Plane

Introduction

vtkPlane provides methods for various plane computations. These include
projecting points onto a plane, evaluating the plane equation, and returning
plane normal.

Methods

distanceToPlane

Return the distance of a point x to a plane defined by n (x-p0) = 0.
The normal n must be magnitude = 1.

Argument	Type	Required	Description
x	Vector3	Yes
origin	Vector3	Yes	The coordinate of the origin point.
normal	Vector3	Yes

distanceToPlane

Get the distance of a point x to a plane defined by n (x-p0) = 0.
The normal n must be magnitude = 1.

Argument	Type	Required	Description
x	Vector3	Yes	The point coordiante.

evaluate

Quick evaluation of plane equation n(x-origin) = 0.

Argument	Type	Required	Description
normal	Vector3	Yes
origin	Vector3	Yes	The coordinate of the origin point.
x	Vector3	Yes

evaluateFunction

Evaluate plane equation for point x.

Accepts both an array point representation and individual xyz arguments.

plane.evaluateFunction([0.0, 0.0, 0.0]);
plane.evaluateFunction(0.0, 0.0, 0.0);

Argument	Type	Required	Description
value	Vector3	Yes

evaluateFunction

Evaluate plane equation for point x.

Accepts both an array point representation and individual xyz arguments.

plane.evaluateFunction([0.0, 0.0, 0.0]);
plane.evaluateFunction(0.0, 0.0, 0.0);

Argument	Type	Required	Description
x	Number	Yes	The x coordinate.
y	Number	Yes	The y coordinate.
z	Number	Yes	The z coordinate.

evaluateGradient

Given the point xyz (three floating values) evaluate the equation for the
plane gradient. Note that the normal and origin must have already been
specified. The method returns an array of three floats.

Argument	Type	Required	Description
xyz		Yes

extend

Method used to decorate a given object (publicAPI+model) with vtkPlane characteristics.

Argument	Type	Required	Description
publicAPI		Yes	object on which methods will be bounds (public)
model		Yes	object on which data structure will be bounds (protected)
initialValues	IPlaneInitialValues	No	(default: {})

generalizedProjectPoint

Project a point x onto plane defined by origin and normal. The projected
point is returned in xproj.

!!! note
normal does NOT have to have magnitude 1.

Argument	Type	Required	Description
x	Vector3	Yes
origin	Vector3	Yes	The coordinate of the origin point.
normal	Vector3	Yes
xproj	Vector3	Yes

generalizedProjectPoint

Argument	Type	Required	Description
x	Vector3	Yes	The point coordinate.
xproj	Vector3	Yes	The projection point’s coordinate.

getNormal

Get plane normal.
Plane is defined by point and normal.

getNormalByReference

Get plane normal.
Plane is defined by point and normal.

getOrigin

Get the origin of the plane

getOriginByReference

Get the origin of the plane

intersectWithLine

Given a line defined by the two points p1,p2; and a plane defined by the normal n and point p0, compute an intersection.
Return an object:

let obj = {intersection: ..., betweenPoints: ..., t: ..., x: ...};

where:

• intersection (boolean): indicates if the plane and line intersect.
• betweenPoints (boolean): indicates if the intersection is between the provided points. True if (0 <= t <= 1), and false otherwise.
• t (Number): parametric coordinate along the line.
• x (Array): coordinates of intersection.

If the plane and line are parallel, intersection is false and t is set to
Number.MAX_VALUE.

Argument	Type	Required	Description
p1	Vector3	Yes
p2	Vector3	Yes
origin	Vector3	Yes	The coordinate of the origin point.
normal	Vector3	Yes

intersectWithLine

Given a line defined by the two points p1,p2; and a plane defined by the
normal n and point p0, compute an intersection. Return an object:

let obj = {intersection: ..., betweenPoints: ..., t: ..., x: ...};

where:

• intersection (boolean): indicates if the plane and line
  intersect.
• betweenPoints (boolean): indicates if the intersection is between
  the provided points. True if (0 <= t <= 1), and false otherwise.
• t (Number): parametric coordinate along the line.
• x (Array): coordinates of intersection.

If the plane and line are parallel, intersection is false and t is set to
Number.MAX_VALUE.

