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/**
* Cesium - https://github.com/CesiumGS/cesium
*
* Copyright 2011-2020 Cesium Contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Columbus View (Pat. Pend.)
*
* Portions licensed separately.
* See https://github.com/CesiumGS/cesium/blob/master/LICENSE.md for full licensing details.
*/
define(['exports', './when-8d13db60', './Check-70bec281', './Math-61ede240', './Cartographic-f2a06374', './BoundingSphere-d018a565'], function (exports, when, Check, _Math, Cartographic, BoundingSphere) { 'use strict';
/**
* Defines functions for 2nd order polynomial functions of one variable with only real coefficients.
*
* @exports QuadraticRealPolynomial
*/
var QuadraticRealPolynomial = {};
/**
* Provides the discriminant of the quadratic equation from the supplied coefficients.
*
* @param {Number} a The coefficient of the 2nd order monomial.
* @param {Number} b The coefficient of the 1st order monomial.
* @param {Number} c The coefficient of the 0th order monomial.
* @returns {Number} The value of the discriminant.
*/
QuadraticRealPolynomial.computeDiscriminant = function(a, b, c) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
//>>includeEnd('debug');
var discriminant = b * b - 4.0 * a * c;
return discriminant;
};
function addWithCancellationCheck(left, right, tolerance) {
var difference = left + right;
if ((_Math.CesiumMath.sign(left) !== _Math.CesiumMath.sign(right)) &&
Math.abs(difference / Math.max(Math.abs(left), Math.abs(right))) < tolerance) {
return 0.0;
}
return difference;
}
/**
* Provides the real valued roots of the quadratic polynomial with the provided coefficients.
*
* @param {Number} a The coefficient of the 2nd order monomial.
* @param {Number} b The coefficient of the 1st order monomial.
* @param {Number} c The coefficient of the 0th order monomial.
* @returns {Number[]} The real valued roots.
*/
QuadraticRealPolynomial.computeRealRoots = function(a, b, c) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
//>>includeEnd('debug');
var ratio;
if (a === 0.0) {
if (b === 0.0) {
// Constant function: c = 0.
return [];
}
// Linear function: b * x + c = 0.
return [-c / b];
} else if (b === 0.0) {
if (c === 0.0) {
// 2nd order monomial: a * x^2 = 0.
return [0.0, 0.0];
}
var cMagnitude = Math.abs(c);
var aMagnitude = Math.abs(a);
if ((cMagnitude < aMagnitude) && (cMagnitude / aMagnitude < _Math.CesiumMath.EPSILON14)) { // c ~= 0.0.
// 2nd order monomial: a * x^2 = 0.
return [0.0, 0.0];
} else if ((cMagnitude > aMagnitude) && (aMagnitude / cMagnitude < _Math.CesiumMath.EPSILON14)) { // a ~= 0.0.
// Constant function: c = 0.
return [];
}
// a * x^2 + c = 0
ratio = -c / a;
if (ratio < 0.0) {
// Both roots are complex.
return [];
}
// Both roots are real.
var root = Math.sqrt(ratio);
return [-root, root];
} else if (c === 0.0) {
// a * x^2 + b * x = 0
ratio = -b / a;
if (ratio < 0.0) {
return [ratio, 0.0];
}
return [0.0, ratio];
}
// a * x^2 + b * x + c = 0
var b2 = b * b;
var four_ac = 4.0 * a * c;
var radicand = addWithCancellationCheck(b2, -four_ac, _Math.CesiumMath.EPSILON14);
if (radicand < 0.0) {
// Both roots are complex.
return [];
}
var q = -0.5 * addWithCancellationCheck(b, _Math.CesiumMath.sign(b) * Math.sqrt(radicand), _Math.CesiumMath.EPSILON14);
if (b > 0.0) {
return [q / a, c / q];
}
return [c / q, q / a];
};
/**
* Defines functions for 3rd order polynomial functions of one variable with only real coefficients.
*
* @exports CubicRealPolynomial
*/
var CubicRealPolynomial = {};
/**
* Provides the discriminant of the cubic equation from the supplied coefficients.
*
* @param {Number} a The coefficient of the 3rd order monomial.
* @param {Number} b The coefficient of the 2nd order monomial.
* @param {Number} c The coefficient of the 1st order monomial.
* @param {Number} d The coefficient of the 0th order monomial.
* @returns {Number} The value of the discriminant.
*/
CubicRealPolynomial.computeDiscriminant = function(a, b, c, d) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
if (typeof d !== 'number') {
throw new Check.DeveloperError('d is a required number.');
}
//>>includeEnd('debug');
var a2 = a * a;
var b2 = b * b;
var c2 = c * c;
var d2 = d * d;
var discriminant = 18.0 * a * b * c * d + b2 * c2 - 27.0 * a2 * d2 - 4.0 * (a * c2 * c + b2 * b * d);
return discriminant;
};
function computeRealRoots(a, b, c, d) {
var A = a;
var B = b / 3.0;
var C = c / 3.0;
var D = d;
var AC = A * C;
var BD = B * D;
var B2 = B * B;
var C2 = C * C;
var delta1 = A * C - B2;
var delta2 = A * D - B * C;
var delta3 = B * D - C2;
var discriminant = 4.0 * delta1 * delta3 - delta2 * delta2;
var temp;
var temp1;
if (discriminant < 0.0) {
var ABar;
var CBar;
var DBar;
if (B2 * BD >= AC * C2) {
ABar = A;
CBar = delta1;
DBar = -2.0 * B * delta1 + A * delta2;
} else {
ABar = D;
CBar = delta3;
DBar = -D * delta2 + 2.0 * C * delta3;
}
var s = (DBar < 0.0) ? -1.0 : 1.0; // This is not Math.Sign()!
