/** * 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/main/LICENSE.md for full licensing details. */ define(['exports', './Matrix2-265d9610', './when-4bbc8319', './RuntimeError-5b082e8f', './Transforms-8b90e17c', './ComponentDatatype-aad54330'], (function (exports, Matrix2, when, RuntimeError, Transforms, ComponentDatatype) { 'use strict'; /** * Defines functions for 2nd order polynomial functions of one variable with only real coefficients. * * @namespace QuadraticRealPolynomial */ const 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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } //>>includeEnd('debug'); const discriminant = b * b - 4.0 * a * c; return discriminant; }; function addWithCancellationCheck$1(left, right, tolerance) { const difference = left + right; if ( ComponentDatatype.CesiumMath.sign(left) !== ComponentDatatype.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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } //>>includeEnd('debug'); let 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]; } const cMagnitude = Math.abs(c); const aMagnitude = Math.abs(a); if ( cMagnitude < aMagnitude && cMagnitude / aMagnitude < ComponentDatatype.CesiumMath.EPSILON14 ) { // c ~= 0.0. // 2nd order monomial: a * x^2 = 0. return [0.0, 0.0]; } else if ( cMagnitude > aMagnitude && aMagnitude / cMagnitude < ComponentDatatype.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. const 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 const b2 = b * b; const four_ac = 4.0 * a * c; const radicand = addWithCancellationCheck$1(b2, -four_ac, ComponentDatatype.CesiumMath.EPSILON14); if (radicand < 0.0) { // Both roots are complex. return []; } const q = -0.5 * addWithCancellationCheck$1( b, ComponentDatatype.CesiumMath.sign(b) * Math.sqrt(radicand), ComponentDatatype.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. * * @namespace CubicRealPolynomial */ const 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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } if (typeof d !== "number") { throw new RuntimeError.DeveloperError("d is a required number."); } //>>includeEnd('debug'); const a2 = a * a; const b2 = b * b; const c2 = c * c; const d2 = d * d; const 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) { const A = a; const B = b / 3.0; const C = c / 3.0; const D = d; const AC = A * C; const BD = B * D; const B2 = B * B; const C2 = C * C; const delta1 = A * C - B2; const delta2 = A * D - B * C; const delta3 = B * D - C2; const discriminant = 4.0 * delta1 * delta3 - delta2 * delta2; let temp; let temp1; if (discriminant < 0.0) { let ABar; let CBar; let 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; } const s = DBar < 0.0 ? -1.0 : 1.0; // This is not Math.Sign()! const temp0 = -s * Math.abs(ABar) * Math.sqrt(-discriminant); temp1 = -DBar + temp0; const x = temp1 / 2.0; const p = x < 0.0 ? -Math.pow(-x, 1.0 / 3.0) : Math.pow(x, 1.0 / 3.0); const 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)]; } const CBarA = delta1; const DBarA = -2.0 * B * delta1 + A * delta2; const CBarD = delta3; const DBarD = -D * delta2 + 2.0 * C * delta3; const squareRootOfDiscriminant = Math.sqrt(discriminant); const halfSquareRootOf3 = Math.sqrt(3.0) / 2.0; let theta = Math.abs(Math.atan2(A * squareRootOfDiscriminant, -DBarA) / 3.0); temp = 2.0 * Math.sqrt(-CBarA); let cosine = Math.cos(theta); temp1 = temp * cosine; let temp3 = temp * (-cosine / 2.0 - halfSquareRootOf3 * Math.sin(theta)); const numeratorLarge = temp1 + temp3 > 2.0 * B ? temp1 - B : temp3 - B; const denominatorLarge = A; const 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)); const numeratorSmall = -D; const denominatorSmall = temp1 + temp3 < 2.0 * C ? temp1 + C : temp3 + C; const root3 = numeratorSmall / denominatorSmall; const E = denominatorLarge * denominatorSmall; const F = -numeratorLarge * denominatorSmall - denominatorLarge * numeratorSmall; const G = numeratorLarge * numeratorSmall; const 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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } if (typeof d !