/// <summary>
/// Initializes a new instance of the HingeJoint class.
/// </summary>
/// <param name="world">The world class where the constraints get added to.</param>
/// <param name="body1">The first body connected to the second one.</param>
/// <param name="body2">The second body connected to the first one.</param>
/// <param name="position">The position in world space where both bodies get connected.</param>
/// <param name="hingeAxis">The axis if the hinge.</param>
public LimitedHingeJoint(World world, RigidBody body1, RigidBody body2, JVector position, JVector hingeAxis,
float hingeFwdAngle, float hingeBckAngle)
: base(world)
{
// Create the hinge first, two point constraints
worldPointConstraint = new PointOnPoint[2];
hingeAxis *= 0.5f;
JVector pos1 = position; JVector.Add(ref pos1, ref hingeAxis, out pos1);
JVector pos2 = position; JVector.Subtract(ref pos2, ref hingeAxis, out pos2);
worldPointConstraint[0] = new PointOnPoint(body1, body2, pos1);
worldPointConstraint[1] = new PointOnPoint(body1, body2, pos2);
// Now the limit, one max distance constraint
hingeAxis.Normalize();
// choose a direction that is perpendicular to the hinge
JVector perpDir = JVector.Up;
if (JVector.Dot(perpDir, hingeAxis) > 0.1f) perpDir = JVector.Right;
// now make it perpendicular to the hinge
JVector sideAxis = JVector.Cross(hingeAxis, perpDir);
perpDir = JVector.Cross(sideAxis, hingeAxis);
perpDir.Normalize();
// the length of the "arm" TODO take this as a parameter? what's
// the effect of changing it?
float len = 10.0f * 3;
// Choose a position using that dir. this will be the anchor point
// for body 0. relative to hinge
JVector hingeRelAnchorPos0 = perpDir * len;
// anchor point for body 2 is chosen to be in the middle of the
// angle range. relative to hinge
float angleToMiddle = 0.5f * (hingeFwdAngle - hingeBckAngle);
JVector hingeRelAnchorPos1 = JVector.Transform(hingeRelAnchorPos0, JMatrix.CreateFromAxisAngle(hingeAxis, -angleToMiddle / 360.0f * 2.0f * JMath.Pi));
// work out the "string" length
float hingeHalfAngle = 0.5f * (hingeFwdAngle + hingeBckAngle);
float allowedDistance = len * 2.0f * (float)System.Math.Sin(hingeHalfAngle * 0.5f / 360.0f * 2.0f * JMath.Pi);
JVector hingePos = body1.Position;
JVector relPos0c = hingePos + hingeRelAnchorPos0;
JVector relPos1c = hingePos + hingeRelAnchorPos1;
distance = new PointPointDistance(body1, body2, relPos0c, relPos1c);
distance.Distance = allowedDistance;
distance.Behavior = PointPointDistance.DistanceBehavior.LimitMaximumDistance;
}
public PrismaticJoint(World world, RigidBody body1, RigidBody body2,float minimumDistance, float maximumDistance)
: base(world)
{
fixedAngle = new FixedAngle(body1, body2);
pointOnLine = new PointOnLine(body1, body2, body1.position, body2.position);
minDistance = new PointPointDistance(body1, body2, body1.position, body2.position);
minDistance.Behavior = PointPointDistance.DistanceBehavior.LimitMinimumDistance;
minDistance.Distance = minimumDistance;
maxDistance = new PointPointDistance(body1, body2, body1.position, body2.position);
maxDistance.Behavior = PointPointDistance.DistanceBehavior.LimitMaximumDistance;
maxDistance.Distance = maximumDistance;
}
private void CreatePointPointDistanceJoint()
{
JVector anchor1;
Vector3D tempVector = ArrayExtensions.GetWithDefault<PropertyType, Vector3D>(Properties,
PropertyType.Anchor1);
