import BarnesHutSolver from "./BarnesHutSolver" class ForceAtlas2BasedRepulsionSolver extends BarnesHutSolver { constructor(body, physicsBody, options) { super(body, physicsBody, options); } /** * Calculate the forces based on the distance. * * @param distance * @param dx * @param dy * @param node * @param parentBranch * @private */ _calculateForces(distance, dx, dy, node, parentBranch) { if (distance === 0) { distance = 0.1 * Math.random(); dx = distance; } let degree = (node.edges.length + 1); // the dividing by the distance cubed instead of squared allows us to get the fx and fy components without sines and cosines // it is shorthand for gravityforce with distance squared and fx = dx/distance * gravityForce let gravityForce = this.options.gravitationalConstant * parentBranch.mass * node.options.mass * degree / Math.pow(distance,2); let fx = dx * gravityForce; let fy = dy * gravityForce; this.physicsBody.forces[node.id].x += fx; this.physicsBody.forces[node.id].y += fy; } } export default ForceAtlas2BasedRepulsionSolver;