/* Always call this on the root node.
If you call this from another node,
you're a dick. */
void QTnode::calc_global_accel()
{
int i;
QTnode *t;
std::queue <QTnode *> nodes;
nodes.push(this);
/* Perform a breadth-first traversal
through all particles. */
while (!nodes.empty()) {
t = nodes.front();
nodes.pop();
if (t->children.empty()) {
for (std::list <Particle>::iterator p = t->particles.begin(); p != t->particles.end(); p++) {
(*p).accel = calc_accel(*p);
// printf("Particle has accel <%lf, %lf>\n", (*p).accel.x, (*p).accel.y);
}
} else {
for (i = 0; i < t->children.size(); i++) {
nodes.push(t->children[i]);
}
}
}
}
/**
* @todo:
* Make the storage of the previous calculated acceleration working.
*/
void integration_leap_frog(listv2d& r, listv2d& v, listv2d& a, const listdouble& m, double h, double ti) {
// Store the previous accellerations so they don't have to be calculcated again
static listv2d previous_accel;
if (previous_accel.size() == 0) {
for (int i = 0; i < ITEMS; i++) {
previous_accel.push_back(calc_accel(r, m, i));
}
}
listv2d v1(ITEMS);
for (int i = 0; i < ITEMS; i++) {
// Use previous calculated f(t) for the new speed.
v1[i] = v[i] + 0.5 * h * previous_accel[i];
r[i] = r[i] + h * v1[i];
}
for (int i = 0; i < ITEMS; i++) {
//Calculate f(t+1) for the new speed.
previous_accel[i] = calc_accel(r, m, i);
v[i] = v1[i] + 0.5 * h * previous_accel[i];
}
}
/**
* Calculate the accelleration of all bodies.
*/
void calc_accel_multiple(const listv2d& r, listv2d& a, const vector<double>&m) {
for (int i = 0; i < ITEMS; i++) {
a[i] = calc_accel(r, m, i);
}
}
