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- /**
- * Created by Alex on 3/20/2015.
- */
-
- import BaseEdge from './baseEdge'
-
- class BezierBaseEdge extends BaseEdge {
- constructor(options, body, labelModule) {
- super(options, body, labelModule);
- }
-
- /**
- * This function uses binary search to look for the point where the bezier curve crosses the border of the node.
- *
- * @param nearNode
- * @param ctx
- * @param viaNode
- * @param nearNode
- * @param ctx
- * @param viaNode
- * @param nearNode
- * @param ctx
- * @param viaNode
- */
- _findBorderPositionBezier(nearNode, ctx, viaNode = this._getViaCoordinates()) {
- console.log(nearNode, ctx, viaNode)
-
- var maxIterations = 10;
- var iteration = 0;
- var low = 0;
- var high = 1;
- var pos, angle, distanceToBorder, distanceToPoint, difference;
- var threshold = 0.2;
- var node = this.to;
- var from = false;
- if (nearNode.id === this.from.id) {
- node = this.from;
- from = true;
- }
-
- while (low <= high && iteration < maxIterations) {
- var middle = (low + high) * 0.5;
-
- pos = this.getPoint(middle, viaNode);
- angle = Math.atan2((node.y - pos.y), (node.x - pos.x));
- distanceToBorder = node.distanceToBorder(ctx, angle);
- distanceToPoint = Math.sqrt(Math.pow(pos.x - node.x, 2) + Math.pow(pos.y - node.y, 2));
- difference = distanceToBorder - distanceToPoint;
- if (Math.abs(difference) < threshold) {
- break; // found
- }
- else if (difference < 0) { // distance to nodes is larger than distance to border --> t needs to be bigger if we're looking at the to node.
- if (from == false) {
- low = middle;
- }
- else {
- high = middle;
- }
- }
- else {
- if (from == false) {
- high = middle;
- }
- else {
- low = middle;
- }
- }
-
- iteration++;
- }
- pos.t = middle;
-
- return pos;
- }
-
-
-
- /**
- * Calculate the distance between a point (x3,y3) and a line segment from
- * (x1,y1) to (x2,y2).
- * http://stackoverflow.com/questions/849211/shortest-distancae-between-a-point-and-a-line-segment
- * @param {number} x1
- * @param {number} y1
- * @param {number} x2
- * @param {number} y2
- * @param {number} x3
- * @param {number} y3
- * @private
- */
- _getDistanceToBezierEdge(x1, y1, x2, y2, x3, y3, via) { // x3,y3 is the point
- let xVia, yVia;
- xVia = via.x;
- yVia = via.y;
- let minDistance = 1e9;
- let distance;
- let i, t, x, y;
- let lastX = x1;
- let lastY = y1;
- for (i = 1; i < 10; i++) {
- t = 0.1 * i;
- x = Math.pow(1 - t, 2) * x1 + (2 * t * (1 - t)) * xVia + Math.pow(t, 2) * x2;
- y = Math.pow(1 - t, 2) * y1 + (2 * t * (1 - t)) * yVia + Math.pow(t, 2) * y2;
- if (i > 0) {
- distance = this._getDistanceToLine(lastX, lastY, x, y, x3, y3);
- minDistance = distance < minDistance ? distance : minDistance;
- }
- lastX = x;
- lastY = y;
- }
-
- return minDistance;
- }
- }
-
- export default BezierBaseEdge;
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