== "number") { throw new RuntimeError.DeveloperError("d is a required number."); } //>>includeEnd('debug'); let roots; let 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; const 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. * * @namespace QuarticRealPolynomial */ const 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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } if (typeof d !== "number") { throw new RuntimeError.DeveloperError("d is a required number."); } if (typeof e !== "number") { throw new RuntimeError.DeveloperError("e is a required number."); } //>>includeEnd('debug'); const a2 = a * a; const a3 = a2 * a; const b2 = b * b; const b3 = b2 * b; const c2 = c * c; const c3 = c2 * c; const d2 = d * d; const d3 = d2 * d; const e2 = e * e; const e3 = e2 * e; const 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) { const a3Squared = a3 * a3; const p = a2 - (3.0 * a3Squared) / 8.0; const q = a1 - (a2 * a3) / 2.0 + (a3Squared * a3) / 8.0; const 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. const cubicRoots = CubicRealPolynomial.computeRealRoots( 1.0, 2.0 * p, p * p - 4.0 * r, -q * q ); if (cubicRoots.length > 0) { const temp = -a3 / 4.0; // Use the largest positive root. const hSquared = cubicRoots[cubicRoots.length - 1]; if (Math.abs(hSquared) < ComponentDatatype.CesiumMath.EPSILON14) { // y^4 + p y^2 + r = 0. const roots = QuadraticRealPolynomial.computeRealRoots(1.0, p, r); if (roots.length === 2) { const root0 = roots[0]; const root1 = roots[1]; let y; if (root0 >= 0.0 && root1 >= 0.0) { const y0 = Math.sqrt(root0); const 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) { const h = Math.sqrt(hSquared); const m = (p + hSquared - q / h) / 2.0; const n = (p + hSquared + q / h) / 2.0; // Now solve the two quadratic factors: (y^2 + h y + m)(y^2 - h y + n); const roots1 = QuadraticRealPolynomial.computeRealRoots(1.0, h, m); const 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) { const a1Squared = a1 * a1; const a2Squared = a2 * a2; const a3Squared = a3 * a3; const p = -2.0 * a2; const q = a1 * a3 + a2Squared - 4.0 * a0; const r = a3Squared * a0 - a1 * a2 * a3 + a1Squared; const cubicRoots = CubicRealPolynomial.computeRealRoots(1.0, p, q, r); if (cubicRoots.length > 0) { // Use the most positive root const y = cubicRoots[0]; const temp = a2 - y; const tempSquared = temp * temp; const g1 = a3 / 2.0; const h1 = temp / 2.0; const m = tempSquared - 4.0 * a0; const mError = tempSquared + 4.0 * Math.abs(a0); const n = a3Squared - 4.0 * y; const nError = a3Squared + 4.0 * Math.abs(y); let g2; let h2; if (y < 0.0 || m * nError < n * mError) { const squareRootOfN = Math.sqrt(n); g2 = squareRootOfN / 2.0; h2 = squareRootOfN === 0.0 ? 0.0 : (a3 * h1 - a1) / squareRootOfN; } else { const squareRootOfM = Math.sqrt(m); g2 = squareRootOfM === 0.0 ? 0.0 : (a3 * h1 - a1) / squareRootOfM; h2 = squareRootOfM / 2.0; } let G; let g; if (g1 === 0.0 && g2 === 0.0) { G = 0.0; g = 0.0; } else if (ComponentDatatype.CesiumMath.sign(g1) === ComponentDatatype.CesiumMath.sign(g2)) { G = g1 + g2; g = y / G; } else { g = g1 - g2; G = y / g; } let H; let h; if (h1 === 0.0 && h2 === 0.0) { H = 0.0; h = 0.0; } else if (ComponentDatatype.CesiumMath.sign(h1) === ComponentDatatype.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); const roots1 = QuadraticRealPolynomial.computeRealRoots(1.0, G, H); const 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 RuntimeError.DeveloperError("a is a required number."); } if (typeof b !== "number") { throw new RuntimeError.DeveloperError("b is a required number."); } if (typeof c !== "number") { throw new RuntimeError.DeveloperError("c is a required number."); } if (typeof d !== "number") { throw new RuntimeError.DeveloperError("d is a required number."); } if (typeof e !