var temp0 = -s * Math.abs(ABar) * Math.sqrt(-discriminant);
temp1 = -DBar + temp0;
var x = temp1 / 2.0;
var p = x < 0.0 ? -Math.pow(-x, 1.0 / 3.0) : Math.pow(x, 1.0 / 3.0);
var q = (temp1 === temp0) ? -p : -CBar / p;
temp = (CBar <= 0.0) ? p + q : -DBar / (p * p + q * q + CBar);
if (B2 * BD >= AC * C2) {
return [(temp - B) / A];
}
return [-D / (temp + C)];
}
var CBarA = delta1;
var DBarA = -2.0 * B * delta1 + A * delta2;
var CBarD = delta3;
var DBarD = -D * delta2 + 2.0 * C * delta3;
var squareRootOfDiscriminant = Math.sqrt(discriminant);
var halfSquareRootOf3 = Math.sqrt(3.0) / 2.0;
var theta = Math.abs(Math.atan2(A * squareRootOfDiscriminant, -DBarA) / 3.0);
temp = 2.0 * Math.sqrt(-CBarA);
var cosine = Math.cos(theta);
temp1 = temp * cosine;
var temp3 = temp * (-cosine / 2.0 - halfSquareRootOf3 * Math.sin(theta));
var numeratorLarge = (temp1 + temp3 > 2.0 * B) ? temp1 - B : temp3 - B;
var denominatorLarge = A;
var root1 = numeratorLarge / denominatorLarge;
theta = Math.abs(Math.atan2(D * squareRootOfDiscriminant, -DBarD) / 3.0);
temp = 2.0 * Math.sqrt(-CBarD);
cosine = Math.cos(theta);
temp1 = temp * cosine;
temp3 = temp * (-cosine / 2.0 - halfSquareRootOf3 * Math.sin(theta));
var numeratorSmall = -D;
var denominatorSmall = (temp1 + temp3 < 2.0 * C) ? temp1 + C : temp3 + C;
var root3 = numeratorSmall / denominatorSmall;
var E = denominatorLarge * denominatorSmall;
var F = -numeratorLarge * denominatorSmall - denominatorLarge * numeratorSmall;
var G = numeratorLarge * numeratorSmall;
var root2 = (C * F - B * G) / (-B * F + C * E);
if (root1 <= root2) {
if (root1 <= root3) {
if (root2 <= root3) {
return [root1, root2, root3];
}
return [root1, root3, root2];
}
return [root3, root1, root2];
}
if (root1 <= root3) {
return [root2, root1, root3];
}
if (root2 <= root3) {
return [root2, root3, root1];
}
return [root3, root2, root1];
}
/**
* Provides the real valued roots of the cubic polynomial with the provided coefficients.
*
* @param {Number} a The coefficient of the 3rd order monomial.
* @param {Number} b The coefficient of the 2nd order monomial.
* @param {Number} c The coefficient of the 1st order monomial.
* @param {Number} d The coefficient of the 0th order monomial.
* @returns {Number[]} The real valued roots.
*/
CubicRealPolynomial.computeRealRoots = function(a, b, c, d) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
if (typeof d !== 'number') {
throw new Check.DeveloperError('d is a required number.');
}
//>>includeEnd('debug');
var roots;
var ratio;
if (a === 0.0) {
// Quadratic function: b * x^2 + c * x + d = 0.
return QuadraticRealPolynomial.computeRealRoots(b, c, d);
} else if (b === 0.0) {
if (c === 0.0) {
if (d === 0.0) {
// 3rd order monomial: a * x^3 = 0.
return [0.0, 0.0, 0.0];
}
// a * x^3 + d = 0
ratio = -d / a;
var root = (ratio < 0.0) ? -Math.pow(-ratio, 1.0 / 3.0) : Math.pow(ratio, 1.0 / 3.0);
return [root, root, root];
} else if (d === 0.0) {
// x * (a * x^2 + c) = 0.
roots = QuadraticRealPolynomial.computeRealRoots(a, 0, c);
// Return the roots in ascending order.
if (roots.Length === 0) {
return [0.0];
}
return [roots[0], 0.0, roots[1]];
}
// Deflated cubic polynomial: a * x^3 + c * x + d= 0.
return computeRealRoots(a, 0, c, d);
} else if (c === 0.0) {
if (d === 0.0) {
// x^2 * (a * x + b) = 0.
ratio = -b / a;
if (ratio < 0.0) {
return [ratio, 0.0, 0.0];
}
return [0.0, 0.0, ratio];
}
// a * x^3 + b * x^2 + d = 0.
return computeRealRoots(a, b, 0, d);
} else if (d === 0.0) {
// x * (a * x^2 + b * x + c) = 0
roots = QuadraticRealPolynomial.computeRealRoots(a, b, c);
// Return the roots in ascending order.
if (roots.length === 0) {
return [0.0];
} else if (roots[1] <= 0.0) {
return [roots[0], roots[1], 0.0];
} else if (roots[0] >= 0.0) {
return [0.0, roots[0], roots[1]];
}
return [roots[0], 0.0, roots[1]];
}
return computeRealRoots(a, b, c, d);
};
/**
* Defines functions for 4th order polynomial functions of one variable with only real coefficients.
*
* @exports QuarticRealPolynomial
*/
var QuarticRealPolynomial = {};
/**
* Provides the discriminant of the quartic equation from the supplied coefficients.
*
* @param {Number} a The coefficient of the 4th order monomial.
* @param {Number} b The coefficient of the 3rd order monomial.
* @param {Number} c The coefficient of the 2nd order monomial.
* @param {Number} d The coefficient of the 1st order monomial.
* @param {Number} e The coefficient of the 0th order monomial.
* @returns {Number} The value of the discriminant.
*/
QuarticRealPolynomial.computeDiscriminant = function(a, b, c, d, e) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
if (typeof d !== 'number') {
throw new Check.DeveloperError('d is a required number.');
}
if (typeof e !== 'number') {
throw new Check.DeveloperError('e is a required number.');
}
//>>includeEnd('debug');
var a2 = a * a;
var a3 = a2 * a;
var b2 = b * b;
var b3 = b2 * b;
var c2 = c * c;
var c3 = c2 * c;
var d2 = d * d;
var d3 = d2 * d;
var e2 = e * e;
var e3 = e2 * e;
var discriminant = (b2 * c2 * d2 - 4.0 * b3 * d3 - 4.0 * a * c3 * d2 + 18 * a * b * c * d3 - 27.0 * a2 * d2 * d2 + 256.0 * a3 * e3) +
e * (18.0 * b3 * c * d - 4.0 * b2 * c3 + 16.0 * a * c2 * c2 - 80.0 * a * b * c2 * d - 6.0 * a * b2 * d2 + 144.0 * a2 * c * d2) +
e2 * (144.0 * a * b2 * c - 27.0 * b2 * b2 - 128.0 * a2 * c2 - 192.0 * a2 * b * d);
return discriminant;
};
function original(a3, a2, a1, a0) {
var a3Squared = a3 * a3;
var p = a2 - 3.0 * a3Squared / 8.0;
var q = a1 - a2 * a3 / 2.0 + a3Squared * a3 / 8.0;
var r = a0 - a1 * a3 / 4.0 + a2 * a3Squared / 16.0 - 3.0 * a3Squared * a3Squared / 256.0;
// Find the roots of the cubic equations: h^6 + 2 p h^4 + (p^2 - 4 r) h^2 - q^2 = 0.
var cubicRoots = CubicRealPolynomial.computeRealRoots(1.0, 2.0 * p, p * p - 4.0 * r, -q * q);
if (cubicRoots.length > 0) {
var temp = -a3 / 4.0;
// Use the largest positive root.
var hSquared = cubicRoots[cubicRoots.length - 1];
if (Math.abs(hSquared) < _Math.CesiumMath.EPSILON14) {
// y^4 + p y^2 + r = 0.
