simple-squiggle

A restricted subset of Squiggle
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intersect.js (9029B)


      1 "use strict";
      2 
      3 Object.defineProperty(exports, "__esModule", {
      4   value: true
      5 });
      6 exports.createIntersect = void 0;
      7 
      8 var _factory = require("../../utils/factory.js");
      9 
     10 var name = 'intersect';
     11 var dependencies = ['typed', 'config', 'abs', 'add', 'addScalar', 'matrix', 'multiply', 'multiplyScalar', 'divideScalar', 'subtract', 'smaller', 'equalScalar', 'flatten', 'isZero', 'isNumeric'];
     12 var createIntersect = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
     13   var typed = _ref.typed,
     14       config = _ref.config,
     15       abs = _ref.abs,
     16       add = _ref.add,
     17       addScalar = _ref.addScalar,
     18       matrix = _ref.matrix,
     19       multiply = _ref.multiply,
     20       multiplyScalar = _ref.multiplyScalar,
     21       divideScalar = _ref.divideScalar,
     22       subtract = _ref.subtract,
     23       smaller = _ref.smaller,
     24       equalScalar = _ref.equalScalar,
     25       flatten = _ref.flatten,
     26       isZero = _ref.isZero,
     27       isNumeric = _ref.isNumeric;
     28 
     29   /**
     30    * Calculates the point of intersection of two lines in two or three dimensions
     31    * and of a line and a plane in three dimensions. The inputs are in the form of
     32    * arrays or 1 dimensional matrices. The line intersection functions return null
     33    * if the lines do not meet.
     34    *
     35    * Note: Fill the plane coefficients as `x + y + z = c` and not as `x + y + z + c = 0`.
     36    *
     37    * Syntax:
     38    *
     39    *    math.intersect(endPoint1Line1, endPoint2Line1, endPoint1Line2, endPoint2Line2)
     40    *    math.intersect(endPoint1, endPoint2, planeCoefficients)
     41    *
     42    * Examples:
     43    *
     44    *    math.intersect([0, 0], [10, 10], [10, 0], [0, 10])              // Returns [5, 5]
     45    *    math.intersect([0, 0, 0], [10, 10, 0], [10, 0, 0], [0, 10, 0])  // Returns [5, 5, 0]
     46    *    math.intersect([1, 0, 1],  [4, -2, 2], [1, 1, 1, 6])            // Returns [7, -4, 3]
     47    *
     48    * @param  {Array | Matrix} w   Co-ordinates of first end-point of first line
     49    * @param  {Array | Matrix} x   Co-ordinates of second end-point of first line
     50    * @param  {Array | Matrix} y   Co-ordinates of first end-point of second line
     51    *                              OR Co-efficients of the plane's equation
     52    * @param  {Array | Matrix} z   Co-ordinates of second end-point of second line
     53    *                              OR undefined if the calculation is for line and plane
     54    * @return {Array}              Returns the point of intersection of lines/lines-planes
     55    */
     56   return typed('intersect', {
     57     'Array, Array, Array': _AAA,
     58     'Array, Array, Array, Array': _AAAA,
     59     'Matrix, Matrix, Matrix': function MatrixMatrixMatrix(x, y, plane) {
     60       var arr = _AAA(x.valueOf(), y.valueOf(), plane.valueOf());
     61 
     62       return arr === null ? null : matrix(arr);
     63     },
     64     'Matrix, Matrix, Matrix, Matrix': function MatrixMatrixMatrixMatrix(w, x, y, z) {
     65       // TODO: output matrix type should match input matrix type
     66       var arr = _AAAA(w.valueOf(), x.valueOf(), y.valueOf(), z.valueOf());
     67 
     68       return arr === null ? null : matrix(arr);
     69     }
     70   });
     71 
     72   function _AAA(x, y, plane) {
