// Function to update location
public void update() {
// As long as we aren't dragging the pendulum, let it swing!
if (!dragging) {
float G = 0.4f; // Arbitrary universal gravitational constant
theta_acc = (-1 * G / r) * sin(theta); // Calculate acceleration (see:
// http://www.myphysicslab.com/pendulum1.html)
theta_vel += theta_acc; // Increment velocity
theta_vel *= damping; // Arbitrary damping
theta += theta_vel; // Increment theta
}
loc.setXY(r * sin(theta), r * cos(theta)); // Polar to cartesian conversion
loc.add(origin); // Make sure the location is relative to the pendulum's origin
}
void wander() {
float wanderR = 10.0f; // radius for our "wander circle"
float wanderD = 20.0f; // distance for our "wander circle"
wandertheta += random(-1, 1); // randomly changet wander theta
// now we have to calculate the new location to steer towards on the wander circle
Vector3D v = vel.copy();
v.normalize(); // our heading
float xoff =
wanderD * v.x() + wanderR * cos(wandertheta); // x spot on circle based on heading
float yoff =
wanderD * v.y() + wanderR * sin(wandertheta); // y spot on circle based on heading
Vector3D target = Vector3D.add(loc, new Vector3D(xoff, yoff)); // add the location
acc.add(steer(target, false)); // steer towards it
}
// function to update location
void update() {
vel.add(acc);
loc.add(vel);
timer -= 1.0f;
}