var roots = QuadraticRealPolynomial.computeRealRoots(1.0, p, r);
if (roots.length === 2) {
var root0 = roots[0];
var root1 = roots[1];
var y;
if (root0 >= 0.0 && root1 >= 0.0) {
var y0 = Math.sqrt(root0);
var y1 = Math.sqrt(root1);
return [temp - y1, temp - y0, temp + y0, temp + y1];
} else if (root0 >= 0.0 && root1 < 0.0) {
y = Math.sqrt(root0);
return [temp - y, temp + y];
} else if (root0 < 0.0 && root1 >= 0.0) {
y = Math.sqrt(root1);
return [temp - y, temp + y];
}
}
return [];
} else if (hSquared > 0.0) {
var h = Math.sqrt(hSquared);
var m = (p + hSquared - q / h) / 2.0;
var n = (p + hSquared + q / h) / 2.0;
// Now solve the two quadratic factors: (y^2 + h y + m)(y^2 - h y + n);
var roots1 = QuadraticRealPolynomial.computeRealRoots(1.0, h, m);
var roots2 = QuadraticRealPolynomial.computeRealRoots(1.0, -h, n);
if (roots1.length !== 0) {
roots1[0] += temp;
roots1[1] += temp;
if (roots2.length !== 0) {
roots2[0] += temp;
roots2[1] += temp;
if (roots1[1] <= roots2[0]) {
return [roots1[0], roots1[1], roots2[0], roots2[1]];
} else if (roots2[1] <= roots1[0]) {
return [roots2[0], roots2[1], roots1[0], roots1[1]];
} else if (roots1[0] >= roots2[0] && roots1[1] <= roots2[1]) {
return [roots2[0], roots1[0], roots1[1], roots2[1]];
} else if (roots2[0] >= roots1[0] && roots2[1] <= roots1[1]) {
return [roots1[0], roots2[0], roots2[1], roots1[1]];
} else if (roots1[0] > roots2[0] && roots1[0] < roots2[1]) {
return [roots2[0], roots1[0], roots2[1], roots1[1]];
}
return [roots1[0], roots2[0], roots1[1], roots2[1]];
}
return roots1;
}
if (roots2.length !== 0) {
roots2[0] += temp;
roots2[1] += temp;
return roots2;
}
return [];
}
}
return [];
}
function neumark(a3, a2, a1, a0) {
var a1Squared = a1 * a1;
var a2Squared = a2 * a2;
var a3Squared = a3 * a3;
var p = -2.0 * a2;
var q = a1 * a3 + a2Squared - 4.0 * a0;
var r = a3Squared * a0 - a1 * a2 * a3 + a1Squared;
var cubicRoots = CubicRealPolynomial.computeRealRoots(1.0, p, q, r);
if (cubicRoots.length > 0) {
// Use the most positive root
var y = cubicRoots[0];
var temp = (a2 - y);
var tempSquared = temp * temp;
var g1 = a3 / 2.0;
var h1 = temp / 2.0;
var m = tempSquared - 4.0 * a0;
var mError = tempSquared + 4.0 * Math.abs(a0);
var n = a3Squared - 4.0 * y;
var nError = a3Squared + 4.0 * Math.abs(y);
var g2;
var h2;
if (y < 0.0 || (m * nError < n * mError)) {
var squareRootOfN = Math.sqrt(n);
g2 = squareRootOfN / 2.0;
h2 = squareRootOfN === 0.0 ? 0.0 : (a3 * h1 - a1) / squareRootOfN;
} else {
var squareRootOfM = Math.sqrt(m);
g2 = squareRootOfM === 0.0 ? 0.0 : (a3 * h1 - a1) / squareRootOfM;
h2 = squareRootOfM / 2.0;
}
var G;
var g;
if (g1 === 0.0 && g2 === 0.0) {
G = 0.0;
g = 0.0;
} else if (_Math.CesiumMath.sign(g1) === _Math.CesiumMath.sign(g2)) {
G = g1 + g2;
g = y / G;
} else {
g = g1 - g2;
G = y / g;
}
var H;
var h;
if (h1 === 0.0 && h2 === 0.0) {
H = 0.0;
h = 0.0;
} else if (_Math.CesiumMath.sign(h1) === _Math.CesiumMath.sign(h2)) {
H = h1 + h2;
h = a0 / H;
} else {
h = h1 - h2;
H = a0 / h;
}
// Now solve the two quadratic factors: (y^2 + G y + H)(y^2 + g y + h);
var roots1 = QuadraticRealPolynomial.computeRealRoots(1.0, G, H);
var roots2 = QuadraticRealPolynomial.computeRealRoots(1.0, g, h);
if (roots1.length !== 0) {
if (roots2.length !== 0) {
if (roots1[1] <= roots2[0]) {
return [roots1[0], roots1[1], roots2[0], roots2[1]];
} else if (roots2[1] <= roots1[0]) {
return [roots2[0], roots2[1], roots1[0], roots1[1]];
} else if (roots1[0] >= roots2[0] && roots1[1] <= roots2[1]) {
return [roots2[0], roots1[0], roots1[1], roots2[1]];
} else if (roots2[0] >= roots1[0] && roots2[1] <= roots1[1]) {
return [roots1[0], roots2[0], roots2[1], roots1[1]];
} else if (roots1[0] > roots2[0] && roots1[0] < roots2[1]) {
return [roots2[0], roots1[0], roots2[1], roots1[1]];
}
return [roots1[0], roots2[0], roots1[1], roots2[1]];
}
return roots1;
}
if (roots2.length !== 0) {
return roots2;
}
}
return [];
}
/**
* Provides the real valued roots of the quartic polynomial with the provided coefficients.
*
* @param {Number} a The coefficient of the 4th order monomial.
* @param {Number} b The coefficient of the 3rd order monomial.
* @param {Number} c The coefficient of the 2nd order monomial.
* @param {Number} d The coefficient of the 1st order monomial.
* @param {Number} e The coefficient of the 0th order monomial.
* @returns {Number[]} The real valued roots.
*/
QuarticRealPolynomial.computeRealRoots = function(a, b, c, d, e) {
//>>includeStart('debug', pragmas.debug);
if (typeof a !== 'number') {
throw new Check.DeveloperError('a is a required number.');
}
if (typeof b !== 'number') {
throw new Check.DeveloperError('b is a required number.');
}
if (typeof c !== 'number') {
throw new Check.DeveloperError('c is a required number.');
}
if (typeof d !== 'number') {
throw new Check.DeveloperError('d is a required number.');
}
if (typeof e !== 'number') {
throw new Check.DeveloperError('e is a required number.');
}
//>>includeEnd('debug');
if (Math.abs(a) < _Math.CesiumMath.EPSILON15) {
return CubicRealPolynomial.computeRealRoots(b, c, d, e);
}
var a3 = b / a;
var a2 = c / a;
var a1 = d / a;
var a0 = e / a;
var k = (a3 < 0.0) ? 1 : 0;
k += (a2 < 0.0) ? k + 1 : k;
k += (a1 < 0.0) ? k + 1 : k;
k += (a0 < 0.0) ? k + 1 : k;
switch (k) {
case 0:
return original(a3, a2, a1, a0);
case 1:
return neumark(a3, a2, a1, a0);
case 2:
return neumark(a3, a2, a1, a0);
case 3:
return original(a3, a2, a1, a0);
case 4:
return original(a3, a2, a1, a0);
case 5:
return neumark(a3, a2, a1, a0);
case 6:
return original(a3, a2, a1, a0);
case 7:
return original(a3, a2, a1, a0);
case 8:
return neumark(a3, a2, a1, a0);
case 9:
return original(a3, a2, a1, a0);
case 10:
return original(a3, a2, a1, a0);
case 11:
return neumark(a3, a2, a1, a0);
case 12:
return original(a3, a2, a1, a0);
case 13:
return original(a3, a2, a1, a0);
case 14:
return original(a3, a2, a1, a0);
case 15:
return original(a3, a2, a1, a0);
default:
return undefined;
}
};
/**
* Represents a ray that extends infinitely from the provided origin in the provided direction.
