tsmathlib/src/math/matrix3x3.ts

Typescript Version Math/Physics/CG Library

/*
 * @Author: Xu.Wang
 * @Date: 2020-04-05 20:24:10
 * @Last Modified by: Xu.Wang
 * @Last Modified time: 2020-04-06 02:12:07
 */
import { Matrix } from './matrix'
import { Vector3 } from './vector3'
import { TS_MAX_NUM } from './math_constants'

export class Matrix3x3 extends Matrix {
  constructor(params?: Array<number>) {
    if (params === undefined) {
      // set to identity matrix
      params = new Array<number>(1, 0, 0, 0, 1, 0, 0, 0, 1)
    } else {
      // check size
      if (9 !== params.length) {
        console.log(
          'Matrix3x3 init error: size is not equal to 9, size is:',
          params.length
        )
        return
      }
    }

    super(3, 3, params)
  }

  private _identity(): Array<number> {
    return new Array<number>(1, 0, 0, 0, 1, 0, 0, 0, 1)
  }

  identity() {
    return new Matrix3x3(this._identity())
  }

  mulV3(v3: Vector3): Vector3 {
    // check shape
    if (v3.size() !== this.cols()) {
      console.log('vector shape is not right!', v3.size(), this.cols())
      return new Vector3(-TS_MAX_NUM, -TS_MAX_NUM, -TS_MAX_NUM)
    }

    let vec2mat = new Matrix(v3.size(), 1, v3.data())
    let mat = this.mulMat(vec2mat)

    let vec = mat.mat2Vec()

    return new Vector3(vec.data()[0], vec.data()[1], vec.data()[2])
  }

  // OpenGL Helper
  scaleMatrix(sx: number, sy: number, sz: number) {
    return new Matrix3x3(new Array<number>(sx, 0, 0, 0, sy, 0, 0, 0, sz))
  }

  rotationMatrix(axis: Vector3, rad: number) {
    return new Matrix3x3(
      new Array<number>(
        1 + (1 - Math.cos(rad)) * (axis.x() * axis.x() - 1),
        -axis.z() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.x() * axis.y(),
        axis.y() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.x() * axis.z(),

        axis.z() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.x() * axis.y(),
        1 + (1 - Math.cos(rad)) * (axis.y() * axis.y() - 1),
        -axis.x() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.y() * axis.z(),

        -axis.y() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.x() * axis.z(),
        axis.x() * Math.sin(rad) + (1 - Math.cos(rad)) * axis.y() * axis.z(),
        1 + (1 - Math.cos(rad)) * (axis.z() * axis.z() - 1)
      )
    )
  }
}