import Cartesian2 from './Cartesian2.js';
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import Cartesian3 from './Cartesian3.js';
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import Check from './Check.js';
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import defined from './defined.js';
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import CesiumMath from './Math.js';
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var scratchCartesian1 = new Cartesian3();
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var scratchCartesian2 = new Cartesian3();
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var scratchCartesian3 = new Cartesian3();
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/**
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* Computes the barycentric coordinates for a point with respect to a triangle.
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*
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* @exports barycentricCoordinates
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*
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* @param {Cartesian2|Cartesian3} point The point to test.
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* @param {Cartesian2|Cartesian3} p0 The first point of the triangle, corresponding to the barycentric x-axis.
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* @param {Cartesian2|Cartesian3} p1 The second point of the triangle, corresponding to the barycentric y-axis.
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* @param {Cartesian2|Cartesian3} p2 The third point of the triangle, corresponding to the barycentric z-axis.
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* @param {Cartesian3} [result] The object onto which to store the result.
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* @returns {Cartesian3} The modified result parameter or a new Cartesian3 instance if one was not provided.
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*
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* @example
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* // Returns Cartesian3.UNIT_X
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* var p = new Cesium.Cartesian3(-1.0, 0.0, 0.0);
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* var b = Cesium.barycentricCoordinates(p,
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* new Cesium.Cartesian3(-1.0, 0.0, 0.0),
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* new Cesium.Cartesian3( 1.0, 0.0, 0.0),
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* new Cesium.Cartesian3( 0.0, 1.0, 1.0));
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*/
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function barycentricCoordinates(point, p0, p1, p2, result) {
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//>>includeStart('debug', pragmas.debug);
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Check.defined('point', point);
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Check.defined('p0', p0);
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Check.defined('p1', p1);
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Check.defined('p2', p2);
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//>>includeEnd('debug');
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if (!defined(result)) {
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result = new Cartesian3();
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}
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// Implementation based on http://www.blackpawn.com/texts/pointinpoly/default.html.
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var v0;
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var v1;
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var v2;
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var dot00;
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var dot01;
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var dot02;
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var dot11;
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var dot12;
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if(!defined(p0.z)) {
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if (Cartesian2.equalsEpsilon(point, p0, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_X, result);
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}
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if (Cartesian2.equalsEpsilon(point, p1, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_Y, result);
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}
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if (Cartesian2.equalsEpsilon(point, p2, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_Z, result);
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}
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v0 = Cartesian2.subtract(p1, p0, scratchCartesian1);
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v1 = Cartesian2.subtract(p2, p0, scratchCartesian2);
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v2 = Cartesian2.subtract(point, p0, scratchCartesian3);
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dot00 = Cartesian2.dot(v0, v0);
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dot01 = Cartesian2.dot(v0, v1);
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dot02 = Cartesian2.dot(v0, v2);
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dot11 = Cartesian2.dot(v1, v1);
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dot12 = Cartesian2.dot(v1, v2);
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} else {
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if (Cartesian3.equalsEpsilon(point, p0, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_X, result);
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}
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if (Cartesian3.equalsEpsilon(point, p1, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_Y, result);
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}
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if (Cartesian3.equalsEpsilon(point, p2, CesiumMath.EPSILON14)) {
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return Cartesian3.clone(Cartesian3.UNIT_Z, result);
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}
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v0 = Cartesian3.subtract(p1, p0, scratchCartesian1);
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v1 = Cartesian3.subtract(p2, p0, scratchCartesian2);
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v2 = Cartesian3.subtract(point, p0, scratchCartesian3);
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dot00 = Cartesian3.dot(v0, v0);
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dot01 = Cartesian3.dot(v0, v1);
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dot02 = Cartesian3.dot(v0, v2);
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dot11 = Cartesian3.dot(v1, v1);
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dot12 = Cartesian3.dot(v1, v2);
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}
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result.y = (dot11 * dot02 - dot01 * dot12);
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result.z = (dot00 * dot12 - dot01 * dot02);
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var q = dot00 * dot11 - dot01 * dot01;
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// This is done to avoid dividing by infinity causing a NaN
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if (result.y !== 0) {
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result.y /= q;
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}
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if (result.z !== 0) {
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result.z /= q;
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}
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result.x = 1.0 - result.y - result.z;
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return result;
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}
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export default barycentricCoordinates;
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