* @alias Ray
* @constructor
*
* @param {Cartesian3} [origin=Cartesian3.ZERO] The origin of the ray.
* @param {Cartesian3} [direction=Cartesian3.ZERO] The direction of the ray.
*/
function Ray(origin, direction) {
direction = Cartographic.Cartesian3.clone(when.defaultValue(direction, Cartographic.Cartesian3.ZERO));
if (!Cartographic.Cartesian3.equals(direction, Cartographic.Cartesian3.ZERO)) {
Cartographic.Cartesian3.normalize(direction, direction);
}
/**
* The origin of the ray.
* @type {Cartesian3}
* @default {@link Cartesian3.ZERO}
*/
this.origin = Cartographic.Cartesian3.clone(when.defaultValue(origin, Cartographic.Cartesian3.ZERO));
/**
* The direction of the ray.
* @type {Cartesian3}
*/
this.direction = direction;
}
/**
* Duplicates a Ray instance.
*
* @param {Ray} ray The ray to duplicate.
* @param {Ray} [result] The object onto which to store the result.
* @returns {Ray} The modified result parameter or a new Ray instance if one was not provided. (Returns undefined if ray is undefined)
*/
Ray.clone = function(ray, result) {
if (!when.defined(ray)) {
return undefined;
}
if (!when.defined(result)) {
return new Ray(ray.origin, ray.direction);
}
result.origin = Cartographic.Cartesian3.clone(ray.origin);
result.direction = Cartographic.Cartesian3.clone(ray.direction);
return result;
};
/**
* Computes the point along the ray given by r(t) = o + t*d,
* where o is the origin of the ray and d is the direction.
*
* @param {Ray} ray The ray.
* @param {Number} t A scalar value.
* @param {Cartesian3} [result] The object in which the result will be stored.
* @returns {Cartesian3} The modified result parameter, or a new instance if none was provided.
*
* @example
* //Get the first intersection point of a ray and an ellipsoid.
* var intersection = Cesium.IntersectionTests.rayEllipsoid(ray, ellipsoid);
* var point = Cesium.Ray.getPoint(ray, intersection.start);
*/
Ray.getPoint = function(ray, t, result) {
//>>includeStart('debug', pragmas.debug);
Check.Check.typeOf.object('ray', ray);
Check.Check.typeOf.number('t', t);
//>>includeEnd('debug');
if (!when.defined(result)) {
result = new Cartographic.Cartesian3();
}
result = Cartographic.Cartesian3.multiplyByScalar(ray.direction, t, result);
return Cartographic.Cartesian3.add(ray.origin, result, result);
};
/**
* Functions for computing the intersection between geometries such as rays, planes, triangles, and ellipsoids.
*
* @exports IntersectionTests
* @namespace
*/
var IntersectionTests = {};
/**
* Computes the intersection of a ray and a plane.
*
* @param {Ray} ray The ray.
* @param {Plane} plane The plane.
* @param {Cartesian3} [result] The object onto which to store the result.
* @returns {Cartesian3} The intersection point or undefined if there is no intersections.
*/
IntersectionTests.rayPlane = function(ray, plane, result) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(ray)) {
throw new Check.DeveloperError('ray is required.');
}
if (!when.defined(plane)) {
throw new Check.DeveloperError('plane is required.');
}
//>>includeEnd('debug');
if (!when.defined(result)) {
result = new Cartographic.Cartesian3();
}
var origin = ray.origin;
var direction = ray.direction;
var normal = plane.normal;
var denominator = Cartographic.Cartesian3.dot(normal, direction);
if (Math.abs(denominator) < _Math.CesiumMath.EPSILON15) {
// Ray is parallel to plane. The ray may be in the polygon's plane.
return undefined;
}
var t = (-plane.distance - Cartographic.Cartesian3.dot(normal, origin)) / denominator;
if (t < 0) {
return undefined;
}
result = Cartographic.Cartesian3.multiplyByScalar(direction, t, result);
return Cartographic.Cartesian3.add(origin, result, result);
};
var scratchEdge0 = new Cartographic.Cartesian3();
var scratchEdge1 = new Cartographic.Cartesian3();
var scratchPVec = new Cartographic.Cartesian3();
var scratchTVec = new Cartographic.Cartesian3();
var scratchQVec = new Cartographic.Cartesian3();
/**
* Computes the intersection of a ray and a triangle as a parametric distance along the input ray. The result is negative when the triangle is behind the ray.
*
* Implements {@link https://cadxfem.org/inf/Fast%20MinimumStorage%20RayTriangle%20Intersection.pdf|
* Fast Minimum Storage Ray/Triangle Intersection} by Tomas Moller and Ben Trumbore.
*
* @memberof IntersectionTests
*
* @param {Ray} ray The ray.
* @param {Cartesian3} p0 The first vertex of the triangle.
* @param {Cartesian3} p1 The second vertex of the triangle.
* @param {Cartesian3} p2 The third vertex of the triangle.
* @param {Boolean} [cullBackFaces=false] If <code>true</code>, will only compute an intersection with the front face of the triangle
* and return undefined for intersections with the back face.
* @returns {Number} The intersection as a parametric distance along the ray, or undefined if there is no intersection.
*/
IntersectionTests.rayTriangleParametric = function(ray, p0, p1, p2, cullBackFaces) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(ray)) {
throw new Check.DeveloperError('ray is required.');
}
if (!when.defined(p0)) {
throw new Check.DeveloperError('p0 is required.');
}
if (!when.defined(p1)) {
throw new Check.DeveloperError('p1 is required.');
}
if (!when.defined(p2)) {
throw new Check.DeveloperError('p2 is required.');
}
//>>includeEnd('debug');
cullBackFaces = when.defaultValue(cullBackFaces, false);
var origin = ray.origin;
var direction = ray.direction;
var edge0 = Cartographic.Cartesian3.subtract(p1, p0, scratchEdge0);
var edge1 = Cartographic.Cartesian3.subtract(p2, p0, scratchEdge1);
var p = Cartographic.Cartesian3.cross(direction, edge1, scratchPVec);
var det = Cartographic.Cartesian3.dot(edge0, p);
var tvec;
var q;
var u;
var v;
var t;
if (cullBackFaces) {
if (det < _Math.CesiumMath.EPSILON6) {
return undefined;
}
tvec = Cartographic.Cartesian3.subtract(origin, p0, scratchTVec);
u = Cartographic.Cartesian3.dot(tvec, p);
if (u < 0.0 || u > det) {
return undefined;
}
q = Cartographic.Cartesian3.cross(tvec, edge0, scratchQVec);
v = Cartographic.Cartesian3.dot(direction, q);
if (v < 0.0 || u + v > det) {
return undefined;
}
t = Cartographic.Cartesian3.dot(edge1, q) / det;
} else {
if (Math.abs(det) < _Math.CesiumMath.EPSILON6) {
return undefined;
}
var invDet = 1.0 / det;
tvec = Cartographic.Cartesian3.subtract(origin, p0, scratchTVec);
u = Cartographic.Cartesian3.dot(tvec, p) * invDet;
if (u < 0.0 || u > 1.0) {
return undefined;
}
q = Cartographic.Cartesian3.cross(tvec, edge0, scratchQVec);
v = Cartographic.Cartesian3.dot(direction, q) * invDet;
if (v < 0.0 || u + v > 1.0) {
return undefined;
}
t = Cartographic.Cartesian3.dot(edge1, q) * invDet;
}
return t;
};
/**
* Computes the intersection of a ray and a triangle as a Cartesian3 coordinate.
