Source: gfx/core/math/Matrix.js

// @todo - ignore the too many parameters warning for now
// should either fix it or change the jshint config
// jshint -W072

const Vector = require('engine/Vector');

/**
 * The pixi Matrix class as an object, which makes it a lot faster,
 * here is a representation of it :
 * | a | b | tx|
 * | c | d | ty|
 * | 0 | 0 | 1 |
 *
 * @class
 */
class Matrix {
  /**
   * @constructor
   */
  constructor() {
    /**
     * @member {number}
     * @default 1
     */
    this.a = 1;

    /**
     * @member {number}
     * @default 0
     */
    this.b = 0;

    /**
     * @member {number}
     * @default 0
     */
    this.c = 0;

    /**
     * @member {number}
     * @default 1
     */
    this.d = 1;

    /**
     * @member {number}
     * @default 0
     */
    this.tx = 0;

    /**
     * @member {number}
     * @default 0
     */
    this.ty = 0;
  }

  /**
   * Creates a Matrix object based on the given array. The Element to Matrix mapping order is as follows:
   *
   * a = array[0]
   * b = array[1]
   * c = array[3]
   * d = array[4]
   * tx = array[2]
   * ty = array[5]
   *
   * @param {number[]} array The array that the matrix will be populated from.
   */
  fromArray(array) {
    this.a = array[0];
    this.b = array[1];
    this.c = array[3];
    this.d = array[4];
    this.tx = array[2];
    this.ty = array[5];
  }


  /**
   * sets the matrix properties
   *
   * @param {number} a  Matrix property a
   * @param {number} b  Matrix property b
   * @param {number} c  Matrix property c
   * @param {number} d  Matrix property d
   * @param {number} tx Matrix property tx
   * @param {number} ty Matrix property ty
   *
   * @return {Matrix} This matrix. Good for chaining method calls.
   */
  set(a, b, c, d, tx, ty) {
    this.a = a;
    this.b = b;
    this.c = c;
    this.d = d;
    this.tx = tx;
    this.ty = ty;

    return this;
  }


  /**
   * Creates an array from the current Matrix object.
   *
   * @param {boolean} transpose Whether we need to transpose the matrix or not
   * @param {Array} [out]       If provided the array will be assigned to out
   * @return {number[]}         the newly created array which contains the matrix
   */
  toArray(transpose, out) {
    if (!this.array) {
      this.array = new Float32Array(9);
    }

    var array = out || this.array;

    if (transpose) {
      array[0] = this.a;
      array[1] = this.b;
      array[2] = 0;
      array[3] = this.c;
      array[4] = this.d;
      array[5] = 0;
      array[6] = this.tx;
      array[7] = this.ty;
      array[8] = 1;
    }
    else {
      array[0] = this.a;
      array[1] = this.c;
      array[2] = this.tx;
      array[3] = this.b;
      array[4] = this.d;
      array[5] = this.ty;
      array[6] = 0;
      array[7] = 0;
      array[8] = 1;
    }

    return array;
  }

  /**
   * Get a new position with the current transformation applied.
   * Can be used to go from a child's coordinate space to the world coordinate space. (e.g. rendering)
   *
   * @param {Vector} pos      The origin
   * @param {Vector} [newPos] The point that the new position is assigned to (allowed to be same as input)
   * @return {Vector}         The new point, transformed through this matrix
   */
  apply(pos, newPos) {
    newPos = newPos || new Vector();

    var x = pos.x;
    var y = pos.y;

    newPos.x = this.a * x + this.c * y + this.tx;
    newPos.y = this.b * x + this.d * y + this.ty;

    return newPos;
  }

  /**
   * Get a new position with the inverse of the current transformation applied.
   * Can be used to go from the world coordinate space to a child's coordinate space. (e.g. input)
   *
   * @param {Vector} pos      The origin
   * @param {Vector} [newPos] The point that the new position is assigned to (allowed to be same as input)
   * @return {Vector}         The new point, inverse-transformed through this matrix
   */
  applyInverse(pos, newPos) {
    newPos = newPos || new Vector();

    var id = 1 / (this.a * this.d + this.c * -this.b);

    var x = pos.x;
    var y = pos.y;

    newPos.x = this.d * id * x + -this.c * id * y + (this.ty * this.c - this.tx * this.d) * id;
    newPos.y = this.a * id * y + -this.b * id * x + (-this.ty * this.a + this.tx * this.b) * id;

    return newPos;
  }

  /**
   * Translates the matrix on the x and y.
   *
   * @param {number} x  The amount to move on x axis
   * @param {number} y  The amount to move on y axis
   * @return {Matrix}   This matrix. Good for chaining method calls.
   */
  translate(x, y) {
    this.tx += x;
    this.ty += y;

    return this;
  }

  /**
   * Applies a scale transformation to the matrix.
   *
   * @param {number} x  The amount to scale horizontally
   * @param {number} y  The amount to scale vertically
   * @return {Matrix}   This matrix. Good for chaining method calls.
   */
  scale(x, y) {
    this.a *= x;
    this.d *= y;
    this.c *= x;
    this.b *= y;
    this.tx *= x;
    this.ty *= y;

    return this;
  }


  /**
   * Applies a rotation transformation to the matrix.
   *
   * @param {number} angle  The angle in radians.
   * @return {Matrix}       This matrix. Good for chaining method calls.
   */
  rotate(angle) {
    var cos = Math.cos(angle);
    var sin = Math.sin(angle);