== "number") { throw new RuntimeError.DeveloperError("e is a required number."); } //>>includeEnd('debug'); if (Math.abs(a) < ComponentDatatype.CesiumMath.EPSILON15) { return CubicRealPolynomial.computeRealRoots(b, c, d, e); } const a3 = b / a; const a2 = c / a; const a1 = d / a; const a0 = e / a; let 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 = Matrix2.Cartesian3.clone(when.defaultValue(direction, Matrix2.Cartesian3.ZERO)); if (!Matrix2.Cartesian3.equals(direction, Matrix2.Cartesian3.ZERO)) { Matrix2.Cartesian3.normalize(direction, direction); } /** * The origin of the ray. * @type {Cartesian3} * @default {@link Cartesian3.ZERO} */ this.origin = Matrix2.Cartesian3.clone(when.defaultValue(origin, Matrix2.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 = Matrix2.Cartesian3.clone(ray.origin); result.direction = Matrix2.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. * const intersection = Cesium.IntersectionTests.rayEllipsoid(ray, ellipsoid); * const point = Cesium.Ray.getPoint(ray, intersection.start); */ Ray.getPoint = function (ray, t, result) { //>>includeStart('debug', pragmas.debug); RuntimeError.Check.typeOf.object("ray", ray); RuntimeError.Check.typeOf.number("t", t); //>>includeEnd('debug'); if (!when.defined(result)) { result = new Matrix2.Cartesian3(); } result = Matrix2.Cartesian3.multiplyByScalar(ray.direction, t, result); return Matrix2.Cartesian3.add(ray.origin, result, result); }; /** * Functions for computing the intersection between geometries such as rays, planes, triangles, and ellipsoids. * * @namespace IntersectionTests */ const 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 RuntimeError.DeveloperError("ray is required."); } if (!when.defined(plane)) { throw new RuntimeError.DeveloperError("plane is required."); } //>>includeEnd('debug'); if (!when.defined(result)) { result = new Matrix2.Cartesian3(); } const origin = ray.origin; const direction = ray.direction; const normal = plane.normal; const denominator = Matrix2.Cartesian3.dot(normal, direction); if (Math.abs(denominator) < ComponentDatatype.CesiumMath.EPSILON15) { // Ray is parallel to plane. The ray may be in the polygon's plane. return undefined; } const t = (-plane.distance - Matrix2.Cartesian3.dot(normal, origin)) / denominator; if (t < 0) { return undefined; } result = Matrix2.Cartesian3.multiplyByScalar(direction, t, result); return Matrix2.Cartesian3.add(origin, result, result); }; const scratchEdge0 = new Matrix2.Cartesian3(); const scratchEdge1 = new Matrix2.Cartesian3(); const scratchPVec = new Matrix2.Cartesian3(); const scratchTVec = new Matrix2.Cartesian3(); const scratchQVec = new Matrix2.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 true, 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 RuntimeError.DeveloperError("ray is required."); } if (!when.defined(p0)) { throw new RuntimeError.DeveloperError("p0 is required."); } if (!when.defined(p1)) { throw new RuntimeError.DeveloperError("p1 is required."); } if (!when.defined(p2)) { throw new RuntimeError.DeveloperError("p2 is required."); } //>>includeEnd('debug'); cullBackFaces = when.defaultValue(cullBackFaces, false); const origin = ray.origin; const direction = ray.direction; const edge0 = Matrix2.Cartesian3.subtract(p1, p0, scratchEdge0); const edge1 = Matrix2.Cartesian3.subtract(p2, p0, scratchEdge1); const p = Matrix2.Cartesian3.cross(direction, edge1, scratchPVec); const det = Matrix2.Cartesian3.dot(edge0, p); let tvec; let q; let u; let v; let t; if (cullBackFaces) { if (det < ComponentDatatype.CesiumMath.EPSILON6) { return undefined; } tvec = Matrix2.Cartesian3.subtract(origin, p0, scratchTVec); u = Matrix2.Cartesian3.dot(tvec, p); if (u < 0.0 || u > det) { return undefined; } q = Matrix2.Cartesian3.cross(tvec, edge0, scratchQVec); v = Matrix2.Cartesian3.dot(direction, q); if (v < 0.0 || u + v > det) { return undefined; } t = Matrix2.Cartesian3.dot(edge1, q) / det; } else { if (Math.abs(det) < ComponentDatatype.CesiumMath.EPSILON6) { return undefined; } const invDet = 1.0 / det; tvec = Matrix2.Cartesian3.subtract(origin, p0, scratchTVec); u = Matrix2.Cartesian3.dot(tvec, p) * invDet; if (u < 0.0 || u > 1.0) { return undefined; } q = Matrix2.Cartesian3.cross(tvec, edge0, scratchQVec); v = Matrix2.Cartesian3.dot(direction, q) * invDet; if (v < 0.0 || u + v > 1.0) { return undefined; } t = Matrix2.