void setupParticleSystem(Autodesk.Revit.DB.Face f, int uDiv, int vDiv, double springDampening, double springRestLength, double springConstant, double mass)
{
BoundingBoxUV bbox = f.GetBoundingBox();
double uStep = (bbox.Max.U - bbox.Min.U) / uDiv;
double vStep = (bbox.Max.V - bbox.Min.V) / vDiv;
for (int j = 0; j <= uDiv; j++) // Y axis is outer loop
{
double u = bbox.Min.U + uStep * j;
for (int i = 0; i <= vDiv; i++) // X axis is inner loop
{
double v = bbox.Min.V + vStep * i;
Particle a = ParticleSystem.makeParticle(mass, f.Evaluate(new UV(u, v)), false);
if (i > 0)
{
ParticleSystem.makeSpring(ParticleSystem.getParticle((i - 1) + (j * (vDiv + 1))), a, springRestLength, springConstant, springDampening);
}
if (j > 0)
{
Particle b = ParticleSystem.getParticle(i + ((j - 1) * (vDiv + 1)));
ParticleSystem.makeSpring(a, b, springRestLength, springConstant, springDampening);
}
if (i == 0 || i == vDiv || j == 0 || j == uDiv)
{
a.makeFixed();
}
}
}
}
void CreateChainWithTwoFixedEnds(ReferencePoint pt1, ReferencePoint pt2, int numX, double springDampening, double springRestLength, double springConstant, double mass)
{
Particle p;
Particle p2;
XYZ partXYZ1 = pt1.Position;
XYZ partXYZ2 = pt2.Position;
XYZ lineVec = partXYZ2 - partXYZ1;
double stepSize = lineVec.GetLength() / numX;
for (int j = 0; j < numX; j++)//step along curve and evaluate at each step, making sure to thread in the existing fixed parts
{
//double curveParam = 0;
XYZ pointOnLine;
if (j == 0) // starting point
{
p = ParticleSystem.makeParticle(mass, partXYZ1, true); // make first particle fixed
}
else if (j > 0 && j < numX - 1) // middle points
{
pointOnLine = partXYZ1 + lineVec.Normalize() * (j * stepSize);
p = ParticleSystem.makeParticle(mass, pointOnLine, false); // make a new particle along curve at j-th point on line
p2 = ParticleSystem.getParticle(j - 1);
ParticleSystem.makeSpring(p, p2, springRestLength, springConstant, springDampening); //make a new spring and connect it to the last-made point
}
else //last point - fixed
{
p = ParticleSystem.getParticle(j - 1);
p2 = ParticleSystem.makeParticle(mass, partXYZ2, true); // make last particle fixed
ParticleSystem.makeSpring(p, p2, springRestLength, springConstant, springDampening); //make a new spring and connect the j-th point to the fixed point
}
}
}
void CreateChainWithOneFixedEnd(ReferencePoint pt1, int numX, double springDampening, double springRestLength, double springConstant, double mass)
{
Particle p;
XYZ partXYZ1 = pt1.Position;
Particle fixedPart1 = ParticleSystem.makeParticleFromElementID(pt1.Id, mass, pt1.Position, true); // true means 'make fixed'
XYZ partXYZ2 = partXYZ1 + new XYZ(10, 0, 0);
//Line tempLine = this.UIDocument.Application.Application.Create.NewLineBound(partXYZ1, partXYZ2);
XYZ vector = partXYZ2 - partXYZ1;
XYZ step = vector.Divide(numX);
for (int j = 0; j < numX; j++)//step along curve and evaluate at each step, making sure to thread in the existing fixed parts
{
//double curveParam = 0;
XYZ pointOnLine;
pointOnLine = partXYZ1 + step.Multiply(j);
if (j == 0) // starting point
{
//curveParam = (double)j / numX;
//pointOnLine = tempLine.Evaluate(curveParam, true);
p = ParticleSystem.makeParticle(mass, pointOnLine, true); // make first particle fixed
}
else // middle points
{
//curveParam = (double)j / numX;
//pointOnLine = tempLine.Evaluate(curveParam, true);
p = ParticleSystem.makeParticle(mass, pointOnLine, false); // make a new particle along curve at j-th point on line
ParticleSystem.makeSpring(ParticleSystem.getParticle((j - 1)), p, springRestLength, springConstant, springDampening); //make a new spring and connect it to the last-made point
}
}
}
public void Draw()
{
if (this.RenderDescription == null)
{
this.RenderDescription = new Nodes.RenderDescription();
}
if (particleSystem == null)
{
return;
}
for (int i = 0; i < particleSystem.numberOfParticles(); i++)
{
Particle p = particleSystem.getParticle(i);
XYZ pos = p.getPosition();
if (i < this.RenderDescription.points.Count())
{
this.RenderDescription.points[i] = new Point3D(pos.X, pos.Y, pos.Z);
}
else
{
Point3D pt = new System.Windows.Media.Media3D.Point3D(pos.X, pos.Y, pos.Z);