     73     x = _coerceArr(x);
     74     y = _coerceArr(y);
     75     plane = _coerceArr(plane);
     76 
     77     if (!_3d(x)) {
     78       throw new TypeError('Array with 3 numbers or BigNumbers expected for first argument');
     79     }
     80 
     81     if (!_3d(y)) {
     82       throw new TypeError('Array with 3 numbers or BigNumbers expected for second argument');
     83     }
     84 
     85     if (!_4d(plane)) {
     86       throw new TypeError('Array with 4 numbers expected as third argument');
     87     }
     88 
     89     return _intersectLinePlane(x[0], x[1], x[2], y[0], y[1], y[2], plane[0], plane[1], plane[2], plane[3]);
     90   }
     91 
     92   function _AAAA(w, x, y, z) {
     93     w = _coerceArr(w);
     94     x = _coerceArr(x);
     95     y = _coerceArr(y);
     96     z = _coerceArr(z);
     97 
     98     if (w.length === 2) {
     99       if (!_2d(w)) {
    100         throw new TypeError('Array with 2 numbers or BigNumbers expected for first argument');
    101       }
    102 
    103       if (!_2d(x)) {
    104         throw new TypeError('Array with 2 numbers or BigNumbers expected for second argument');
    105       }
    106 
    107       if (!_2d(y)) {
    108         throw new TypeError('Array with 2 numbers or BigNumbers expected for third argument');
    109       }
    110 
    111       if (!_2d(z)) {
    112         throw new TypeError('Array with 2 numbers or BigNumbers expected for fourth argument');
    113       }
    114 
    115       return _intersect2d(w, x, y, z);
    116     } else if (w.length === 3) {
    117       if (!_3d(w)) {
    118         throw new TypeError('Array with 3 numbers or BigNumbers expected for first argument');
    119       }
    120 
    121       if (!_3d(x)) {
    122         throw new TypeError('Array with 3 numbers or BigNumbers expected for second argument');
    123       }
    124 
    125       if (!_3d(y)) {
    126         throw new TypeError('Array with 3 numbers or BigNumbers expected for third argument');
    127       }
    128 
    129       if (!_3d(z)) {
    130         throw new TypeError('Array with 3 numbers or BigNumbers expected for fourth argument');
    131       }
    132 
    133       return _intersect3d(w[0], w[1], w[2], x[0], x[1], x[2], y[0], y[1], y[2], z[0], z[1], z[2]);
    134     } else {
    135       throw new TypeError('Arrays with two or thee dimensional points expected');
    136     }
    137   }
    138   /** Coerce row and column 2-dim arrays to 1-dim array */
    139 
    140 
    141   function _coerceArr(arr) {
    142     // row matrix
    143     if (arr.length === 1) return arr[0]; // column matrix
    144 
    145     if (arr.length > 1 && Array.isArray(arr[0])) {
    146       if (arr.every(function (el) {
    147         return Array.isArray(el) && el.length === 1;
    148       })) return flatten(arr);
    149     }
    150 
    151     return arr;
    152   }
    153 
    154   function _2d(x) {
    155     return x.length === 2 && isNumeric(x[0]) && isNumeric(x[1]);
    156   }
    157 
    158   function _3d(x) {
    159     return x.length === 3 && isNumeric(x[0]) && isNumeric(x[1]) && isNumeric(x[2]);
    160   }
    161 
    162   function _4d(x) {
    163     return x.length === 4 && isNumeric(x[0]) && isNumeric(x[1]) && isNumeric(x[2]) && isNumeric(x[3]);
    164   }
    165 
    166   function _intersect2d(p1a, p1b, p2a, p2b) {
    167     var o1 = p1a;
    168     var o2 = p2a;
    169     var d1 = subtract(o1, p1b);
    170     var d2 = subtract(o2, p2b);
    171     var det = subtract(multiplyScalar(d1[0], d2[1]), multiplyScalar(d2[0], d1[1]));