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 true, 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 Cartesian3 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 ) { const t = IntersectionTests.rayTriangleParametric( ray, p0, p1, p2, cullBackFaces ); if (!when.defined(t) || t < 0.0) { return undefined; } if (!when.defined(result)) { result = new Matrix2.Cartesian3(); } Matrix2.Cartesian3.multiplyByScalar(ray.direction, t, result); return Matrix2.Cartesian3.add(ray.origin, result, result); }; const 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 true, 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 Cartesian3 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 RuntimeError.DeveloperError("v0 is required."); } if (!when.defined(v1)) { throw new RuntimeError.DeveloperError("v1 is required."); } if (!when.defined(p0)) { throw new RuntimeError.DeveloperError("p0 is required."); } if (!when.defined(p1)) { throw new RuntimeError.DeveloperError("p1 is required."); } if (!when.defined(p2)) { throw new RuntimeError.DeveloperError("p2 is required."); } //>>includeEnd('debug'); const ray = scratchLineSegmentTriangleRay; Matrix2.Cartesian3.clone(v0, ray.origin); Matrix2.Cartesian3.subtract(v1, v0, ray.direction); Matrix2.Cartesian3.normalize(ray.direction, ray.direction); const t = IntersectionTests.rayTriangleParametric( ray, p0, p1, p2, cullBackFaces ); if (!when.defined(t) || t < 0.0 || t > Matrix2.Cartesian3.distance(v0, v1)) { return undefined; } if (!when.defined(result)) { result = new Matrix2.Cartesian3(); } Matrix2.Cartesian3.multiplyByScalar(ray.direction, t, result); return Matrix2.Cartesian3.add(ray.origin, result, result); }; function solveQuadratic(a, b, c, result) { const det = b * b - 4.0 * a * c; if (det < 0.0) { return undefined; } else if (det > 0.0) { const denom = 1.0 / (2.0 * a); const disc = Math.sqrt(det); const root0 = (-b + disc) * denom; const root1 = (-b - disc) * denom; if (root0 < root1) { result.root0 = root0; result.root1 = root1; } else { result.root0 = root1; result.root1 = root0; } return result; } const root = -b / (2.0 * a); if (root === 0.0) { return undefined; } result.root0 = result.root1 = root; return result; } const raySphereRoots = { root0: 0.0, root1: 0.0, }; function raySphere(ray, sphere, result) { if (!when.defined(result)) { result = new Transforms.Interval(); } const origin = ray.origin; const direction = ray.direction; const center = sphere.center; const radiusSquared = sphere.radius * sphere.radius; const diff = Matrix2.Cartesian3.subtract(origin, center, scratchPVec); const a = Matrix2.Cartesian3.dot(direction, direction); const b = 2.0 * Matrix2.Cartesian3.dot(direction, diff); const c = Matrix2.Cartesian3.magnitudeSquared(diff) - radiusSquared; const 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 RuntimeError.DeveloperError("ray is required."); } if (!when.defined(sphere)) { throw new RuntimeError.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; }; const 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 RuntimeError.DeveloperError("p0 is required."); } if (!when.defined(p1)) { throw new RuntimeError.DeveloperError("p1 is required."); } if (!when.defined(sphere)) { throw new RuntimeError.DeveloperError("sphere is required."); } //>>includeEnd('debug'); const ray = scratchLineSegmentRay; Matrix2.Cartesian3.clone(p0, ray.origin); const direction = Matrix2.Cartesian3.subtract(p1, p0, ray.direction); const maxT = Matrix2.Cartesian3.magnitude(direction); Matrix2.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; }; const scratchQ = new Matrix2.Cartesian3(); const scratchW = new Matrix2.