*
* Implements {@link https://cadxfem.org/inf/Fast%20MinimumStorage%20RayTriangle%20Intersection.pdf|
* Fast Minimum Storage Ray/Triangle Intersection} by Tomas Moller and Ben Trumbore.
*
* @memberof IntersectionTests
*
* @param {Ray} ray The ray.
* @param {Cartesian3} p0 The first vertex of the triangle.
* @param {Cartesian3} p1 The second vertex of the triangle.
* @param {Cartesian3} p2 The third vertex of the triangle.
* @param {Boolean} [cullBackFaces=false] If <code>true</code>, will only compute an intersection with the front face of the triangle
* and return undefined for intersections with the back face.
* @param {Cartesian3} [result] The <code>Cartesian3</code> onto which to store the result.
* @returns {Cartesian3} The intersection point or undefined if there is no intersections.
*/
IntersectionTests.rayTriangle = function(ray, p0, p1, p2, cullBackFaces, result) {
var t = IntersectionTests.rayTriangleParametric(ray, p0, p1, p2, cullBackFaces);
if (!when.defined(t) || t < 0.0) {
return undefined;
}
if (!when.defined(result)) {
result = new Cartographic.Cartesian3();
}
Cartographic.Cartesian3.multiplyByScalar(ray.direction, t, result);
return Cartographic.Cartesian3.add(ray.origin, result, result);
};
var scratchLineSegmentTriangleRay = new Ray();
/**
* Computes the intersection of a line segment and a triangle.
* @memberof IntersectionTests
*
* @param {Cartesian3} v0 The an end point of the line segment.
* @param {Cartesian3} v1 The other end point of the line segment.
* @param {Cartesian3} p0 The first vertex of the triangle.
* @param {Cartesian3} p1 The second vertex of the triangle.
* @param {Cartesian3} p2 The third vertex of the triangle.
* @param {Boolean} [cullBackFaces=false] If <code>true</code>, will only compute an intersection with the front face of the triangle
* and return undefined for intersections with the back face.
* @param {Cartesian3} [result] The <code>Cartesian3</code> onto which to store the result.
* @returns {Cartesian3} The intersection point or undefined if there is no intersections.
*/
IntersectionTests.lineSegmentTriangle = function(v0, v1, p0, p1, p2, cullBackFaces, result) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(v0)) {
throw new Check.DeveloperError('v0 is required.');
}
if (!when.defined(v1)) {
throw new Check.DeveloperError('v1 is required.');
}
if (!when.defined(p0)) {
throw new Check.DeveloperError('p0 is required.');
}
if (!when.defined(p1)) {
throw new Check.DeveloperError('p1 is required.');
}
if (!when.defined(p2)) {
throw new Check.DeveloperError('p2 is required.');
}
//>>includeEnd('debug');
var ray = scratchLineSegmentTriangleRay;
Cartographic.Cartesian3.clone(v0, ray.origin);
Cartographic.Cartesian3.subtract(v1, v0, ray.direction);
Cartographic.Cartesian3.normalize(ray.direction, ray.direction);
var t = IntersectionTests.rayTriangleParametric(ray, p0, p1, p2, cullBackFaces);
if (!when.defined(t) || t < 0.0 || t > Cartographic.Cartesian3.distance(v0, v1)) {
return undefined;
}
if (!when.defined(result)) {
result = new Cartographic.Cartesian3();
}
Cartographic.Cartesian3.multiplyByScalar(ray.direction, t, result);
return Cartographic.Cartesian3.add(ray.origin, result, result);
};
function solveQuadratic(a, b, c, result) {
var det = b * b - 4.0 * a * c;
if (det < 0.0) {
return undefined;
} else if (det > 0.0) {
var denom = 1.0 / (2.0 * a);
var disc = Math.sqrt(det);
var root0 = (-b + disc) * denom;
var root1 = (-b - disc) * denom;
if (root0 < root1) {
result.root0 = root0;
result.root1 = root1;
} else {
result.root0 = root1;
result.root1 = root0;
}
return result;
}
var root = -b / (2.0 * a);
if (root === 0.0) {
return undefined;
}
result.root0 = result.root1 = root;
return result;
}
var raySphereRoots = {
root0 : 0.0,
root1 : 0.0
};
function raySphere(ray, sphere, result) {
if (!when.defined(result)) {
result = new BoundingSphere.Interval();
}
var origin = ray.origin;
var direction = ray.direction;
var center = sphere.center;
var radiusSquared = sphere.radius * sphere.radius;
var diff = Cartographic.Cartesian3.subtract(origin, center, scratchPVec);
var a = Cartographic.Cartesian3.dot(direction, direction);
var b = 2.0 * Cartographic.Cartesian3.dot(direction, diff);
var c = Cartographic.Cartesian3.magnitudeSquared(diff) - radiusSquared;
var roots = solveQuadratic(a, b, c, raySphereRoots);
if (!when.defined(roots)) {
return undefined;
}
result.start = roots.root0;
result.stop = roots.root1;
return result;
}
/**
* Computes the intersection points of a ray with a sphere.
* @memberof IntersectionTests
*
* @param {Ray} ray The ray.
* @param {BoundingSphere} sphere The sphere.
* @param {Interval} [result] The result onto which to store the result.
* @returns {Interval} The interval containing scalar points along the ray or undefined if there are no intersections.
*/
IntersectionTests.raySphere = function(ray, sphere, result) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(ray)) {
throw new Check.DeveloperError('ray is required.');
}
if (!when.defined(sphere)) {
throw new Check.DeveloperError('sphere is required.');
}
//>>includeEnd('debug');
result = raySphere(ray, sphere, result);
if (!when.defined(result) || result.stop < 0.0) {
return undefined;
}
result.start = Math.max(result.start, 0.0);
return result;
};
var scratchLineSegmentRay = new Ray();
/**
* Computes the intersection points of a line segment with a sphere.