    172     if (isZero(det)) return null;
    173 
    174     if (smaller(abs(det), config.epsilon)) {
    175       return null;
    176     }
    177 
    178     var d20o11 = multiplyScalar(d2[0], o1[1]);
    179     var d21o10 = multiplyScalar(d2[1], o1[0]);
    180     var d20o21 = multiplyScalar(d2[0], o2[1]);
    181     var d21o20 = multiplyScalar(d2[1], o2[0]);
    182     var t = divideScalar(addScalar(subtract(subtract(d20o11, d21o10), d20o21), d21o20), det);
    183     return add(multiply(d1, t), o1);
    184   }
    185 
    186   function _intersect3dHelper(a, b, c, d, e, f, g, h, i, j, k, l) {
    187     // (a - b)*(c - d) + (e - f)*(g - h) + (i - j)*(k - l)
    188     var add1 = multiplyScalar(subtract(a, b), subtract(c, d));
    189     var add2 = multiplyScalar(subtract(e, f), subtract(g, h));
    190     var add3 = multiplyScalar(subtract(i, j), subtract(k, l));
    191     return addScalar(addScalar(add1, add2), add3);
    192   }
    193 
    194   function _intersect3d(x1, y1, z1, x2, y2, z2, x3, y3, z3, x4, y4, z4) {
    195     var d1343 = _intersect3dHelper(x1, x3, x4, x3, y1, y3, y4, y3, z1, z3, z4, z3);
    196 
    197     var d4321 = _intersect3dHelper(x4, x3, x2, x1, y4, y3, y2, y1, z4, z3, z2, z1);
    198 
    199     var d1321 = _intersect3dHelper(x1, x3, x2, x1, y1, y3, y2, y1, z1, z3, z2, z1);
    200 
    201     var d4343 = _intersect3dHelper(x4, x3, x4, x3, y4, y3, y4, y3, z4, z3, z4, z3);
    202 
    203     var d2121 = _intersect3dHelper(x2, x1, x2, x1, y2, y1, y2, y1, z2, z1, z2, z1);
    204 
    205     var numerator = subtract(multiplyScalar(d1343, d4321), multiplyScalar(d1321, d4343));
    206     var denominator = subtract(multiplyScalar(d2121, d4343), multiplyScalar(d4321, d4321));
    207     if (isZero(denominator)) return null;
    208     var ta = divideScalar(numerator, denominator);
    209     var tb = divideScalar(addScalar(d1343, multiplyScalar(ta, d4321)), d4343);
    210     var pax = addScalar(x1, multiplyScalar(ta, subtract(x2, x1)));
    211     var pay = addScalar(y1, multiplyScalar(ta, subtract(y2, y1)));
    212     var paz = addScalar(z1, multiplyScalar(ta, subtract(z2, z1)));
    213     var pbx = addScalar(x3, multiplyScalar(tb, subtract(x4, x3)));
    214     var pby = addScalar(y3, multiplyScalar(tb, subtract(y4, y3)));
    215     var pbz = addScalar(z3, multiplyScalar(tb, subtract(z4, z3)));
    216 
    217     if (equalScalar(pax, pbx) && equalScalar(pay, pby) && equalScalar(paz, pbz)) {
    218       return [pax, pay, paz];
    219     } else {
    220       return null;
    221     }
    222   }
    223 
    224   function _intersectLinePlane(x1, y1, z1, x2, y2, z2, x, y, z, c) {
    225     var x1x = multiplyScalar(x1, x);
    226     var x2x = multiplyScalar(x2, x);
    227     var y1y = multiplyScalar(y1, y);
    228     var y2y = multiplyScalar(y2, y);
    229     var z1z = multiplyScalar(z1, z);
    230     var z2z = multiplyScalar(z2, z);
    231     var numerator = subtract(subtract(subtract(c, x1x), y1y), z1z);
    232     var denominator = subtract(subtract(subtract(addScalar(addScalar(x2x, y2y), z2z), x1x), y1y), z1z);
    233     var t = divideScalar(numerator, denominator);
    234     var px = addScalar(x1, multiplyScalar(t, subtract(x2, x1)));
    235     var py = addScalar(y1, multiplyScalar(t, subtract(y2, y1)));
    236     var pz = addScalar(z1, multiplyScalar(t, subtract(z2, z1)));
    237     return [px, py, pz]; // TODO: Add cases when line is parallel to the plane:
    238     //       (a) no intersection,
    239     //       (b) line contained in plane
    240   }
    241 });
    242 exports.createIntersect = createIntersect;