public void Simulate(double dt)
{
if (dragging)
{
VectorN dragForce = new VectorN(2);
dragForce.v[0] = mousex - dragged.pos.v[0];
dragForce.v[1] = mousey - dragged.pos.v[1];
dragForce.Scale(50 * dragged.mass);
dragged.ApplyForce(dragForce);
dragged.Unfreeze();
}
for (int i = 0; i < particles.Count; i++)
{
if (particles[i] != dragged)
{
particles[i].ApplyGravity();
}
}
dynamics.SimulateFast(dt);
CheckBounds();
}
private void CheckBounds()
{
double restitution = 0.6;
double erp = 0.3;
for (int i = 0; i < particles.Count; i++)
{
double[] pos = particles[i].pos.v;
double r = particles[i].radius;
if (pos[0] < leftBound + r || pos[0] > rightBound - r ||
pos[1] > topBound - r || pos[1] < bottomBound + r)
{
double penetration = 0;
VectorN dir = new VectorN(2);
particles[i].v.Scale(restitution);
if (pos[0] < leftBound + r)
{
particles[i].v.v[0] *= -1;
penetration = leftBound - pos[0] + r;
dir.v[0] = 1;
}
if (pos[0] > rightBound - r)
{
particles[i].v.v[0] *= -1;
penetration = pos[0] - rightBound + r;
dir.v[0] = -1;
}
if (pos[1] > topBound - r)
{
particles[i].v.v[1] *= -1;
penetration = pos[1] - topBound + r;
dir.v[1] = -1;
}
if (pos[1] < bottomBound + r)
{
particles[i].v.v[1] *= -1;
penetration = bottomBound - pos[1] + r;
dir.v[1] = 1;
}
particles[i].v.Scale(restitution);
VectorN additional = particles[i].v.NormalizeR();
particles[i].v.Add(additional.ScaleR(penetration * erp));
dir.Scale(penetration);
particles[i].pos.Add(dir);
}
}
}