Argument	Type	Required	Description
p1	Vector3	Yes	The first point coordiante.
p2	Vector3	Yes	The second point coordiante.

intersectWithPlane

Given a planes defined by the normals n0 & n1 and origin points p0 & p1,
compute the line representing the plane intersection. Return an object:

let obj = {intersection: ..., error: ..., l0: ..., l1: ...};

where:

• intersection (boolean): indicates if the two planes intersect.
  Intersection is true if (0 <= t <= 1), and false otherwise.
• l0 (Array): coordinates of point 0 of the intersection line.
• l1 (Array): coordinates of point 1 of the intersection line.
• error (String|null): Conditional, if the planes do not intersect,
  is it because they are coplanar (COINCIDE) or parallel (DISJOINT).

Argument	Type	Required	Description
plane1Origin	Vector3	Yes
plane1Normal	Vector3	Yes
plane2Origin	Vector3	Yes
plane2Normal	Vector3	Yes

intersectWithPlane

Given a planes defined by the normals n0 & n1 and origin points p0 & p1,
compute the line representing the plane intersection. Return an object:

let obj = {intersection: ..., error: ..., l0: ..., l1: ...};

where:

• intersection (boolean): indicates if the two planes intersect.
  Intersection is true if (0 <= t <= 1), and false otherwise.
• l0 (Array): coordinates of point 0 of the intersection line.
• l1 (Array): coordinates of point 1 of the intersection line.
• error (String|null): Conditional, if the planes do not intersect,
  is it because they are coplanar (COINCIDE) or parallel (DISJOINT).

Argument	Type	Required	Description
planeOrigin	Vector3	Yes
planeNormal	Vector3	Yes

newInstance

Method used to create a new instance of vtkPlane.

Argument	Type	Required	Description
initialValues	IPlaneInitialValues	No	for pre-setting some of its content

projectPoint

Project a point x onto plane defined by origin and normal. The projected point
is returned in xproj.
!!! note
normal assumed to have magnitude 1.

Argument	Type	Required	Description
x	Vector3	Yes
origin	Vector3	Yes	The coordinate of the origin point.
normal	Vector3	Yes
xproj	Vector3	Yes

projectPoint

Argument	Type	Required	Description
x	Vector3	Yes	The point coordinate.
xproj	Vector3	Yes	The projection point’s coordinate.

projectVector

Project a vector v onto a plane defined by a normal. The projected vector is
returned in vproj.

Argument	Type	Required	Description
v	Vector3	Yes	The vector coordinate.
normal	Vector3	Yes
vproj	Vector3	Yes	The projection vector’s coordinate..

projectVector

Project a vector v onto plane. The projected vector is returned in vproj.

Argument	Type	Required	Description
v	Vector3	Yes	The vector coordinate.
vproj	Vector3	Yes	The projection vector’s coordinate..

push

Translate the plane in the direction of the normal by the distance
specified. Negative values move the plane in the opposite direction.

Argument	Type	Required	Description
distance	Number	Yes

setNormal

Set the normal of the plane.

Argument	Type	Required	Description
x	Number	Yes	The x coordinate.
y	Number	Yes	The y coordinate.
z	Number	Yes	The z coordinate.

setNormal

Set the normal of the plane.

Argument	Type	Required	Description
normal	Vector3	Yes	The normal coordinate.

setNormalFrom

Set the normal object.

Argument	Type	Required	Description
normal	Vector3	Yes	The normal coordinate.

setOrigin

Set the origin of the plane.

Argument	Type	Required	Description
x	Number	Yes	The x coordinate of the origin point.
y	Number	Yes	The y coordinate of the origin point.
z	Number	Yes	The z coordinate of the origin point.

setOrigin

Set the origin of the plane.

Argument	Type	Required	Description
origin	Vector3	Yes	The coordinate of the origin point.

setOriginFrom

Set the origin of the plane.

Argument	Type	Required	Description
origin	Vector3	Yes	The coordinate of the origin point.