* @memberof IntersectionTests
*
* @param {Cartesian3} p0 An end point of the line segment.
* @param {Cartesian3} p1 The other end point of the line segment.
* @param {BoundingSphere} sphere The sphere.
* @param {Interval} [result] The result onto which to store the result.
* @returns {Interval} The interval containing scalar points along the ray or undefined if there are no intersections.
*/
IntersectionTests.lineSegmentSphere = function(p0, p1, sphere, result) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(p0)) {
throw new Check.DeveloperError('p0 is required.');
}
if (!when.defined(p1)) {
throw new Check.DeveloperError('p1 is required.');
}
if (!when.defined(sphere)) {
throw new Check.DeveloperError('sphere is required.');
}
//>>includeEnd('debug');
var ray = scratchLineSegmentRay;
Cartographic.Cartesian3.clone(p0, ray.origin);
var direction = Cartographic.Cartesian3.subtract(p1, p0, ray.direction);
var maxT = Cartographic.Cartesian3.magnitude(direction);
Cartographic.Cartesian3.normalize(direction, direction);
result = raySphere(ray, sphere, result);
if (!when.defined(result) || result.stop < 0.0 || result.start > maxT) {
return undefined;
}
result.start = Math.max(result.start, 0.0);
result.stop = Math.min(result.stop, maxT);
return result;
};
var scratchQ = new Cartographic.Cartesian3();
var scratchW = new Cartographic.Cartesian3();
/**
* Computes the intersection points of a ray with an ellipsoid.
*
* @param {Ray} ray The ray.
* @param {Ellipsoid} ellipsoid The ellipsoid.
* @returns {Interval} The interval containing scalar points along the ray or undefined if there are no intersections.
*/
IntersectionTests.rayEllipsoid = function(ray, ellipsoid) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(ray)) {
throw new Check.DeveloperError('ray is required.');
}
if (!when.defined(ellipsoid)) {
throw new Check.DeveloperError('ellipsoid is required.');
}
//>>includeEnd('debug');
var inverseRadii = ellipsoid.oneOverRadii;
var q = Cartographic.Cartesian3.multiplyComponents(inverseRadii, ray.origin, scratchQ);
var w = Cartographic.Cartesian3.multiplyComponents(inverseRadii, ray.direction, scratchW);
var q2 = Cartographic.Cartesian3.magnitudeSquared(q);
var qw = Cartographic.Cartesian3.dot(q, w);
var difference, w2, product, discriminant, temp;
if (q2 > 1.0) {
// Outside ellipsoid.
if (qw >= 0.0) {
// Looking outward or tangent (0 intersections).
return undefined;
}
// qw < 0.0.
var qw2 = qw * qw;
difference = q2 - 1.0; // Positively valued.
w2 = Cartographic.Cartesian3.magnitudeSquared(w);
product = w2 * difference;
if (qw2 < product) {
// Imaginary roots (0 intersections).
return undefined;
} else if (qw2 > product) {
// Distinct roots (2 intersections).
discriminant = qw * qw - product;
temp = -qw + Math.sqrt(discriminant); // Avoid cancellation.
var root0 = temp / w2;
var root1 = difference / temp;
if (root0 < root1) {
return new BoundingSphere.Interval(root0, root1);
}
return {
start : root1,
stop : root0
};
}
// qw2 == product. Repeated roots (2 intersections).
var root = Math.sqrt(difference / w2);
return new BoundingSphere.Interval(root, root);
} else if (q2 < 1.0) {
// Inside ellipsoid (2 intersections).
difference = q2 - 1.0; // Negatively valued.
w2 = Cartographic.Cartesian3.magnitudeSquared(w);
product = w2 * difference; // Negatively valued.
discriminant = qw * qw - product;
temp = -qw + Math.sqrt(discriminant); // Positively valued.
return new BoundingSphere.Interval(0.0, temp / w2);
}
// q2 == 1.0. On ellipsoid.
if (qw < 0.0) {
// Looking inward.
w2 = Cartographic.Cartesian3.magnitudeSquared(w);
return new BoundingSphere.Interval(0.0, -qw / w2);
}
// qw >= 0.0. Looking outward or tangent.
return undefined;
};
function addWithCancellationCheck$1(left, right, tolerance) {
var difference = left + right;
if ((_Math.CesiumMath.sign(left) !== _Math.CesiumMath.sign(right)) &&
Math.abs(difference / Math.max(Math.abs(left), Math.abs(right))) < tolerance) {
return 0.0;
}
return difference;
}
function quadraticVectorExpression(A, b, c, x, w) {
var xSquared = x * x;
var wSquared = w * w;
var l2 = (A[BoundingSphere.Matrix3.COLUMN1ROW1] - A[BoundingSphere.Matrix3.COLUMN2ROW2]) * wSquared;
var l1 = w * (x * addWithCancellationCheck$1(A[BoundingSphere.Matrix3.COLUMN1ROW0], A[BoundingSphere.Matrix3.COLUMN0ROW1], _Math.CesiumMath.EPSILON15) + b.y);
var l0 = (A[BoundingSphere.Matrix3.COLUMN0ROW0] * xSquared + A[BoundingSphere.Matrix3.COLUMN2ROW2] * wSquared) + x * b.x + c;
var r1 = wSquared * addWithCancellationCheck$1(A[BoundingSphere.Matrix3.COLUMN2ROW1], A[BoundingSphere.Matrix3.COLUMN1ROW2], _Math.CesiumMath.EPSILON15);
var r0 = w * (x * addWithCancellationCheck$1(A[BoundingSphere.Matrix3.COLUMN2ROW0], A[BoundingSphere.Matrix3.COLUMN0ROW2]) + b.z);
var cosines;
var solutions = [];
if (r0 === 0.0 && r1 === 0.0) {
cosines = QuadraticRealPolynomial.computeRealRoots(l2, l1, l0);
if (cosines.length === 0) {
return solutions;
}
var cosine0 = cosines[0];
var sine0 = Math.sqrt(Math.max(1.0 - cosine0 * cosine0, 0.0));
solutions.push(new Cartographic.Cartesian3(x, w * cosine0, w * -sine0));
solutions.push(new Cartographic.Cartesian3(x, w * cosine0, w * sine0));
if (cosines.length === 2) {
var cosine1 = cosines[1];
var sine1 = Math.sqrt(Math.max(1.0 - cosine1 * cosine1, 0.0));
solutions.push(new Cartographic.Cartesian3(x, w * cosine1, w * -sine1));
solutions.push(new Cartographic.Cartesian3(x, w * cosine1, w * sine1));
}
return solutions;
}
var r0Squared = r0 * r0;
var r1Squared = r1 * r1;
var l2Squared = l2 * l2;
var r0r1 = r0 * r1;
var c4 = l2Squared + r1Squared;
var c3 = 2.0 * (l1 * l2 + r0r1);
var c2 = 2.0 * l0 * l2 + l1 * l1 - r1Squared + r0Squared;
var c1 = 2.0 * (l0 * l1 - r0r1);
var c0 = l0 * l0 - r0Squared;
if (c4 === 0.0 && c3 === 0.0 && c2 === 0.0 && c1 === 0.0) {
return solutions;
}
cosines = QuarticRealPolynomial.computeRealRoots(c4, c3, c2, c1, c0);
var length = cosines.length;
if (length === 0) {
return solutions;
}
for ( var i = 0; i < length; ++i) {
