void VehicleBody::_update_wheel(int p_idx, PhysicsDirectBodyState *s) {
VehicleWheel &wheel = *wheels[p_idx];
_update_wheel_transform(wheel, s);
Vector3 up = -wheel.m_raycastInfo.m_wheelDirectionWS;
const Vector3 &right = wheel.m_raycastInfo.m_wheelAxleWS;
Vector3 fwd = up.cross(right);
fwd = fwd.normalized();
//rotate around steering over de wheelAxleWS
real_t steering = wheel.steers ? m_steeringValue : 0.0;
Basis steeringMat(up, steering);
Basis rotatingMat(right, wheel.m_rotation);
Basis basis2(
right[0], up[0], fwd[0],
right[1], up[1], fwd[1],
right[2], up[2], fwd[2]);
wheel.m_worldTransform.set_basis(steeringMat * rotatingMat * basis2);
//wheel.m_worldTransform.set_basis(basis2 * (steeringMat * rotatingMat));
wheel.m_worldTransform.set_origin(
wheel.m_raycastInfo.m_hardPointWS + wheel.m_raycastInfo.m_wheelDirectionWS * wheel.m_raycastInfo.m_suspensionLength);
}
real_t VehicleBody::_ray_cast(int p_idx,PhysicsDirectBodyState *s) {
VehicleWheel& wheel = *wheels[p_idx];
_update_wheel_transform(wheel,s);
real_t depth = -1;
real_t raylen = wheel.m_suspensionRestLength+wheel.m_wheelRadius;
Vector3 rayvector = wheel.m_raycastInfo.m_wheelDirectionWS * (raylen);
Vector3 source = wheel.m_raycastInfo.m_hardPointWS;
wheel.m_raycastInfo.m_contactPointWS = source + rayvector;
const Vector3& target = wheel.m_raycastInfo.m_contactPointWS;
source-=wheel.m_wheelRadius * wheel.m_raycastInfo.m_wheelDirectionWS;
real_t param = real_t(0.);
PhysicsDirectSpaceState::RayResult rr;
PhysicsDirectSpaceState *ss=s->get_space_state();
bool col = ss->intersect_ray(source,target,rr,exclude);
wheel.m_raycastInfo.m_groundObject = 0;
if (col)
{
//print_line("WHEEL "+itos(p_idx)+" FROM "+source+" TO: "+target);
//print_line("WHEEL "+itos(p_idx)+" COLLIDE? "+itos(col));
param = source.distance_to(rr.position)/source.distance_to(target);
depth = raylen * param;
wheel.m_raycastInfo.m_contactNormalWS = rr.normal;
wheel.m_raycastInfo.m_isInContact = true;
if (rr.collider)
wheel.m_raycastInfo.m_groundObject=rr.collider->cast_to<PhysicsBody>();
real_t hitDistance = param*raylen;
wheel.m_raycastInfo.m_suspensionLength = hitDistance - wheel.m_wheelRadius;
//clamp on max suspension travel
real_t minSuspensionLength = wheel.m_suspensionRestLength - wheel.m_maxSuspensionTravelCm*real_t(0.01);
real_t maxSuspensionLength = wheel.m_suspensionRestLength+ wheel.m_maxSuspensionTravelCm*real_t(0.01);
if (wheel.m_raycastInfo.m_suspensionLength < minSuspensionLength)
{
wheel.m_raycastInfo.m_suspensionLength = minSuspensionLength;
}
if (wheel.m_raycastInfo.m_suspensionLength > maxSuspensionLength)
{
wheel.m_raycastInfo.m_suspensionLength = maxSuspensionLength;
}
wheel.m_raycastInfo.m_contactPointWS = rr.position;
real_t denominator= wheel.m_raycastInfo.m_contactNormalWS.dot( wheel.m_raycastInfo.m_wheelDirectionWS );
Vector3 chassis_velocity_at_contactPoint;
//Vector3 relpos = wheel.m_raycastInfo.m_contactPointWS-getRigidBody()->getCenterOfMassPosition();
//chassis_velocity_at_contactPoint = getRigidBody()->getVelocityInLocalPoint(relpos);
chassis_velocity_at_contactPoint = s->get_linear_velocity() +
(s->get_angular_velocity()).cross(wheel.m_raycastInfo.m_contactPointWS-s->get_transform().origin);// * mPos);
real_t projVel = wheel.m_raycastInfo.m_contactNormalWS.dot( chassis_velocity_at_contactPoint );
if ( denominator >= real_t(-0.1))
{
wheel.m_suspensionRelativeVelocity = real_t(0.0);
wheel.m_clippedInvContactDotSuspension = real_t(1.0) / real_t(0.1);
}
else
{
real_t inv = real_t(-1.) / denominator;
wheel.m_suspensionRelativeVelocity = projVel * inv;
wheel.m_clippedInvContactDotSuspension = inv;
}
} else
{
wheel.m_raycastInfo.m_isInContact = false;
//put wheel info as in rest position
wheel.m_raycastInfo.m_suspensionLength = wheel.m_suspensionRestLength;
wheel.m_suspensionRelativeVelocity = real_t(0.0);
wheel.m_raycastInfo.m_contactNormalWS = - wheel.m_raycastInfo.m_wheelDirectionWS;
wheel.m_clippedInvContactDotSuspension = real_t(1.0);
}
return depth;
}