Source

index.d.ts

import { vtkObject } from '../../../interfaces';
import { Vector3 } from '../../../types';
import vtkImplicitFunction from '../ImplicitFunction';

/**
 *
 */
export interface IPlaneInitialValues {
  normal?: Vector3;
  origin?: Vector3;
}

interface IIntersectWithLine {
  intersection: boolean;
  betweenPoints: boolean;
  t: number;
  x: Vector3;
}

export interface vtkPlane extends vtkImplicitFunction {
  /**
   * Get the distance of a point x to a plane defined by n (x-p0) = 0.
   * The normal n must be magnitude = 1.
   * @param {Vector3} x The point coordiante.
   */
  distanceToPlane(x: Vector3): number;

  /**
   * Get plane normal.
   * Plane is defined by point and normal.
   */
  getNormal(): Vector3;

  /**
   * Get plane normal.
   * Plane is defined by point and normal.
   */
  getNormalByReference(): Vector3;

  /**
   * Get the origin of the plane
   */
  getOrigin(): Vector3;

  /**
   * Get the origin of the plane
   */
  getOriginByReference(): Vector3;

  /**
   *
   * @param {Vector3} x The point coordinate.
   * @param {Vector3} xproj The projection point's coordinate.
   */
  projectPoint(x: Vector3, xproj: Vector3): void;

  /**
   * Project a vector v onto plane. The projected vector is returned in vproj.
   * @param {Vector3} v The vector coordinate.
   * @param {Vector3} vproj The projection vector's coordinate..
   */
  projectVector(v: Vector3, vproj: Vector3): void;

  /**
   * Translate the plane in the direction of the normal by the distance
   * specified. Negative values move the plane in the opposite direction.
   * @param {Number} distance
   */
  push(distance: number): void;

  /**
   *
   * @param {Vector3} x The point coordinate.
   * @param {Vector3} xproj The projection point's coordinate.
   */
  generalizedProjectPoint(x: Vector3, xproj: Vector3): void;

  /**
   * Evaluate plane equation for point x.
   *
   * Accepts both an array point representation and individual xyz arguments.
   *
   * ```js
   * plane.evaluateFunction([0.0, 0.0, 0.0]);
   * plane.evaluateFunction(0.0, 0.0, 0.0);
   * ```
   * @param {Number} x The x coordinate.
   * @param {Number} y The y coordinate.
   * @param {Number} z The z coordinate.
   */
  evaluateFunction(x: number, y: number, z: number): number;

  /**
   * Evaluate plane equation for point x.
   *
   * Accepts both an array point representation and individual xyz arguments.
   *
   * ```js
   * plane.evaluateFunction([0.0, 0.0, 0.0]);
   * plane.evaluateFunction(0.0, 0.0, 0.0);
   * ```
   * @param {Vector3} value
   */
  evaluateFunction(value: Vector3): number;

  /**
   * Given the point xyz (three floating values) evaluate the equation for the
   * plane gradient. Note that the normal and origin must have already been
   * specified. The method returns an array of three floats.
   * @param xyz
   */
  evaluateGradient(xyz: any): Vector3;

  /**
   * Given a line defined by the two points p1,p2; and a plane defined by the
   * normal n and point p0, compute an intersection. Return an object:
   *
   * ```js
   * let obj = {intersection: ..., betweenPoints: ..., t: ..., x: ...};
   * ```
   *
   * where:
   * - **intersection** (_boolean_): indicates if the plane and line
   *   intersect.
   * - **betweenPoints** (_boolean_): indicates if the intersection is between
   *   the provided points. True if (0 <= t <= 1), and false otherwise.
   * - **t** (_Number_): parametric coordinate along the line.
   * - **x** (_Array_): coordinates of intersection.
   *
   * If the plane and line are parallel, intersection is false and t is set to
   * Number.MAX_VALUE.
   * @param {Vector3} p1 The first point coordiante.
   * @param {Vector3} p2 The second point coordiante.
   */
  intersectWithLine(p1: Vector3, p2: Vector3): IIntersectWithLine;

  /**
   * Given a planes defined by the normals n0 & n1 and origin points p0 & p1,
   * compute the line representing the plane intersection. Return an object:
   *
   * ```js
   * let obj = {intersection: ..., error: ..., l0: ..., l1: ...};
   * ```
   *
   * where:
   *
   * - **intersection** (_boolean_): indicates if the two planes intersect.
   *   Intersection is true if (0 <= t <= 1), and false otherwise.
   * - **l0** (_Array_): coordinates of point 0 of the intersection line.
   * - **l1** (_Array_): coordinates of point 1 of the intersection line.
   * - **error** (_String|null_): Conditional, if the planes do not intersect,
   *   is it because they are coplanar (`COINCIDE`) or parallel (`DISJOINT`).
   * @param {Vector3} planeOrigin
   * @param {Vector3} planeNormal
   */
  intersectWithPlane(
    planeOrigin: Vector3,
    planeNormal: Vector3
  ): IIntersectWithLine;