var cosine = cosines[i];
var cosineSquared = cosine * cosine;
var sineSquared = Math.max(1.0 - cosineSquared, 0.0);
var sine = Math.sqrt(sineSquared);
//var left = l2 * cosineSquared + l1 * cosine + l0;
var left;
if (_Math.CesiumMath.sign(l2) === _Math.CesiumMath.sign(l0)) {
left = addWithCancellationCheck$1(l2 * cosineSquared + l0, l1 * cosine, _Math.CesiumMath.EPSILON12);
} else if (_Math.CesiumMath.sign(l0) === _Math.CesiumMath.sign(l1 * cosine)) {
left = addWithCancellationCheck$1(l2 * cosineSquared, l1 * cosine + l0, _Math.CesiumMath.EPSILON12);
} else {
left = addWithCancellationCheck$1(l2 * cosineSquared + l1 * cosine, l0, _Math.CesiumMath.EPSILON12);
}
var right = addWithCancellationCheck$1(r1 * cosine, r0, _Math.CesiumMath.EPSILON15);
var product = left * right;
if (product < 0.0) {
solutions.push(new Cartographic.Cartesian3(x, w * cosine, w * sine));
} else if (product > 0.0) {
solutions.push(new Cartographic.Cartesian3(x, w * cosine, w * -sine));
} else if (sine !== 0.0) {
solutions.push(new Cartographic.Cartesian3(x, w * cosine, w * -sine));
solutions.push(new Cartographic.Cartesian3(x, w * cosine, w * sine));
++i;
} else {
solutions.push(new Cartographic.Cartesian3(x, w * cosine, w * sine));
}
}
return solutions;
}
var firstAxisScratch = new Cartographic.Cartesian3();
var secondAxisScratch = new Cartographic.Cartesian3();
var thirdAxisScratch = new Cartographic.Cartesian3();
var referenceScratch = new Cartographic.Cartesian3();
var bCart = new Cartographic.Cartesian3();
var bScratch = new BoundingSphere.Matrix3();
var btScratch = new BoundingSphere.Matrix3();
var diScratch = new BoundingSphere.Matrix3();
var dScratch = new BoundingSphere.Matrix3();
var cScratch = new BoundingSphere.Matrix3();
var tempMatrix = new BoundingSphere.Matrix3();
var aScratch = new BoundingSphere.Matrix3();
var sScratch = new Cartographic.Cartesian3();
var closestScratch = new Cartographic.Cartesian3();
var surfPointScratch = new Cartographic.Cartographic();
/**
* Provides the point along the ray which is nearest to the ellipsoid.
*
* @param {Ray} ray The ray.
* @param {Ellipsoid} ellipsoid The ellipsoid.
* @returns {Cartesian3} The nearest planetodetic point on the ray.
*/
IntersectionTests.grazingAltitudeLocation = function(ray, ellipsoid) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(ray)) {
throw new Check.DeveloperError('ray is required.');
}
if (!when.defined(ellipsoid)) {
throw new Check.DeveloperError('ellipsoid is required.');
}
//>>includeEnd('debug');
var position = ray.origin;
var direction = ray.direction;
if (!Cartographic.Cartesian3.equals(position, Cartographic.Cartesian3.ZERO)) {
var normal = ellipsoid.geodeticSurfaceNormal(position, firstAxisScratch);
if (Cartographic.Cartesian3.dot(direction, normal) >= 0.0) { // The location provided is the closest point in altitude
return position;
}
}
var intersects = when.defined(this.rayEllipsoid(ray, ellipsoid));
// Compute the scaled direction vector.
var f = ellipsoid.transformPositionToScaledSpace(direction, firstAxisScratch);
// Constructs a basis from the unit scaled direction vector. Construct its rotation and transpose.
var firstAxis = Cartographic.Cartesian3.normalize(f, f);
var reference = Cartographic.Cartesian3.mostOrthogonalAxis(f, referenceScratch);
var secondAxis = Cartographic.Cartesian3.normalize(Cartographic.Cartesian3.cross(reference, firstAxis, secondAxisScratch), secondAxisScratch);
var thirdAxis = Cartographic.Cartesian3.normalize(Cartographic.Cartesian3.cross(firstAxis, secondAxis, thirdAxisScratch), thirdAxisScratch);
var B = bScratch;
B[0] = firstAxis.x;
B[1] = firstAxis.y;
B[2] = firstAxis.z;
B[3] = secondAxis.x;
B[4] = secondAxis.y;
B[5] = secondAxis.z;
B[6] = thirdAxis.x;
B[7] = thirdAxis.y;
B[8] = thirdAxis.z;
var B_T = BoundingSphere.Matrix3.transpose(B, btScratch);
// Get the scaling matrix and its inverse.
var D_I = BoundingSphere.Matrix3.fromScale(ellipsoid.radii, diScratch);
var D = BoundingSphere.Matrix3.fromScale(ellipsoid.oneOverRadii, dScratch);
var C = cScratch;
C[0] = 0.0;
C[1] = -direction.z;
C[2] = direction.y;
C[3] = direction.z;
C[4] = 0.0;
C[5] = -direction.x;
C[6] = -direction.y;
C[7] = direction.x;
C[8] = 0.0;
var temp = BoundingSphere.Matrix3.multiply(BoundingSphere.Matrix3.multiply(B_T, D, tempMatrix), C, tempMatrix);
var A = BoundingSphere.Matrix3.multiply(BoundingSphere.Matrix3.multiply(temp, D_I, aScratch), B, aScratch);
var b = BoundingSphere.Matrix3.multiplyByVector(temp, position, bCart);
// Solve for the solutions to the expression in standard form:
var solutions = quadraticVectorExpression(A, Cartographic.Cartesian3.negate(b, firstAxisScratch), 0.0, 0.0, 1.0);
var s;
var altitude;
var length = solutions.length;
if (length > 0) {
var closest = Cartographic.Cartesian3.clone(Cartographic.Cartesian3.ZERO, closestScratch);
var maximumValue = Number.NEGATIVE_INFINITY;
for ( var i = 0; i < length; ++i) {
s = BoundingSphere.Matrix3.multiplyByVector(D_I, BoundingSphere.Matrix3.multiplyByVector(B, solutions[i], sScratch), sScratch);
var v = Cartographic.Cartesian3.normalize(Cartographic.Cartesian3.subtract(s, position, referenceScratch), referenceScratch);
var dotProduct = Cartographic.Cartesian3.dot(v, direction);
if (dotProduct > maximumValue) {
maximumValue = dotProduct;
closest = Cartographic.Cartesian3.clone(s, closest);
}
}
var surfacePoint = ellipsoid.cartesianToCartographic(closest, surfPointScratch);
maximumValue = _Math.CesiumMath.clamp(maximumValue, 0.0, 1.0);
altitude = Cartographic.Cartesian3.magnitude(Cartographic.Cartesian3.subtract(closest, position, referenceScratch)) * Math.sqrt(1.0 - maximumValue * maximumValue);
altitude = intersects ? -altitude : altitude;
surfacePoint.height = altitude;
return ellipsoid.cartographicToCartesian(surfacePoint, new Cartographic.Cartesian3());
}
return undefined;
};
var lineSegmentPlaneDifference = new Cartographic.Cartesian3();
/**
* Computes the intersection of a line segment and a plane.