this.RenderDescription.points.Add(pt);
}
}
for (int i = 0; i < particleSystem.numberOfSprings(); i++)
{
ParticleSpring ps = particleSystem.getSpring(i);
XYZ pos1 = ps.getOneEnd().getPosition();
XYZ pos2 = ps.getTheOtherEnd().getPosition();
if (i * 2 + 1 < this.RenderDescription.lines.Count())
{
this.RenderDescription.lines[i * 2] = new Point3D(pos1.X, pos1.Y, pos1.Z);
this.RenderDescription.lines[i * 2 + 1] = new Point3D(pos2.X, pos2.Y, pos2.Z);
}
else
{
Point3D pt1 = new System.Windows.Media.Media3D.Point3D(pos1.X, pos1.Y, pos1.Z);
Point3D pt2 = new System.Windows.Media.Media3D.Point3D(pos2.X, pos2.Y, pos2.Z);
this.RenderDescription.lines.Add(pt1);
this.RenderDescription.lines.Add(pt2);
}
}
}
public void Draw()
{
if (RenderDescription == null)
{
RenderDescription = new RenderDescription();
}
if (ParticleSystem == null)
{
return;
}
for (int i = 0; i < ParticleSystem.numberOfParticles(); i++)
{
Particle p = ParticleSystem.getParticle(i);
XYZ pos = p.getPosition();
if (i < RenderDescription.points.Count())
{
RenderDescription.points[i] = new Point3D(pos.X, pos.Y, pos.Z);
}
else
{
var pt = new Point3D(pos.X, pos.Y, pos.Z);
RenderDescription.points.Add(pt);
}
}
for (int i = 0; i < ParticleSystem.numberOfSprings(); i++)
{
ParticleSpring ps = ParticleSystem.getSpring(i);
XYZ pos1 = ps.getOneEnd().getPosition();
XYZ pos2 = ps.getTheOtherEnd().getPosition();
if (i * 2 + 1 < RenderDescription.lines.Count())
{
RenderDescription.lines[i * 2] = new Point3D(pos1.X, pos1.Y, pos1.Z);
RenderDescription.lines[i * 2 + 1] = new Point3D(pos2.X, pos2.Y, pos2.Z);
}
else
{
var pt1 = new Point3D(pos1.X, pos1.Y, pos1.Z);
var pt2 = new Point3D(pos2.X, pos2.Y, pos2.Z);
RenderDescription.lines.Add(pt1);
RenderDescription.lines.Add(pt2);
}
}
}
public override Value Evaluate(FSharpList <Value> args)
{
ParticleSystem particleSystem = (ParticleSystem)((Value.Container)args[0]).Item;
var result = FSharpList <Value> .Empty;
Particle p;
XYZ pt;
//create an XYZ from each Particle
for (int i = 0; i < particleSystem.numberOfParticles(); i++)
{
p = particleSystem.getParticle(i);
pt = new XYZ(p.getPosition().X, p.getPosition().Y, p.getPosition().Z);
result = FSharpList <Value> .Cons(Value.NewContainer(pt), result);
}
return(Value.NewList(result));
}
private void UpdateSystem()
{
//update the spring values
for (int j = 0; j < ParticleSystem.numberOfSprings(); j++)
{
ParticleSpring spring = ParticleSystem.getSpring(j);
spring.setDamping(_d);
if (!_useRl)
{
spring.setRestLength(_r);
}
spring.setSpringConstant(_s);
}
for (int j = 0; j < ParticleSystem.numberOfParticles(); j++)
{
Particle p = ParticleSystem.getParticle(j);
p.setMass(_m);
}
}
void setupLineTest(int maxPartX, int maxPartY, double springDampening, double springRestLength, double springConstant, double mass)
{
XYZ partXYZ;
double stepSize = 20;
for (int j = 0; j < maxPartY; j++) // Y axis is outer loop
{
for (int i = 0; i < maxPartX; i++) // X axis is inner loop
{
if (i == 0)
{
partXYZ = new XYZ(0, j * stepSize, 0);
Particle a = ParticleSystem.makeParticle(mass, partXYZ, true);
}
else
{
partXYZ = new XYZ(i * stepSize, j * stepSize, 0);
Particle b = ParticleSystem.makeParticle(mass, partXYZ, false);
ParticleSystem.makeSpring(ParticleSystem.getParticle((i - 1) + (j * maxPartX)), b, springRestLength, springConstant, springDampening);
}
if (i == maxPartX - 1)
{
ParticleSystem.getParticle(i + (j * maxPartX)).makeFixed();
}
}
if (j > 0) // thread multple chains together along Y axis
{
for (int i = 0; i < maxPartX; i++)
{
Particle a = ParticleSystem.getParticle(i + (j * maxPartX));
Particle b = ParticleSystem.getParticle(i + ((j - 1) * maxPartX));
ParticleSystem.makeSpring(a, b, springRestLength, springConstant, springDampening);
}
}
}
}
public void step(double t)
{
s.clearForces();
s.applyForces();
double halftt = 0.5 * t * t;
double tt = t * t;
for (int i = 0; i < s.numberOfParticles(); i++)
{
Particle p = s.getParticle(i);
if (p.isFree())
{
XYZ a = p.getForce() / p.getMass();
XYZ xmm = p.getOldPosition();
XYZ xm = p.getPosition();
XYZ x = xm.Add(xm - xmm) + a * tt;
XYZ vm = p.getVelocity();
p.setPosition(x);
p.setVelocity((x - xmm) / (2 * t));
}
}
}