  /**
   * Set the normal of the plane.
   * @param {Vector3} normal The normal coordinate.
   */
  setNormal(normal: Vector3): boolean;

  /**
   * Set the normal of the plane.
   * @param {Number} x The x coordinate.
   * @param {Number} y The y coordinate.
   * @param {Number} z The z coordinate.
   */
  setNormal(x: number, y: number, z: number): boolean;

  /**
   * Set the normal object.
   * @param {Vector3} normal The normal coordinate.
   */
  setNormalFrom(normal: Vector3): boolean;

  /**
   * Set the origin of the plane.
   * @param {Vector3} origin The coordinate of the origin point.
   */
  setOrigin(origin: Vector3): boolean;

  /**
   * Set the origin of the plane.
   * @param {Number} x The x coordinate of the origin point.
   * @param {Number} y The y coordinate of the origin point.
   * @param {Number} z The z coordinate of the origin point.
   */
  setOrigin(x: number, y: number, z: number): boolean;

  /**
   * Set the origin of the plane.
   * @param {Vector3} origin The coordinate of the origin point.
   */
  setOriginFrom(origin: Vector3): boolean;
}

/**
 * Method used to decorate a given object (publicAPI+model) with vtkPlane characteristics.
 *
 * @param publicAPI object on which methods will be bounds (public)
 * @param model object on which data structure will be bounds (protected)
 * @param {IPlaneInitialValues} [initialValues] (default: {})
 */
export function extend(
  publicAPI: object,
  model: object,
  initialValues?: IPlaneInitialValues
): void;

/**
 * Method used to create a new instance of vtkPlane.
 * @param {IPlaneInitialValues} [initialValues] for pre-setting some of its content
 */
export function newInstance(initialValues?: IPlaneInitialValues): vtkPlane;

/**
 * Quick evaluation of plane equation n(x-origin) = 0.
 * @static
 * @param {Vector3} normal
 * @param {Vector3} origin The coordinate of the origin point.
 * @param {Vector3} x
 */
export function evaluate(normal: Vector3, origin: Vector3, x: Vector3): number;

/**
 * Return the distance of a point x to a plane defined by n (x-p0) = 0.
 * The normal n must be magnitude = 1.
 * @static
 * @param {Vector3} x
 * @param {Vector3} origin The coordinate of the origin point.
 * @param {Vector3} normal
 */
export function distanceToPlane(
  x: Vector3,
  origin: Vector3,
  normal: Vector3
): number;

/**
 * Project a point x onto plane defined by origin and normal. The projected point
 * is returned in xproj.
 * !!! note
 *     normal assumed to have magnitude 1.
 * @static
 * @param {Vector3} x
 * @param {Vector3} origin The coordinate of the origin point.
 * @param {Vector3} normal
 * @param {Vector3} xproj
 */
export function projectPoint(
  x: any,
  origin: Vector3,
  normal: Vector3,
  xproj: Vector3
): void;

/**
 * Project a vector v onto a plane defined by a normal. The projected vector is
 * returned in vproj.
 * @static
 * @param {Vector3} v The vector coordinate.
 * @param {Vector3} normal
 * @param {Vector3} vproj The projection vector's coordinate..
 */
export function projectVector(
  v: Vector3,
  normal: Vector3,
  vproj: Vector3
): void;

/**
 * Project a point x onto plane defined by origin and normal. The projected
   point is returned in xproj. 
 * 
 * !!! note
 *     normal does NOT have to have magnitude 1.
 * @static
 * @param {Vector3} x 
 * @param {Vector3} origin The coordinate of the origin point.
 * @param {Vector3} normal 
 * @param {Vector3} xproj 
 */
export function generalizedProjectPoint(
  x: any,
  origin: Vector3,
  normal: Vector3,
  xproj: Vector3
): void;

