix().TestIdentity());

	dgVector relativeVelocity (body0->m_veloc - body1->m_veloc);
	if (m_normal.DotProduct4(relativeVelocity).GetScalar() >= 0.0f) {
		return 0;
	}
	dgFloat32 den = dgFloat32 (1.0f) / (relativeVelocity % m_normal);
	if (den > dgFloat32 (1.0e-5f)) {
		// this can actually happens
		dgAssert(0);
		return 0;
	}

	dgContact* const contactJoint = proxy.m_contactJoint;
	contactJoint->m_closestDistance = dgFloat32(1.0e10f);

	dgMatrix polygonMatrix;
	dgVector right (m_localPoly[1] - m_localPoly[0]);
	polygonMatrix[0] = right.CompProduct4(right.InvMagSqrt());
	polygonMatrix[1] = m_normal;
	polygonMatrix[2] = polygonMatrix[0] * m_normal;
	polygonMatrix[3] = dgVector::m_wOne;
	dgAssert (polygonMatrix.TestOrthogonal());

	dgVector polyBoxP0(dgFloat32(1.0e15f));
	dgVector polyBoxP1(dgFloat32(-1.0e15f));
	for (dgInt32 i = 0; i < m_count; i++) {
		dgVector point (polygonMatrix.UnrotateVector(m_localPoly[i]));
		polyBoxP0 = polyBoxP0.GetMin(point);
		polyBoxP1 = polyBoxP1.GetMax(point);
	}

	dgVector hullBoxP0;
	dgVector hullBoxP1;
	dgMatrix hullMatrix (polygonMatrix * proxy.m_instance0->m_globalMatrix);
	proxy.m_instance0->CalcAABB(hullMatrix, hullBoxP0, hullBoxP1);
	dgVector minBox(polyBoxP0 - hullBoxP1);
	dgVector maxBox(polyBoxP1 - hullBoxP0);
	dgVector veloc (polygonMatrix.UnrotateVector (relativeVelocity));
	dgFastRayTest ray(dgVector(dgFloat32(0.0f)), veloc);
 	dgFloat32 distance = ray.BoxIntersect(minBox, maxBox);

	dgInt32 count = 0;
	if (distance < dgFloat32(1.0f)) {
		bool inside = false;

		dgVector boxSize((hullBoxP1 - hullBoxP0).CompProduct4(dgVector::m_half));
		dgVector sphereMag2 (boxSize.DotProduct4(boxSize));
		boxSize = sphereMag2.Sqrt();

		dgVector pointInPlane (polygonMatrix.RotateVector(hullBoxP1 + hullBoxP0).CompProduct4(dgVector::m_half));
		dgFloat32 distToPlane = (m_localPoly[0] - pointInPlane) % m_normal;

		dgFloat32 timeToPlane0 = (distToPlane + boxSize.GetScalar()) * den;
		dgFloat32 timeToPlane1 = (distToPlane - boxSize.GetScalar()) * den;

		dgVector boxOrigin0 (pointInPlane + relativeVelocity.Scale4(timeToPlane0));
		dgVector boxOrigin1 (pointInPlane + relativeVelocity.Scale4(timeToPlane1));
		dgVector boxOrigin ((boxOrigin0 + boxOrigin1).CompProduct4(dgVector::m_half)); 
		dgVector boxProjectSize (((boxOrigin0 - boxOrigin1).CompProduct4(dgVector::m_half))); 
		sphereMag2 = boxProjectSize.DotProduct4(boxProjectSize);
		boxSize = sphereMag2.Sqrt();

		dgAssert (boxOrigin.m_w == 0.0f);
		boxOrigin = boxOrigin | dgVector::m_wOne;
		
		if (!proxy.m_intersectionTestOnly) {
			inside = true;
			dgInt32 i0 = m_count - 1;

