/**
* Updates the particle view. This should be called on each draw cycle in order to update the
* positions of all nodes and edges in the viewer. If you need to update the positions of
* particles without drawing it (e.g. to speed up movement, call updateParticles() instead.
*/
public void draw() {
parent.pushStyle();
parent.pushMatrix();
zoomer.transform();
updateCentroid();
centroid.tick();
parent.translate(width / 2, height / 2);
parent.scale(centroid.getZ());
parent.translate(-centroid.getX(), -centroid.getY());
if (!isPaused) {
updateParticles();
}
// Ensure that any selected element is positioned at the mouse location.
if (selectedNode != null) {
Particle p = nodes.get(selectedNode);
p.makeFixed();
float mX = (zoomer.getMouseCoord().x - (width / 2)) / centroid.getZ() + centroid.getX();
float mY = (zoomer.getMouseCoord().y - (height / 2)) / centroid.getZ() + centroid.getY();
p.position().set(mX, mY, 0);
}
// Draw edges if we have positive stroke weight.
if (parent.g.strokeWeight > 0) {
parent.stroke(0, 180);
parent.noFill();
for (Map.Entry<E, Spring> row : edges.entrySet()) {
E edge = row.getKey();
Spring spring = row.getValue();
Vector3D p1 = spring.getOneEnd().position();
Vector3D p2 = spring.getTheOtherEnd().position();
edge.draw(parent, p1.x(), p1.y(), p2.x(), p2.y());
}
}
// Draw nodes.
parent.noStroke();
parent.fill(120, 50, 50, 180);
for (Map.Entry<N, Particle> row : nodes.entrySet()) {
N node = row.getKey();
Vector3D p = row.getValue().position();
node.draw(parent, p.x(), p.y());
}
parent.popMatrix();
parent.popStyle();
}
/**
* Tethers the given node to its location with the given strength.
*
* @param node The node to be tethered.
* @param strength Strength of the tether.
* @return True if the viewer contains the given node and it was tethered successfully.
*/
public boolean tether(N node, float strength) {
Particle p1 = nodes.get(node);
if (p1 == null) {
return false;
}
// Grab the tethering stake if it has already been created, otherwise create a new one.
Particle stake = stakes.get(node);
if (stake == null) {
stake = physics.makeParticle(1, node.getLocation().x, node.getLocation().y, 0);
stake.makeFixed();
stakes.put(node, stake);
}
// Grab the tether if it has already been created, otherwise create a new one.
Spring tether = tethers.get(stake);
if (tether == null) {
tether = physics.makeSpring(stake, p1, strength, DAMPING, Float.MIN_VALUE);
tethers.put(stake, tether);
} else {
tether.setStrength(strength);
}
return true;
}