/**
 * Given a line defined by the two points p1,p2; and a plane defined by the normal n and point p0, compute an intersection.
 * Return an object:
 *
 * ```js
 * let obj = {intersection: ..., betweenPoints: ..., t: ..., x: ...};
 * ```
 *
 * where:
 * - **intersection** (_boolean_): indicates if the plane and line intersect.
 * - **betweenPoints** (_boolean_): indicates if the intersection is between the provided points. True if (0 <= t <= 1), and false otherwise.
 * - **t** (_Number_): parametric coordinate along the line.
 * - **x** (_Array_): coordinates of intersection.
 *
 * If the plane and line are parallel, intersection is false and t is set to
 * Number.MAX_VALUE.
 * @static
 * @param {Vector3} p1
 * @param {Vector3} p2
 * @param {Vector3} origin The coordinate of the origin point.
 * @param {Vector3} normal
 */
export function intersectWithLine(
  p1: Vector3,
  p2: Vector3,
  origin: Vector3,
  normal: Vector3
): IIntersectWithLine;

/**
 *  Given a planes defined by the normals n0 & n1 and origin points p0 & p1,
 *  compute the line representing the plane intersection. Return an object:
 *
 *  ```js
 *  let obj = {intersection: ..., error: ..., l0: ..., l1: ...};
 *  ```
 *
 *  where:
 *
 *  - **intersection** (_boolean_): indicates if the two planes intersect.
 *    Intersection is true if (0 <= t <= 1), and false otherwise.
 *  - **l0** (_Array_): coordinates of point 0 of the intersection line.
 *  - **l1** (_Array_): coordinates of point 1 of the intersection line.
 *  - **error** (_String|null_): Conditional, if the planes do not intersect,
 *    is it because they are coplanar (`COINCIDE`) or parallel (`DISJOINT`).
 * @static
 * @param {Vector3} plane1Origin
 * @param {Vector3} plane1Normal
 * @param {Vector3} plane2Origin
 * @param {Vector3} plane2Normal
 */
export function intersectWithPlane(
  plane1Origin: Vector3,
  plane1Normal: Vector3,
  plane2Origin: Vector3,
  plane2Normal: Vector3
): IIntersectWithLine;

/**
 * Constants for the `intersectWithPlane` function.
 */
export declare const COINCIDE: string;

/**
 * Constants for the `intersectWithPlane` function.
 */
export declare const DISJOINT: string;

/**
 * vtkPlane provides methods for various plane computations. These include
 * projecting points onto a plane, evaluating the plane equation, and returning
 * plane normal.
 */
export declare const vtkPlane: {
  newInstance: typeof newInstance;
  extend: typeof extend;
  evaluate: typeof evaluate;
  distanceToPlane: typeof distanceToPlane;
  projectPoint: typeof projectPoint;
  projectVector: typeof projectVector;
  generalizedProjectPoint: typeof generalizedProjectPoint;
  intersectWithLine: typeof intersectWithLine;
  intersectWithPlane: typeof intersectWithPlane;
};
export default vtkPlane;

index.js

import * as vtkMath from 'vtk.js/Sources/Common/Core/Math';
import macro from 'vtk.js/Sources/macros';
import vtkImplicitFunction from 'vtk.js/Sources/Common/DataModel/ImplicitFunction';

const PLANE_TOLERANCE = 1.0e-6;
const COINCIDE = 'coincide';
const DISJOINT = 'disjoint';

// ----------------------------------------------------------------------------
// Global methods
// ----------------------------------------------------------------------------

function evaluate(normal, origin, x) {
  return (
    normal[0] * (x[0] - origin[0]) +
    normal[1] * (x[1] - origin[1]) +
    normal[2] * (x[2] - origin[2])
  );
}

function distanceToPlane(x, origin, normal) {
  const distance =
    normal[0] * (x[0] - origin[0]) +
    normal[1] * (x[1] - origin[1]) +
    normal[2] * (x[2] - origin[2]);

  return Math.abs(distance);
}

function projectPoint(x, origin, normal, xproj) {
  const xo = [];
  vtkMath.subtract(x, origin, xo);

  const t = vtkMath.dot(normal, xo);