			for (dgInt32 i = 0; i < m_count; i++) {
				dgVector e(m_localPoly[i] - m_localPoly[i0]);
				dgVector n(m_normal * e & dgVector::m_triplexMask);
				dgFloat32 param = dgSqrt (sphereMag2.GetScalar() / (n.DotProduct4(n)).GetScalar());
				dgPlane plane(n, -(m_localPoly[i0] % n));

				dgVector p0 (boxOrigin + n.Scale4 (param));
				dgVector p1 (boxOrigin - n.Scale4 (param));

				dgFloat32 size0 = (plane.DotProduct4 (p0)).GetScalar();
				dgFloat32 size1 = (plane.DotProduct4 (p1)).GetScalar();

				if ((size0 < 0.0f) && (size1 < 0.0f)) {
					return 0;
				}

				if ((size0 * size1) < 0.0f) {
					inside = false;
					break;
				}
				i0 = i;
			}
		}

		dgFloat32 convexSphapeUmbra = dgMax (proxy.m_instance0->GetUmbraClipSize(), boxSize.GetScalar());
		if (m_faceClipSize > convexSphapeUmbra) {
			BeamClipping(boxOrigin, convexSphapeUmbra);
			m_faceClipSize = proxy.m_instance0->m_childShape->GetBoxMaxRadius();
		}

		const dgInt32 hullId = proxy.m_instance0->GetUserDataID();
		if (inside & !proxy.m_intersectionTestOnly) {
			const dgMatrix& matrixInstance0 = proxy.m_instance0->m_globalMatrix;
			dgVector normalInHull(matrixInstance0.UnrotateVector(m_normal.Scale4(dgFloat32(-1.0f))));
			dgVector pointInHull(proxy.m_instance0->SupportVertex(normalInHull, NULL));
			dgVector p0 (matrixInstance0.TransformVector(pointInHull));

			dgFloat32 timetoImpact = dgFloat32(0.0f);
			dgFloat32 penetration = (m_localPoly[0] - p0) % m_normal + proxy.m_skinThickness;
			if (penetration < dgFloat32(0.0f)) {
				timetoImpact = penetration / (relativeVelocity % m_normal);
				dgAssert(timetoImpact >= dgFloat32(0.0f));
			}

			if (timetoImpact <= proxy.m_timestep) {
				dgVector contactPoints[64];
				contactJoint->m_closestDistance = penetration;
				proxy.m_timestep = timetoImpact;
				proxy.m_normal = m_normal;
				proxy.m_closestPointBody0 = p0;
				proxy.m_closestPointBody1 = p0 + m_normal.Scale4(penetration);

				if (!proxy.m_intersectionTestOnly) {
					pointInHull -= normalInHull.Scale4 (DG_ROBUST_PLANE_CLIP);
					count = proxy.m_instance0->CalculatePlaneIntersection(normalInHull, pointInHull, contactPoints);

					dgVector step(relativeVelocity.Scale4(timetoImpact));
					penetration = dgMax(penetration, dgFloat32(0.0f));
					dgContactPoint* const contactsOut = proxy.m_contacts;
					for (dgInt32 i = 0; i < count; i++) {
						contactsOut[i].m_point = matrixInstance0.TransformVector(contactPoints[i]) + step;
						contactsOut[i].m_normal = m_normal;
						contactsOut[i].m_shapeId0 = hullId;
						contactsOut[i].m_shapeId1 = m_faceId;
						contactsOut[i].m_penetration = penetration;
					}
				}
			}
		} else {
			m_vertexCount = dgUnsigned16 (m_count);
			count = world->CalculateConvexToConvexContacts(proxy);
			if (count >= 1) {
				dgContactPoint* const contactsOut = proxy.m_contacts;
				for (dgInt32 i = 0; i < count; i++) {
					contactsOut[i].m_shapeId0 = hullId;
					contactsOut[i].m_shapeId1 = m_faceId;
				}
			}
		}
	}

	return count;
}