JitterDatatypesMapping.Convert(ref tempVector, out anchor1);
JVector anchor2;
tempVector = ArrayExtensions.GetWithDefault<PropertyType, Vector3D>(Properties,
PropertyType.Anchor2);
JitterDatatypesMapping.Convert(ref tempVector, out anchor2);
Constraint = new PointPointDistance(RigidBodyA, RigidBodyB, anchor1, anchor2);
}
public void BuildRagdoll(World world, JVector position)
{
// the torso
RigidBody torso = new RigidBody(new BoxShape(1.5f, 3, 0.5f));
torso.Position = position;
// the head
RigidBody head = new RigidBody(new SphereShape(0.5f));
head.Position = position + new JVector(0, 2.1f, 0);
// connect head and torso
PointPointDistance headTorso = new PointPointDistance(head, torso,
position + new JVector(0, 1.6f, 0), position + new JVector(0, 1.5f, 0));
RigidBody arm1 = new RigidBody(new CapsuleShape(0.8f, 0.2f));
arm1.Position = position + new JVector(1.0f, 0.75f, 0);
RigidBody arm2 = new RigidBody(new CapsuleShape(0.8f, 0.2f));
arm2.Position = position + new JVector(-1.0f, 0.75f, 0);
RigidBody lowerarm1 = new RigidBody(new CapsuleShape(0.6f, 0.2f));
lowerarm1.Position = position + new JVector(1.0f, -0.45f, 0);
RigidBody lowerarm2 = new RigidBody(new CapsuleShape(0.6f, 0.2f));
lowerarm2.Position = position + new JVector(-1.0f, -0.45f, 0);
PointOnPoint arm1torso = new PointOnPoint(arm1, torso, position + new JVector(0.9f, 1.4f, 0));
PointOnPoint arm2torso = new PointOnPoint(arm2, torso, position + new JVector(-0.9f, 1.4f, 0));
HingeJoint arm1Hinge = new HingeJoint(world, arm1, lowerarm1, position + new JVector(1.0f, 0.05f, 0), JVector.Right);
HingeJoint arm2Hinge = new HingeJoint(world, arm2, lowerarm2, position + new JVector(-1.0f, 0.05f, 0), JVector.Right);
RigidBody leg1 = new RigidBody(new CapsuleShape(1.0f, 0.3f));
leg1.Position = position + new JVector(-0.5f, -2.4f, 0);
RigidBody leg2 = new RigidBody(new CapsuleShape(1.0f, 0.3f));
leg2.Position = position + new JVector(0.5f, -2.4f, 0);
PointOnPoint leg1torso = new PointOnPoint(leg1, torso, position + new JVector(-0.5f, -1.6f, 0));
PointOnPoint leg2torso = new PointOnPoint(leg2, torso, position + new JVector(+0.5f, -1.6f, 0));
RigidBody lowerleg1 = new RigidBody(new CapsuleShape(0.8f, 0.3f));
lowerleg1.Position = position + new JVector(-0.5f, -4.0f, 0);
RigidBody lowerleg2 = new RigidBody(new CapsuleShape(0.8f, 0.3f));
lowerleg2.Position = position + new JVector(+0.5f, -4.0f, 0);
HingeJoint leg1Hinge = new HingeJoint(world, leg1, lowerleg1, position + new JVector(-0.5f, -3.35f, 0), JVector.Right);
HingeJoint leg2Hinge = new HingeJoint(world, leg2, lowerleg2, position + new JVector(0.5f, -3.35f, 0), JVector.Right);
lowerleg1.IsActive = false;
lowerleg2.IsActive = false;
leg1.IsActive = false;
leg2.IsActive = false;
head.IsActive = false;
torso.IsActive = false;
arm1.IsActive = false;
arm2.IsActive = false;
lowerarm1.IsActive = false;
lowerarm2.IsActive = false;
world.AddBody(head); world.AddBody(torso);
world.AddBody(arm1); world.AddBody(arm2);
world.AddBody(lowerarm1); world.AddBody(lowerarm2);
world.AddBody(leg1); world.AddBody(leg2);
world.AddBody(lowerleg1); world.AddBody(lowerleg2);
arm1Hinge.Activate(); arm2Hinge.Activate();
leg1Hinge.Activate(); leg2Hinge.Activate();
world.AddConstraint(headTorso);
world.AddConstraint(arm1torso);
world.AddConstraint(arm2torso);
world.AddConstraint(leg1torso);
world.AddConstraint(leg2torso);
}
