Cesium-Prequel/Source/Core/AxisAlignedBoundingBox.js

import Cartesian3 from "./Cartesian3.js";
import Check from "./Check.js";
import defaultValue from "./defaultValue.js";
import defined from "./defined.js";
import Intersect from "./Intersect.js";

/**
 * Creates an instance of an AxisAlignedBoundingBox from the minimum and maximum points along the x, y, and z axes.
 * @alias AxisAlignedBoundingBox
 * @constructor
 *
 * @param {Cartesian3} [minimum=Cartesian3.ZERO] The minimum point along the x, y, and z axes.
 * @param {Cartesian3} [maximum=Cartesian3.ZERO] The maximum point along the x, y, and z axes.
 * @param {Cartesian3} [center] The center of the box; automatically computed if not supplied.
 *
 * @see BoundingSphere
 * @see BoundingRectangle
 */
function AxisAlignedBoundingBox(minimum, maximum, center) {
  /**
   * The minimum point defining the bounding box.
   * @type {Cartesian3}
   * @default {@link Cartesian3.ZERO}
   */
  this.minimum = Cartesian3.clone(defaultValue(minimum, Cartesian3.ZERO));

  /**
   * The maximum point defining the bounding box.
   * @type {Cartesian3}
   * @default {@link Cartesian3.ZERO}
   */
  this.maximum = Cartesian3.clone(defaultValue(maximum, Cartesian3.ZERO));

  //If center was not defined, compute it.
  if (!defined(center)) {
    center = Cartesian3.midpoint(this.minimum, this.maximum, new Cartesian3());
  } else {
    center = Cartesian3.clone(center);
  }

  /**
   * The center point of the bounding box.
   * @type {Cartesian3}
   */
  this.center = center;
}

/**
 * Computes an instance of an AxisAlignedBoundingBox. The box is determined by
 * finding the points spaced the farthest apart on the x, y, and z axes.
 *
 * @param {Cartesian3[]} positions List of points that the bounding box will enclose.  Each point must have a <code>x</code>, <code>y</code>, and <code>z</code> properties.
 * @param {AxisAlignedBoundingBox} [result] The object onto which to store the result.
 * @returns {AxisAlignedBoundingBox} The modified result parameter or a new AxisAlignedBoundingBox instance if one was not provided.
 *
 * @example
 * // Compute an axis aligned bounding box enclosing two points.
 * var box = Cesium.AxisAlignedBoundingBox.fromPoints([new Cesium.Cartesian3(2, 0, 0), new Cesium.Cartesian3(-2, 0, 0)]);
 */
AxisAlignedBoundingBox.fromPoints = function (positions, result) {
  if (!defined(result)) {
    result = new AxisAlignedBoundingBox();
  }

  if (!defined(positions) || positions.length === 0) {
    result.minimum = Cartesian3.clone(Cartesian3.ZERO, result.minimum);
    result.maximum = Cartesian3.clone(Cartesian3.ZERO, result.maximum);
    result.center = Cartesian3.clone(Cartesian3.ZERO, result.center);
    return result;
  }

  var minimumX = positions[0].x;
  var minimumY = positions[0].y;
  var minimumZ = positions[0].z;

  var maximumX = positions[0].x;
  var maximumY = positions[0].y;
  var maximumZ = positions[0].z;

  var length = positions.length;
  for (var i = 1; i < length; i++) {
    var p = positions[i];
    var x = p.x;
    var y = p.y;
    var z = p.z;

    minimumX = Math.min(x, minimumX);
    maximumX = Math.max(x, maximumX);
    minimumY = Math.min(y, minimumY);
    maximumY = Math.max(y, maximumY);
    minimumZ = Math.min(z, minimumZ);
    maximumZ = Math.max(z, maximumZ);
  }

  var minimum = result.minimum;
  minimum.x = minimumX;
  minimum.y = minimumY;
  minimum.z = minimumZ;

  var maximum = result.maximum;
  maximum.x = maximumX;
  maximum.y = maximumY;
  maximum.z = maximumZ;

  result.center = Cartesian3.midpoint(minimum, maximum, result.center);

  return result;
};