  xproj[0] = x[0] - t * normal[0];
  xproj[1] = x[1] - t * normal[1];
  xproj[2] = x[2] - t * normal[2];
}

function projectVector(v, normal, vproj) {
  const t = vtkMath.dot(v, normal);

  let n2 = vtkMath.dot(normal, normal);
  if (n2 === 0) {
    n2 = 1.0;
  }

  vproj[0] = v[0] - (t * normal[0]) / n2;
  vproj[1] = v[1] - (t * normal[1]) / n2;
  vproj[2] = v[2] - (t * normal[2]) / n2;
  return vproj;
}

function generalizedProjectPoint(x, origin, normal, xproj) {
  const xo = [];
  vtkMath.subtract(x, origin, xo);

  const t = vtkMath.dot(normal, xo);
  const n2 = vtkMath.dot(normal, normal);

  if (n2 !== 0) {
    xproj[0] = x[0] - (t * normal[0]) / n2;
    xproj[1] = x[1] - (t * normal[1]) / n2;
    xproj[2] = x[2] - (t * normal[2]) / n2;
  } else {
    xproj[0] = x[0];
    xproj[1] = x[1];
    xproj[2] = x[2];
  }
}

function intersectWithLine(p1, p2, origin, normal) {
  const outObj = {
    intersection: false,
    betweenPoints: false,
    t: Number.MAX_VALUE,
    x: [],
  };

  const p21 = [];
  const p1Origin = [];
  // Compute line vector
  vtkMath.subtract(p2, p1, p21);
  vtkMath.subtract(origin, p1, p1Origin);

  // Compute denominator.  If ~0, line and plane are parallel.
  // const num = vtkMath.dot(normal, origin) - vtkMath.dot(normal, p1);
  const num = vtkMath.dot(normal, p1Origin);
  const den = vtkMath.dot(normal, p21);

  // If denominator with respect to numerator is "zero", then the line and
  // plane are considered parallel.
  let fabsden;
  let fabstolerance;

  // Trying to avoid an expensive call to fabs()
  if (den < 0.0) {
    fabsden = -den;
  } else {
    fabsden = den;
  }
  if (num < 0.0) {
    fabstolerance = -num * PLANE_TOLERANCE;
  } else {
    fabstolerance = num * PLANE_TOLERANCE;
  }
  if (fabsden <= fabstolerance) {
    return outObj;
  }

  // Where on the line between p1 and p2 is the intersection
  // If between 0 and 1, it is between the two points. If < 0 it's before p1, if > 1 it's after p2
  outObj.t = num / den;

  outObj.x[0] = p1[0] + outObj.t * p21[0];
  outObj.x[1] = p1[1] + outObj.t * p21[1];
  outObj.x[2] = p1[2] + outObj.t * p21[2];

  outObj.intersection = true;
  outObj.betweenPoints = outObj.t >= 0.0 && outObj.t <= 1.0;
  return outObj;
}

function intersectWithPlane(
  plane1Origin,
  plane1Normal,
  plane2Origin,
  plane2Normal
) {
  const outObj = {
    intersection: false,
    l0: [],
    l1: [],
    error: null,
  };

  const cross = [];
  vtkMath.cross(plane1Normal, plane2Normal, cross);
  const absCross = cross.map((n) => Math.abs(n));

  // test if the two planes are parallel
  if (absCross[0] + absCross[1] + absCross[2] < PLANE_TOLERANCE) {
    // test if disjoint or coincide
    const v = [];
    vtkMath.subtract(plane1Origin, plane2Origin, v);
    if (vtkMath.dot(plane1Normal, v) === 0) {
      outObj.error = COINCIDE;
    } else {
      outObj.error = DISJOINT;
    }
    return outObj;
  }

  // Plane1 and Plane2 intersect in a line
  // first determine max abs coordinate of the cross product
  let maxc;
  if (absCross[0] > absCross[1] && absCross[0] > absCross[2]) {
    maxc = 'x';
  } else if (absCross[1] > absCross[2]) {
    maxc = 'y';
  } else {
    maxc = 'z';
  }

  // To get a point on the intersect line, zero the max coord, and solve for the other two
  const iP = []; // intersectionPoint
  // the constants in the 2 plane equations
  const d1 = -vtkMath.dot(plane1Normal, plane1Origin);
  const d2 = -vtkMath.dot(plane2Normal, plane2Origin);

