--- /dev/null
+/**
+ * jsPlumbGeom v0.1
+ *
+ * Various geometry functions written as part of jsPlumb and perhaps useful for others.
+ *
+ * Copyright (c) 2013 Simon Porritt
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+;(function() {
+
+
+ "use strict";
+
+ // Establish the root object, `window` in the browser, or `global` on the server.
+ var root = this;
+ var jsPlumbGeom;
+ if (typeof exports !== 'undefined') {
+ jsPlumbGeom = exports;
+ } else {
+ jsPlumbGeom = root.jsPlumbGeom = {};
+ }
+
+ var _isa = function(a) { return Object.prototype.toString.call(a) === "[object Array]"; },
+ _pointHelper = function(p1, p2, fn) {
+ p1 = _isa(p1) ? p1 : [p1.x, p1.y];
+ p2 = _isa(p2) ? p2 : [p2.x, p2.y];
+ return fn(p1, p2);
+ },
+ /**
+ * @name jsPlumbGeom.gradient
+ * @function
+ * @desc Calculates the gradient of a line between the two points.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Float} The gradient of a line between the two points.
+ */
+ _gradient = jsPlumbGeom.gradient = function(p1, p2) {
+ return _pointHelper(p1, p2, function(_p1, _p2) {
+ if (_p2[0] == _p1[0])
+ return _p2[1] > _p1[1] ? Infinity : -Infinity;
+ else if (_p2[1] == _p1[1])
+ return _p2[0] > _p1[0] ? 0 : -0;
+ else
+ return (_p2[1] - _p1[1]) / (_p2[0] - _p1[0]);
+ });
+ },
+ /**
+ * @name jsPlumbGeom.normal
+ * @function
+ * @desc Calculates the gradient of a normal to a line between the two points.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Float} The gradient of a normal to a line between the two points.
+ */
+ _normal = jsPlumbGeom.normal = function(p1, p2) {
+ return -1 / _gradient(p1, p2);
+ },
+ /**
+ * @name jsPlumbGeom.lineLength
+ * @function
+ * @desc Calculates the length of a line between the two points.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Float} The length of a line between the two points.
+ */
+ _lineLength = jsPlumbGeom.lineLength = function(p1, p2) {
+ return _pointHelper(p1, p2, function(_p1, _p2) {
+ return Math.sqrt(Math.pow(_p2[1] - _p1[1], 2) + Math.pow(_p2[0] - _p1[0], 2));
+ });
+ },
+ /**
+ * @name jsPlumbGeom.quadrant
+ * @function
+ * @desc Calculates the quadrant in which the angle between the two points lies.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Integer} The quadrant - 1 for upper right, 2 for lower right, 3 for lower left, 4 for upper left.
+ */
+ _quadrant = jsPlumbGeom.quadrant = function(p1, p2) {
+ return _pointHelper(p1, p2, function(_p1, _p2) {
+ if (_p2[0] > _p1[0]) {
+ return (_p2[1] > _p1[1]) ? 2 : 1;
+ }
+ else if (_p2[0] == _p1[0]) {
+ return _p2[1] > _p1[1] ? 2 : 1;
+ }
+ else {
+ return (_p2[1] > _p1[1]) ? 3 : 4;
+ }
+ });
+ },
+ /**
+ * @name jsPlumbGeom.theta
+ * @function
+ * @desc Calculates the angle between the two points.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Float} The angle between the two points.
+ */
+ _theta = jsPlumbGeom.theta = function(p1, p2) {
+ return _pointHelper(p1, p2, function(_p1, _p2) {
+ var m = _gradient(_p1, _p2),
+ t = Math.atan(m),
+ s = _quadrant(_p1, _p2);
+ if ((s == 4 || s== 3)) t += Math.PI;
+ if (t < 0) t += (2 * Math.PI);
+
+ return t;
+ });
+ },
+ /**
+ * @name jsPlumbGeom.intersects
+ * @function
+ * @desc Calculates whether or not the two rectangles intersect.