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 RuntimeError.DeveloperError("ray is required."); } if (!when.defined(ellipsoid)) { throw new RuntimeError.DeveloperError("ellipsoid is required."); } //>>includeEnd('debug'); const inverseRadii = ellipsoid.oneOverRadii; const q = Matrix2.Cartesian3.multiplyComponents(inverseRadii, ray.origin, scratchQ); const w = Matrix2.Cartesian3.multiplyComponents( inverseRadii, ray.direction, scratchW ); const q2 = Matrix2.Cartesian3.magnitudeSquared(q); const qw = Matrix2.Cartesian3.dot(q, w); let 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. const qw2 = qw * qw; difference = q2 - 1.0; // Positively valued. w2 = Matrix2.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. const root0 = temp / w2; const root1 = difference / temp; if (root0 < root1) { return new Transforms.Interval(root0, root1); } return { start: root1, stop: root0, }; } // qw2 == product. Repeated roots (2 intersections). const root = Math.sqrt(difference / w2); return new Transforms.Interval(root, root); } else if (q2 < 1.0) { // Inside ellipsoid (2 intersections). difference = q2 - 1.0; // Negatively valued. w2 = Matrix2.Cartesian3.magnitudeSquared(w); product = w2 * difference; // Negatively valued. discriminant = qw * qw - product; temp = -qw + Math.sqrt(discriminant); // Positively valued. return new Transforms.Interval(0.0, temp / w2); } // q2 == 1.0. On ellipsoid. if (qw < 0.0) { // Looking inward. w2 = Matrix2.Cartesian3.magnitudeSquared(w); return new Transforms.Interval(0.0, -qw / w2); } // qw >= 0.0. Looking outward or tangent. return undefined; }; function addWithCancellationCheck(left, right, tolerance) { const difference = left + right; if ( ComponentDatatype.CesiumMath.sign(left) !== ComponentDatatype.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) { const xSquared = x * x; const wSquared = w * w; const l2 = (A[Matrix2.Matrix3.COLUMN1ROW1] - A[Matrix2.Matrix3.COLUMN2ROW2]) * wSquared; const l1 = w * (x * addWithCancellationCheck( A[Matrix2.Matrix3.COLUMN1ROW0], A[Matrix2.Matrix3.COLUMN0ROW1], ComponentDatatype.CesiumMath.EPSILON15 ) + b.y); const l0 = A[Matrix2.Matrix3.COLUMN0ROW0] * xSquared + A[Matrix2.Matrix3.COLUMN2ROW2] * wSquared + x * b.x + c; const r1 = wSquared * addWithCancellationCheck( A[Matrix2.Matrix3.COLUMN2ROW1], A[Matrix2.Matrix3.COLUMN1ROW2], ComponentDatatype.CesiumMath.EPSILON15 ); const r0 = w * (x * addWithCancellationCheck(A[Matrix2.Matrix3.COLUMN2ROW0], A[Matrix2.Matrix3.COLUMN0ROW2]) + b.z); let cosines; const solutions = []; if (r0 === 0.0 && r1 === 0.0) { cosines = QuadraticRealPolynomial.computeRealRoots(l2, l1, l0); if (cosines.length === 0) { return solutions; } const cosine0 = cosines[0]; const sine0 = Math.sqrt(Math.max(1.0 - cosine0 * cosine0, 0.0)); solutions.push(new Matrix2.Cartesian3(x, w * cosine0, w * -sine0)); solutions.push(new Matrix2.Cartesian3(x, w * cosine0, w * sine0)); if (cosines.length === 2) { const cosine1 = cosines[1]; const sine1 = Math.sqrt(Math.max(1.0 - cosine1 * cosine1, 0.0)); solutions.push(new Matrix2.Cartesian3(x, w * cosine1, w * -sine1)); solutions.push(new Matrix2.Cartesian3(x, w * cosine1, w * sine1)); } return solutions; } const r0Squared = r0 * r0; const r1Squared = r1 * r1; const l2Squared = l2 * l2; const r0r1 = r0 * r1; const c4 = l2Squared + r1Squared; const c3 = 2.0 * (l1 * l2 + r0r1); const c2 = 2.0 * l0 * l2 + l1 * l1 - r1Squared + r0Squared; const c1 = 2.0 * (l0 * l1 - r0r1); const 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); const length = cosines.length; if (length === 0) { return solutions; } for (let i = 0; i < length; ++i) { const cosine = cosines[i]; const cosineSquared = cosine * cosine; const sineSquared = Math.max(1.0 - cosineSquared, 0.0); const sine = Math.sqrt(sineSquared); //const left = l2 * cosineSquared + l1 * cosine + l0; let left; if (ComponentDatatype.CesiumMath.sign(l2) === ComponentDatatype.CesiumMath.sign(l0)) { left = addWithCancellationCheck( l2 * cosineSquared + l0, l1 * cosine, ComponentDatatype.CesiumMath.EPSILON12 ); } else if (ComponentDatatype.CesiumMath.sign(l0) === ComponentDatatype.CesiumMath.sign(l1 * cosine)) { left = addWithCancellationCheck( l2 * cosineSquared, l1 * cosine + l0, ComponentDatatype.CesiumMath.EPSILON12 ); } else { left = addWithCancellationCheck( l2 * cosineSquared + l1 * cosine, l0, ComponentDatatype.CesiumMath.EPSILON12 ); } const right = addWithCancellationCheck( r1 * cosine, r0, ComponentDatatype.CesiumMath.EPSILON15 ); const product = left * right; if (product < 0.0) { solutions.push(new Matrix2.Cartesian3(x, w * cosine, w * sine)); } else if (product > 0.0) { solutions.push(new Matrix2.Cartesian3(x, w * cosine, w * -sine)); } else if (sine !== 0.0) { solutions.push(new Matrix2.Cartesian3(x, w * cosine, w * -sine)); solutions.push(new Matrix2.Cartesian3(x, w * cosine, w * sine)); ++i; } else { solutions.push(new Matrix2.Cartesian3(x, w * cosine, w * sine)); } } return solutions; } const firstAxisScratch = new Matrix2.Cartesian3(); const secondAxisScratch = new Matrix2.Cartesian3(); const thirdAxisScratch = new Matrix2.Cartesian3(); const referenceScratch = new Matrix2.Cartesian3(); const bCart = new Matrix2.Cartesian3(); const bScratch = new Matrix2.Matrix3(); const btScratch = new Matrix2.Matrix3(); const diScratch = new Matrix2.Matrix3(); const dScratch = new Matrix2.Matrix3(); const cScratch = new Matrix2.Matrix3(); const tempMatrix = new Matrix2.Matrix3(); const aScratch = new Matrix2.Matrix3(); const sScratch = new Matrix2.Cartesian3(); const closestScratch = new Matrix2.Cartesian3(); const surfPointScratch = new Matrix2.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 RuntimeError.DeveloperError("ray is required."); } if (!when.defined(ellipsoid)) { throw new RuntimeError.DeveloperError("ellipsoid is required."); } //>>includeEnd('debug'); const position = ray.origin; const direction = ray.direction; if (!Matrix2.Cartesian3.equals(position, Matrix2.Cartesian3.ZERO)) { const normal = ellipsoid.geodeticSurfaceNormal(position, firstAxisScratch); if (Matrix2.Cartesian3.dot(direction, normal) >= 0.0) { // The location provided is the closest point in altitude return position; } } const intersects = when.defined(this.rayEllipsoid(ray, ellipsoid)); // Compute the scaled direction vector. const f = ellipsoid.transformPositionToScaledSpace( direction, firstAxisScratch ); // Constructs a basis from the unit scaled direction vector. Construct its rotation and transpose. const firstAxis = Matrix2.Cartesian3.normalize(f, f); const reference = Matrix2.Cartesian3.mostOrthogonalAxis(f, referenceScratch); const secondAxis = Matrix2.Cartesian3.normalize( Matrix2.Cartesian3.cross(reference, firstAxis, secondAxisScratch), secondAxisScratch ); const thirdAxis = Matrix2.Cartesian3.normalize( Matrix2.Cartesian3.cross(firstAxis, secondAxis, thirdAxisScratch), thirdAxisScratch ); const 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; const B_T = Matrix2.Matrix3.transpose(B, btScratch); // Get the scaling matrix and its inverse. const D_I = Matrix2.Matrix3.fromScale(ellipsoid.radii, diScratch); const D = Matrix2.Matrix3.fromScale(ellipsoid.oneOverRadii, dScratch); const 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; const temp = Matrix2.Matrix3.multiply( Matrix2.Matrix3.multiply(B_T, D, tempMatrix), C, tempMatrix ); const A = Matrix2.Matrix3.multiply( Matrix2.Matrix3.multiply(temp, D_I, aScratch), B, aScratch ); const b = Matrix2.Matrix3.multiplyByVector(temp, position, bCart); // Solve for the solutions to the expression in standard form: const solutions = quadraticVectorExpression( A, Matrix2.Cartesian3.negate(b, firstAxisScratch), 0.0, 0.0, 1.0 ); let s; let altitude; const length = solutions.length; if (length > 0) { let closest = Matrix2.Cartesian3.clone(Matrix2.Cartesian3.ZERO, closestScratch); let maximumValue = Number.NEGATIVE_INFINITY; for (let i = 0; i < length; ++i) { s = Matrix2.Matrix3.multiplyByVector( D_I, Matrix2.Matrix3.multiplyByVector(B, solutions[i], sScratch), sScratch ); const v = Matrix2.Cartesian3.normalize( Matrix2.Cartesian3.subtract(s, position, referenceScratch), referenceScratch ); const dotProduct = Matrix2.Cartesian3.dot(v, direction); if (dotProduct > maximumValue) { maximumValue = dotProduct; closest = Matrix2.Cartesian3.clone(s, closest); } } const surfacePoint = ellipsoid.cartesianToCartographic( closest, surfPointScratch ); maximumValue = ComponentDatatype.CesiumMath.clamp(maximumValue, 0.0, 1.0); altitude = Matrix2.Cartesian3.magnitude( Matrix2.Cartesian3.subtract(closest, position, referenceScratch) ) * Math.sqrt(1.0 - maximumValue * maximumValue); altitude = intersects ? -altitude : altitude; surfacePoint.height = altitude; return ellipsoid.cartographicToCartesian(surfacePoint, new Matrix2.Cartesian3()); } return undefined; }; const lineSegmentPlaneDifference = new Matrix2.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 * const origin = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883); * const normal = ellipsoid.geodeticSurfaceNormal(origin); * const plane = Cesium.Plane.fromPointNormal(origin, normal); * * const p0 = new Cesium.Cartesian3(...); * const p1 = new Cesium.Cartesian3(...); * * // find the intersection of the line segment from p0 to p1 and the tangent plane at origin. * const intersection = Cesium.IntersectionTests.lineSegmentPlane(p0, p1, plane); */ IntersectionTests.lineSegmentPlane = function ( endPoint0, endPoint1, plane, result ) { //>>includeStart('debug', pragmas.debug); if (!when.defined(endPoint0)) { throw new RuntimeError.DeveloperError("endPoint0 is required."); } if (!when.defined(endPoint1)) { throw new RuntimeError.DeveloperError("endPoint1 is required."); } if (!when.defined(plane)) { throw new RuntimeError.DeveloperError("plane is required."); } //>>includeEnd('debug'); if (!when.defined(result)) { result = new Matrix2.Cartesian3(); } const difference = Matrix2.Cartesian3.subtract( endPoint1, endPoint0, lineSegmentPlaneDifference ); const normal = plane.normal; const nDotDiff = Matrix2.Cartesian3.dot(normal, difference); // check if the segment and plane are parallel if (Math.abs(nDotDiff) < ComponentDatatype.CesiumMath.EPSILON6) { return undefined; } const nDotP0 = Matrix2.Cartesian3.dot(normal, endPoint0); const 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) Matrix2.Cartesian3.multiplyByScalar(difference, t, result); Matrix2.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 positions and indices, which are arrays that represent three triangles that do not cross the plane. (Undefined if no intersection exists) * * @example * const origin = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883); * const normal = ellipsoid.geodeticSurfaceNormal(origin); * const plane = Cesium.Plane.fromPointNormal(origin, normal); * * const p0 = new Cesium.Cartesian3(...); * const p1 = new Cesium.Cartesian3(...); * const p2 = new Cesium.Cartesian3(...); * * // convert the triangle composed of points (p0, p1, p2) to three triangles that don't cross the plane * const 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 RuntimeError.DeveloperError("p0, p1, p2, and plane are required."); } //>>includeEnd('debug'); const planeNormal = plane.normal; const planeD = plane.distance; const p0Behind = Matrix2.Cartesian3.dot(planeNormal, p0) + planeD < 0.0; const p1Behind = Matrix2.Cartesian3.dot(planeNormal, p1) + planeD < 0.0; const p2Behind = Matrix2.Cartesian3.dot(planeNormal, p2) + planeD < 0.0; // Given these dots products, the calls to lineSegmentPlaneIntersection // always have defined results. let numBehind = 0; numBehind += p0Behind ? 1 : 0; numBehind += p1Behind ? 1 : 0; numBehind += p2Behind ? 1 : 0; let u1, u2; if (numBehind === 1 || numBehind === 2) { u1 = new Matrix2.Cartesian3(); u2 = new Matrix2.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; })); //# sourceMappingURL=IntersectionTests-596e31ec.js.map