  // eslint-disable-next-line default-case
  switch (maxc) {
    case 'x': // intersect with x=0
      iP[0] = 0;
      iP[1] = (d2 * plane1Normal[2] - d1 * plane2Normal[2]) / cross[0];
      iP[2] = (d1 * plane2Normal[1] - d2 * plane1Normal[1]) / cross[0];
      break;
    case 'y': // intersect with y=0
      iP[0] = (d1 * plane2Normal[2] - d2 * plane1Normal[2]) / cross[1];
      iP[1] = 0;
      iP[2] = (d2 * plane1Normal[0] - d1 * plane2Normal[0]) / cross[1];
      break;
    case 'z': // intersect with z=0
      iP[0] = (d2 * plane1Normal[1] - d1 * plane2Normal[1]) / cross[2];
      iP[1] = (d1 * plane2Normal[0] - d2 * plane1Normal[0]) / cross[2];
      iP[2] = 0;
      break;
  }

  outObj.l0 = iP;
  vtkMath.add(iP, cross, outObj.l1);
  outObj.intersection = true;

  return outObj;
}

// ----------------------------------------------------------------------------
// Static API
// ----------------------------------------------------------------------------

export const STATIC = {
  evaluate,
  distanceToPlane,
  projectPoint,
  projectVector,
  generalizedProjectPoint,
  intersectWithLine,
  intersectWithPlane,
  DISJOINT,
  COINCIDE,
};

// ----------------------------------------------------------------------------
// vtkPlane methods
// ----------------------------------------------------------------------------

export function vtkPlane(publicAPI, model) {
  // Set our className
  model.classHierarchy.push('vtkPlane');

  publicAPI.distanceToPlane = (x) =>
    distanceToPlane(x, model.origin, model.normal);

  publicAPI.projectPoint = (x, xproj) => {
    projectPoint(x, model.origin, model.normal, xproj);
  };

  publicAPI.projectVector = (v, vproj) => projectVector(v, model.normal, vproj);

  publicAPI.push = (distance) => {
    if (distance === 0.0) {
      return;
    }
    for (let i = 0; i < 3; i++) {
      model.origin[i] += distance * model.normal[i];
    }
  };

  publicAPI.generalizedProjectPoint = (x, xproj) => {
    generalizedProjectPoint(x, model.origin, model.normal, xproj);
  };

  publicAPI.evaluateFunction = (x, y, z) => {
    if (!Array.isArray(x)) {
      return (
        model.normal[0] * (x - model.origin[0]) +
        model.normal[1] * (y - model.origin[1]) +
        model.normal[2] * (z - model.origin[2])
      );
    }
    return (
      model.normal[0] * (x[0] - model.origin[0]) +
      model.normal[1] * (x[1] - model.origin[1]) +
      model.normal[2] * (x[2] - model.origin[2])
    );
  };

  publicAPI.evaluateGradient = (xyz) => {
    const retVal = [model.normal[0], model.normal[1], model.normal[2]];
    return retVal;
  };

  publicAPI.intersectWithLine = (p1, p2) =>
    intersectWithLine(p1, p2, model.origin, model.normal);

  publicAPI.intersectWithPlane = (planeOrigin, planeNormal) =>
    intersectWithPlane(planeOrigin, planeNormal, model.origin, model.normal);
}

// ----------------------------------------------------------------------------
// Object factory
// ----------------------------------------------------------------------------

const DEFAULT_VALUES = {
  normal: [0.0, 0.0, 1.0],
  origin: [0.0, 0.0, 0.0],
};

// ----------------------------------------------------------------------------

export function extend(publicAPI, model, initialValues = {}) {
  Object.assign(model, DEFAULT_VALUES, initialValues);

  // Object methods
  vtkImplicitFunction.extend(publicAPI, model, initialValues);

  macro.setGetArray(publicAPI, model, ['normal', 'origin'], 3);

  vtkPlane(publicAPI, model);
}

// ----------------------------------------------------------------------------

export const newInstance = macro.newInstance(extend, 'vtkPlane');

// ----------------------------------------------------------------------------

export default { newInstance, extend, ...STATIC };