protected void applyHookesLaw(bool twoD = false)
{
foreach (var e in Graph.Edges)
{
SpringFD spring = GetSpring(e);
Vector3 d = spring.point2.Position - spring.point1.Position;
float displacement = spring.Length - d.magnitude;
Vector3 direction = d.normalized;
if (twoD)
{
direction.z = 0;
}
if (spring.point1.Pinned && spring.point2.Pinned)
{
spring.point1.ApplyForce(direction * 0.0f);
spring.point2.ApplyForce(direction * 0.0f);
}
else if (spring.point1.Pinned)
{
spring.point1.ApplyForce(direction * 0.0f);
spring.point2.ApplyForce(direction * (spring.K * displacement));
}
else if (spring.point2.Pinned)
{
spring.point1.ApplyForce(direction * (spring.K * displacement * -1.0f));
spring.point2.ApplyForce(direction * 0.0f);
}
else
{
spring.point1.ApplyForce(direction * (spring.K * displacement * -0.5f));
spring.point2.ApplyForce(direction * (spring.K * displacement * 0.5f));
}
}
}
//get spring associated to edge
public SpringFD GetSpring(IEdge <INode> edge)
{
//if (!(m_edgeSprings.ContainsKey(edge.Uid)))
//{
// float length = GetEdgeLength(edge);
// SpringFD existingSpring = null;
// List<IEdge<INode>> fromEdges = (SimpleGraph)Graph.GetEdges(edge.Source, edge.Target);
// if (fromEdges != null)
// {
// foreach (Edge e in fromEdges)
// {
// if (existingSpring == null && m_edgeSprings.ContainsKey(e.ID))
// {
// existingSpring = m_edgeSprings[e.ID];
// break;
// }
// }
// }
// if (existingSpring != null)
// {
// return new SpringFD(existingSpring.point1, existingSpring.point2, 0.0f, 0.0f);
// }
// List<Edge> toEdges = Graph.GetEdges(edge.Target, edge.Source);
// if (toEdges != null)
// {
// foreach (Edge e in toEdges)
// {
// if (existingSpring == null && m_edgeSprings.ContainsKey(e.ID))
// {
// existingSpring = m_edgeSprings[e.ID];
// break;
// }
// }
// }
// if (existingSpring != null)
// {
// return new SpringFD(existingSpring.point2, existingSpring.point1, 0.0f, 0.0f);
// }
// m_edgeSprings[edge.ID] = new SpringFD(GetPoint(edge.Source), GetPoint(edge.Target), length, Stiffness);
//}
//return m_edgeSprings[edge.Uid];
SpringFD spring;
if (!m_edgeSprings.TryGetValue(edge.Uid, out spring))
{
spring = new SpringFD(GetPoint(edge.Source), GetPoint(edge.Target), GetEdgeLength(edge), Stiffness);
m_edgeSprings.Add(edge.Uid, spring);
}
return(m_edgeSprings[edge.Uid]);
}