*
* @param {Cartesian3} endPoint0 An end point of the line segment.
* @param {Cartesian3} endPoint1 The other end point of the line segment.
* @param {Plane} plane The plane.
* @param {Cartesian3} [result] The object onto which to store the result.
* @returns {Cartesian3} The intersection point or undefined if there is no intersection.
*
* @example
* var origin = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883);
* var normal = ellipsoid.geodeticSurfaceNormal(origin);
* var plane = Cesium.Plane.fromPointNormal(origin, normal);
*
* var p0 = new Cesium.Cartesian3(...);
* var p1 = new Cesium.Cartesian3(...);
*
* // find the intersection of the line segment from p0 to p1 and the tangent plane at origin.
* var intersection = Cesium.IntersectionTests.lineSegmentPlane(p0, p1, plane);
*/
IntersectionTests.lineSegmentPlane = function(endPoint0, endPoint1, plane, result) {
//>>includeStart('debug', pragmas.debug);
if (!when.defined(endPoint0)) {
throw new Check.DeveloperError('endPoint0 is required.');
}
if (!when.defined(endPoint1)) {
throw new Check.DeveloperError('endPoint1 is required.');
}
if (!when.defined(plane)) {
throw new Check.DeveloperError('plane is required.');
}
//>>includeEnd('debug');
if (!when.defined(result)) {
result = new Cartographic.Cartesian3();
}
var difference = Cartographic.Cartesian3.subtract(endPoint1, endPoint0, lineSegmentPlaneDifference);
var normal = plane.normal;
var nDotDiff = Cartographic.Cartesian3.dot(normal, difference);
// check if the segment and plane are parallel
if (Math.abs(nDotDiff) < _Math.CesiumMath.EPSILON6) {
return undefined;
}
var nDotP0 = Cartographic.Cartesian3.dot(normal, endPoint0);
var t = -(plane.distance + nDotP0) / nDotDiff;
// intersection only if t is in [0, 1]
if (t < 0.0 || t > 1.0) {
return undefined;
}
// intersection is endPoint0 + t * (endPoint1 - endPoint0)
Cartographic.Cartesian3.multiplyByScalar(difference, t, result);
Cartographic.Cartesian3.add(endPoint0, result, result);
return result;
};
/**
* Computes the intersection of a triangle and a plane
*
* @param {Cartesian3} p0 First point of the triangle
* @param {Cartesian3} p1 Second point of the triangle
* @param {Cartesian3} p2 Third point of the triangle
* @param {Plane} plane Intersection plane
* @returns {Object} An object with properties <code>positions</code> and <code>indices</code>, which are arrays that represent three triangles that do not cross the plane. (Undefined if no intersection exists)
*
* @example
* var origin = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883);
* var normal = ellipsoid.geodeticSurfaceNormal(origin);
* var plane = Cesium.Plane.fromPointNormal(origin, normal);
*
* var p0 = new Cesium.Cartesian3(...);
* var p1 = new Cesium.Cartesian3(...);
* var p2 = new Cesium.Cartesian3(...);
*
* // convert the triangle composed of points (p0, p1, p2) to three triangles that don't cross the plane
* var triangles = Cesium.IntersectionTests.trianglePlaneIntersection(p0, p1, p2, plane);
*/
IntersectionTests.trianglePlaneIntersection = function(p0, p1, p2, plane) {
//>>includeStart('debug', pragmas.debug);
if ((!when.defined(p0)) ||
(!when.defined(p1)) ||
(!when.defined(p2)) ||
(!when.defined(plane))) {
throw new Check.DeveloperError('p0, p1, p2, and plane are required.');
}
//>>includeEnd('debug');
var planeNormal = plane.normal;
var planeD = plane.distance;
var p0Behind = (Cartographic.Cartesian3.dot(planeNormal, p0) + planeD) < 0.0;
var p1Behind = (Cartographic.Cartesian3.dot(planeNormal, p1) + planeD) < 0.0;
var p2Behind = (Cartographic.Cartesian3.dot(planeNormal, p2) + planeD) < 0.0;
// Given these dots products, the calls to lineSegmentPlaneIntersection
// always have defined results.
var numBehind = 0;
numBehind += p0Behind ? 1 : 0;
numBehind += p1Behind ? 1 : 0;
numBehind += p2Behind ? 1 : 0;
var u1, u2;
if (numBehind === 1 || numBehind === 2) {
u1 = new Cartographic.Cartesian3();
u2 = new Cartographic.Cartesian3();
}
if (numBehind === 1) {
if (p0Behind) {
IntersectionTests.lineSegmentPlane(p0, p1, plane, u1);
IntersectionTests.lineSegmentPlane(p0, p2, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
0, 3, 4,
// In front
1, 2, 4,
1, 4, 3
]
};
} else if (p1Behind) {
IntersectionTests.lineSegmentPlane(p1, p2, plane, u1);
IntersectionTests.lineSegmentPlane(p1, p0, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
1, 3, 4,
// In front
2, 0, 4,
2, 4, 3
]
};
} else if (p2Behind) {
IntersectionTests.lineSegmentPlane(p2, p0, plane, u1);
IntersectionTests.lineSegmentPlane(p2, p1, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
2, 3, 4,
// In front
0, 1, 4,
0, 4, 3
]
};
}
} else if (numBehind === 2) {
if (!p0Behind) {
IntersectionTests.lineSegmentPlane(p1, p0, plane, u1);
IntersectionTests.lineSegmentPlane(p2, p0, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
1, 2, 4,
1, 4, 3,
// In front
0, 3, 4
]
};
} else if (!p1Behind) {
IntersectionTests.lineSegmentPlane(p2, p1, plane, u1);
IntersectionTests.lineSegmentPlane(p0, p1, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
2, 0, 4,
2, 4, 3,
// In front
1, 3, 4
]
};
} else if (!p2Behind) {
IntersectionTests.lineSegmentPlane(p0, p2, plane, u1);
IntersectionTests.lineSegmentPlane(p1, p2, plane, u2);
return {
positions : [p0, p1, p2, u1, u2 ],
indices : [
// Behind
0, 1, 4,
0, 4, 3,
// In front
2, 3, 4
]
};
}
}
// if numBehind is 3, the triangle is completely behind the plane;
// otherwise, it is completely in front (numBehind is 0).
return undefined;
};
exports.IntersectionTests = IntersectionTests;
exports.Ray = Ray;
});