    var a1 = this.a;
    var c1 = this.c;
    var tx1 = this.tx;

    this.a = a1 * cos - this.b * sin;
    this.b = a1 * sin + this.b * cos;
    this.c = c1 * cos - this.d * sin;
    this.d = c1 * sin + this.d * cos;
    this.tx = tx1 * cos - this.ty * sin;
    this.ty = tx1 * sin + this.ty * cos;

    return this;
  }

  /**
   * Appends the given Matrix to this Matrix.
   *
   * @param {Matrix} matrix   Matrix to append
   * @return {Matrix}         This matrix. Good for chaining method calls.
   */
  append(matrix) {
    var a1 = this.a;
    var b1 = this.b;
    var c1 = this.c;
    var d1 = this.d;

    this.a = matrix.a * a1 + matrix.b * c1;
    this.b = matrix.a * b1 + matrix.b * d1;
    this.c = matrix.c * a1 + matrix.d * c1;
    this.d = matrix.c * b1 + matrix.d * d1;

    this.tx = matrix.tx * a1 + matrix.ty * c1 + this.tx;
    this.ty = matrix.tx * b1 + matrix.ty * d1 + this.ty;

    return this;
  }

  /**
   * Sets the matrix based on all the available properties
   *
   * @param {number} x          Position x
   * @param {number} y          Position y
   * @param {number} pivotX     Pivot x
   * @param {number} pivotY     Pivot y
   * @param {number} scaleX     Scale x
   * @param {number} scaleY     Scale y
   * @param {number} rotation   Rotation
   * @param {number} skewX      Skew x
   * @param {number} skewY      Skew y
   *
   * @return {Matrix}           This matrix. Good for chaining method calls.
   */
  setTransform(x, y, pivotX, pivotY, scaleX, scaleY, rotation, skewX, skewY) {
    var a, b, c, d, sr, cr, cy, sy, nsx, cx;

    sr = Math.sin(rotation);
    cr = Math.cos(rotation);
    cy = Math.cos(skewY);
    sy = Math.sin(skewY);
    nsx = -Math.sin(skewX);
    cx = Math.cos(skewX);

    a = cr * scaleX;
    b = sr * scaleX;
    c = -sr * scaleY;
    d = cr * scaleY;

    this.a = cy * a + sy * c;
    this.b = cy * b + sy * d;
    this.c = nsx * a + cx * c;
    this.d = nsx * b + cx * d;

    this.tx = x + (pivotX * a + pivotY * c);
    this.ty = y + (pivotX * b + pivotY * d);

    return this;
  }

  /**
   * Prepends the given Matrix to this Matrix.
   *
   * @param {Matrix} matrix   Matrix to prepend
   * @return {Matrix}         This matrix. Good for chaining method calls.
   */
  prepend(matrix) {
    var tx1 = this.tx;

    if (matrix.a !== 1 || matrix.b !== 0 || matrix.c !== 0 || matrix.d !== 1) {
      var a1 = this.a;
      var c1 = this.c;
      this.a = a1 * matrix.a + this.b * matrix.c;
      this.b = a1 * matrix.b + this.b * matrix.d;
      this.c = c1 * matrix.a + this.d * matrix.c;
      this.d = c1 * matrix.b + this.d * matrix.d;
    }

    this.tx = tx1 * matrix.a + this.ty * matrix.c + matrix.tx;
    this.ty = tx1 * matrix.b + this.ty * matrix.d + matrix.ty;

    return this;
  }

  /**
   * Inverts this matrix
   *
   * @return {Matrix} This matrix. Good for chaining method calls.
   */
  invert() {
    var a1 = this.a;
    var b1 = this.b;
    var c1 = this.c;
    var d1 = this.d;
    var tx1 = this.tx;
    var n = a1 * d1 - b1 * c1;

    this.a = d1 / n;
    this.b = -b1 / n;
    this.c = -c1 / n;
    this.d = a1 / n;
    this.tx = (c1 * this.ty - d1 * tx1) / n;
    this.ty = -(a1 * this.ty - b1 * tx1) / n;

    return this;
  }


  /**
   * Resets this Matix to an identity (default) matrix.
   *
   * @return {Matrix} This matrix. Good for chaining method calls.
   */
  identity() {
    this.a = 1;
    this.b = 0;
    this.c = 0;
    this.d = 1;
    this.tx = 0;
    this.ty = 0;

    return this;
  }

  /**
   * Creates a new Matrix object with the same values as this one.
   *
   * @return {Matrix} A copy of this matrix. Good for chaining method calls.
   */
  clone() {
    let matrix = new Matrix();
    matrix.a = this.a;
    matrix.b = this.b;
    matrix.c = this.c;
    matrix.d = this.d;
    matrix.tx = this.tx;
    matrix.ty = this.ty;

    return matrix;
  }

  /**
   * Changes the values of the given matrix to be the same as the ones in this matrix
   *
   * @param {Matrix} matrix   Target matrix to set to
   * @return {Matrix}         The matrix given in parameter with its values updated.
   */
  copy(matrix) {
    matrix.a = this.a;
    matrix.b = this.b;
    matrix.c = this.c;
    matrix.d = this.d;
    matrix.tx = this.tx;
    matrix.ty = this.ty;

    return matrix;
  }
}

/**
 * A default (identity) matrix
 *
 * @static
 * @const
 */
Matrix.IDENTITY = new Matrix();

/**
 * A temp matrix
 *
 * @static
 * @const
 */
Matrix.TEMP_MATRIX = new Matrix();

module.exports = Matrix;