/**
* This helper method calculates the repulsive forces acting on a node from all the other nodes in
* the graph. BIG O( number of nodes )
*
* <p>There is a repulsive force between every nodes depending on the distance separating them and
* their size.
*
* @param current node to calculate forces for.
*/
private void calculateNodeRepulsiveForces(Node current) {
Iterator<Node> inner = controller.getNodeIterator();
int current_radius, n_radius, dx, dy;
Node n;
current_radius =
(int) Math.sqrt(Math.pow(current.getWidth(), 2) + Math.pow(current.getHeight(), 2));
while (inner.hasNext()) {
n = inner.next();
if (n != current) {
dx = current.getX() - n.getX();
dy = current.getY() - n.getY();
n_radius = (int) Math.sqrt(Math.pow(n.getWidth(), 2) + Math.pow(n.getHeight(), 2));
// only repel if nodes are connected or within diameter * MAX_REPEL_DISTANCE
// if (Math.sqrt(dx * dx + dy * dy) < (Math.max(current_radius, n_radius) *
// MAX_REPEL_MULTIPLIER)) {
double l = (dx * dx + dy * dy) + .1;
if (l > 0) {
// current.setVX(current.getVX() + dx * (current_radius * SPACING) / l);
// current.setVY(current.getVY() + dy * (current_radius * SPACING) / l);
current.accelx += (dx * REPULSION / (l)) / current.weight;
current.accely += (dy * REPULSION / (l)) / current.weight;
// current.accelx += (dx * SPACING / (l * .5)) / current.weight;
// current.accely += (dy * SPACING / (l * .5)) / current.weight;
// n.accelx += (dx * SPACING / (l * -0.5)) / n.weight;
// n.accely += (dy * SPACING / (l * -0.5)) / n.weight;
}
// }
}
}
}
/**
* This helper calculates all the attractive forces onto a node. Attractive forces from from the
* edges pulling nodes towards each other, this will love through the edges of this node.
*
* @param current Node to calculate forces for.
*/
private void calculateNodeAttractiveForce(Node current) {
// get all the edges of the current node
ArrayList<Edge> nodeEdgeList = current.getEdgeList();
// of each of this node's edge do attactive forces
Iterator<Edge> nodeEdges = nodeEdgeList.iterator();
///
int numOfEdgesWeight = 10 * (int) Math.round(nodeEdgeList.size() + SPACING);
// Loop through edges and find edges containing current node
while (nodeEdges.hasNext()) {
Edge e = nodeEdges.next();
double edgeStrength = e.getStrength();
Node n;
int dx, dy;
double sign = 1.0;
if (current == e.getNode1()) {
n = e.getNode2();
dx = current.getX() - n.getX();
dy = current.getY() - n.getY();
} else {
n = e.getNode1();
dx = current.getX() - n.getX();
dy = current.getY() - n.getY();
sign = -1.0;
}
double distance = Math.sqrt(dx * dx + dy * dy) + .1;
// multiply by the strength of edge
// current.setVX(current.getVX() - dx / numOfEdgesWeight * edgeStrength);
// current.setVY(current.getVY() - dy / numOfEdgesWeight * edgeStrength);
current.accelx += sign * (dx * STIFFNESS * (SPRING_LENGTH - distance)) / current.weight;
current.accely += sign * (dy * STIFFNESS * (SPRING_LENGTH - distance)) / current.weight;
// current.accelx += sign * (dx * (e.getStrength() + 1) * (SPRING_LENGTH - distance) * 0.5) /
// current.weight;
// current.accely += sign * (dy * (e.getStrength() + 1) * (SPRING_LENGTH - distance) * 0.5) /
// current.weight;
// n.accelx += sign * (dx * (e.getStrength() + 1) * (SPRING_LENGTH - distance) * 0.5) /
// n.weight;
// n.accely += sign * (dy * (e.getStrength() + 1) * (SPRING_LENGTH - distance) * 0.5) /
// n.weight;
}
}