+ * @param {Rectangle} r1 First rectangle, as a js object in the form `{x:.., y:.., w:.., h:..}`
+ * @param {Rectangle} r2 Second rectangle, as a js object in the form `{x:.., y:.., w:.., h:..}`
+ * @return {Boolean} True if the rectangles intersect, false otherwise.
+ */
+ _intersects = jsPlumbGeom.intersects = function(r1, r2) {
+ var x1 = r1.x, x2 = r1.x + r1.w, y1 = r1.y, y2 = r1.y + r1.h,
+ a1 = r2.x, a2 = r2.x + r2.w, b1 = r2.y, b2 = r2.y + r2.h;
+
+ return ( (x1 <= a1 && a1 <= x2) && (y1 <= b1 && b1 <= y2) ) ||
+ ( (x1 <= a2 && a2 <= x2) && (y1 <= b1 && b1 <= y2) ) ||
+ ( (x1 <= a1 && a1 <= x2) && (y1 <= b2 && b2 <= y2) ) ||
+ ( (x1 <= a2 && a1 <= x2) && (y1 <= b2 && b2 <= y2) ) ||
+ ( (a1 <= x1 && x1 <= a2) && (b1 <= y1 && y1 <= b2) ) ||
+ ( (a1 <= x2 && x2 <= a2) && (b1 <= y1 && y1 <= b2) ) ||
+ ( (a1 <= x1 && x1 <= a2) && (b1 <= y2 && y2 <= b2) ) ||
+ ( (a1 <= x2 && x1 <= a2) && (b1 <= y2 && y2 <= b2) );
+ },
+ _segmentMultipliers = [null, [1, -1], [1, 1], [-1, 1], [-1, -1] ],
+ _inverseSegmentMultipliers = [null, [-1, -1], [-1, 1], [1, 1], [1, -1] ],
+ /**
+ * @name jsPlumbGeom.pointOnLine
+ * @function
+ * @desc Calculates a point on the line from `fromPoint` to `toPoint` that is `distance` units along the length of the line.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Point} Point on the line, in the form `{ x:..., y:... }`.
+ */
+ _pointOnLine = jsPlumbGeom.pointOnLine = function(fromPoint, toPoint, distance) {
+ var m = _gradient(fromPoint, toPoint),
+ s = _quadrant(fromPoint, toPoint),
+ segmentMultiplier = distance > 0 ? _segmentMultipliers[s] : _inverseSegmentMultipliers[s],
+ theta = Math.atan(m),
+ y = Math.abs(distance * Math.sin(theta)) * segmentMultiplier[1],
+ x = Math.abs(distance * Math.cos(theta)) * segmentMultiplier[0];
+ return { x:fromPoint.x + x, y:fromPoint.y + y };
+ },
+ /**
+ * @name jsPlumbGeom.perpendicularLineTo
+ * @function
+ * @desc Calculates a line of length `length` that is perpendicular to the line from `fromPoint` to `toPoint` and passes through `toPoint`.
+ * @param {Point} p1 First point, either as a 2 entry array or object with `left` and `top` properties.
+ * @param {Point} p2 Second point, either as a 2 entry array or object with `left` and `top` properties.
+ * @return {Line} Perpendicular line, in the form `[ { x:..., y:... }, { x:..., y:... } ]`.
+ */
+ _perpendicularLineTo = jsPlumbGeom.perpendicularLineTo = function(fromPoint, toPoint, length) {
+ var m = _gradient(fromPoint, toPoint),
+ theta2 = Math.atan(-1 / m),
+ y = length / 2 * Math.sin(theta2),
+ x = length / 2 * Math.cos(theta2);
+ return [{x:toPoint.x + x, y:toPoint.y + y}, {x:toPoint.x - x, y:toPoint.y - y}];
+ };
+}).call(this);
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git://git.onelab.eu / unfold.git / blobdiff