/// <summary>
/// Cleans up the pair tester.
/// </summary>
public override void CleanUp()
{
sphere = null;
Updated = false;
}
///<summary>
/// Tests if a box and sphere are colliding.
///</summary>
///<param name="box">Box to test.</param>
///<param name="sphere">Sphere to test.</param>
///<param name="boxTransform">Transform to apply to the box.</param>
///<param name="spherePosition">Transform to apply to the sphere.</param>
///<param name="contact">Contact point between the shapes, if any.</param>
///<returns>Whether or not the shapes were colliding.</returns>
public static bool AreShapesColliding(BoxShape box, SphereShape sphere, ref RigidTransform boxTransform, ref Vector3 spherePosition, out ContactData contact)
{
contact = new ContactData();
Vector3 localPosition;
RigidTransform.TransformByInverse(ref spherePosition, ref boxTransform, out localPosition);
#if !WINDOWS
Vector3 localClosestPoint = new Vector3();
#else
Vector3 localClosestPoint;
#endif
localClosestPoint.X = MathHelper.Clamp(localPosition.X, -box.halfWidth, box.halfWidth);
localClosestPoint.Y = MathHelper.Clamp(localPosition.Y, -box.halfHeight, box.halfHeight);
localClosestPoint.Z = MathHelper.Clamp(localPosition.Z, -box.halfLength, box.halfLength);
RigidTransform.Transform(ref localClosestPoint, ref boxTransform, out contact.Position);
Vector3 offset;
Vector3.Subtract(ref spherePosition, ref contact.Position, out offset);
float offsetLength = offset.LengthSquared();
if (offsetLength > (sphere.collisionMargin + CollisionDetectionSettings.maximumContactDistance) * (sphere.collisionMargin + CollisionDetectionSettings.maximumContactDistance))
{
return(false);
}
//Colliding.
if (offsetLength > Toolbox.Epsilon)
{
offsetLength = (float)Math.Sqrt(offsetLength);
//Outside of the box.
Vector3.Divide(ref offset, offsetLength, out contact.Normal);
contact.PenetrationDepth = sphere.collisionMargin - offsetLength;
}
else
{
//Inside of the box.
Vector3 penetrationDepths;
penetrationDepths.X = localClosestPoint.X < 0 ? localClosestPoint.X + box.halfWidth : box.halfWidth - localClosestPoint.X;
penetrationDepths.Y = localClosestPoint.Y < 0 ? localClosestPoint.Y + box.halfHeight : box.halfHeight - localClosestPoint.Y;
penetrationDepths.Z = localClosestPoint.Z < 0 ? localClosestPoint.Z + box.halfLength : box.halfLength - localClosestPoint.Z;
if (penetrationDepths.X < penetrationDepths.Y && penetrationDepths.X < penetrationDepths.Z)
{
contact.Normal = localClosestPoint.X > 0 ? Toolbox.RightVector : Toolbox.LeftVector;
contact.PenetrationDepth = penetrationDepths.X;
}
else if (penetrationDepths.Y < penetrationDepths.Z)
{
contact.Normal = localClosestPoint.Y > 0 ? Toolbox.UpVector : Toolbox.DownVector;
contact.PenetrationDepth = penetrationDepths.Y;
}
else
{
contact.Normal = localClosestPoint.Z > 0 ? Toolbox.BackVector : Toolbox.ForwardVector;
contact.PenetrationDepth = penetrationDepths.Z;
}
contact.PenetrationDepth += sphere.collisionMargin;
Quaternion.Transform(ref contact.Normal, ref boxTransform.Orientation, out contact.Normal);
}
return(true);
}
///<summary>
/// Initializes the pair tester.
///</summary>
///<param name="convex">Convex shape to use.</param>
public override void Initialize(ConvexShape convex)
{
this.sphere = (SphereShape)convex;
}