/**
 * Duplicates a AxisAlignedBoundingBox instance.
 *
 * @param {AxisAlignedBoundingBox} box The bounding box to duplicate.
 * @param {AxisAlignedBoundingBox} [result] The object onto which to store the result.
 * @returns {AxisAlignedBoundingBox} The modified result parameter or a new AxisAlignedBoundingBox instance if none was provided. (Returns undefined if box is undefined)
 */
AxisAlignedBoundingBox.clone = function (box, result) {
  if (!defined(box)) {
    return undefined;
  }

  if (!defined(result)) {
    return new AxisAlignedBoundingBox(box.minimum, box.maximum, box.center);
  }

  result.minimum = Cartesian3.clone(box.minimum, result.minimum);
  result.maximum = Cartesian3.clone(box.maximum, result.maximum);
  result.center = Cartesian3.clone(box.center, result.center);
  return result;
};

/**
 * Compares the provided AxisAlignedBoundingBox componentwise and returns
 * <code>true</code> if they are equal, <code>false</code> otherwise.
 *
 * @param {AxisAlignedBoundingBox} [left] The first AxisAlignedBoundingBox.
 * @param {AxisAlignedBoundingBox} [right] The second AxisAlignedBoundingBox.
 * @returns {Boolean} <code>true</code> if left and right are equal, <code>false</code> otherwise.
 */
AxisAlignedBoundingBox.equals = function (left, right) {
  return (
    left === right ||
    (defined(left) &&
      defined(right) &&
      Cartesian3.equals(left.center, right.center) &&
      Cartesian3.equals(left.minimum, right.minimum) &&
      Cartesian3.equals(left.maximum, right.maximum))
  );
};

var intersectScratch = new Cartesian3();
/**
 * Determines which side of a plane a box is located.
 *
 * @param {AxisAlignedBoundingBox} box The bounding box to test.
 * @param {Plane} plane The plane to test against.
 * @returns {Intersect} {@link Intersect.INSIDE} if the entire box is on the side of the plane
 *                      the normal is pointing, {@link Intersect.OUTSIDE} if the entire box is
 *                      on the opposite side, and {@link Intersect.INTERSECTING} if the box
 *                      intersects the plane.
 */
AxisAlignedBoundingBox.intersectPlane = function (box, plane) {
  //>>includeStart('debug', pragmas.debug);
  Check.defined("box", box);
  Check.defined("plane", plane);
  //>>includeEnd('debug');

  intersectScratch = Cartesian3.subtract(
    box.maximum,
    box.minimum,
    intersectScratch
  );
  var h = Cartesian3.multiplyByScalar(intersectScratch, 0.5, intersectScratch); //The positive half diagonal
  var normal = plane.normal;
  var e =
    h.x * Math.abs(normal.x) +
    h.y * Math.abs(normal.y) +
    h.z * Math.abs(normal.z);
  var s = Cartesian3.dot(box.center, normal) + plane.distance; //signed distance from center

  if (s - e > 0) {
    return Intersect.INSIDE;
  }

  if (s + e < 0) {
    //Not in front because normals point inward
    return Intersect.OUTSIDE;
  }

  return Intersect.INTERSECTING;
};

/**
 * Duplicates this AxisAlignedBoundingBox instance.
 *
 * @param {AxisAlignedBoundingBox} [result] The object onto which to store the result.
 * @returns {AxisAlignedBoundingBox} The modified result parameter or a new AxisAlignedBoundingBox instance if one was not provided.
 */
AxisAlignedBoundingBox.prototype.clone = function (result) {
  return AxisAlignedBoundingBox.clone(this, result);
};

/**
 * Determines which side of a plane this box is located.
 *
 * @param {Plane} plane The plane to test against.
 * @returns {Intersect} {@link Intersect.INSIDE} if the entire box is on the side of the plane
 *                      the normal is pointing, {@link Intersect.OUTSIDE} if the entire box is
 *                      on the opposite side, and {@link Intersect.INTERSECTING} if the box
 *                      intersects the plane.
 */
AxisAlignedBoundingBox.prototype.intersectPlane = function (plane) {
  return AxisAlignedBoundingBox.intersectPlane(this, plane);
};

/**
 * Compares this AxisAlignedBoundingBox against the provided AxisAlignedBoundingBox componentwise and returns
 * <code>true</code> if they are equal, <code>false</code> otherwise.
 *
 * @param {AxisAlignedBoundingBox} [right] The right hand side AxisAlignedBoundingBox.
 * @returns {Boolean} <code>true</code> if they are equal, <code>false</code> otherwise.
 */
AxisAlignedBoundingBox.prototype.equals = function (right) {
  return AxisAlignedBoundingBox.equals(this, right);
};
export default AxisAlignedBoundingBox;