transformation-matrix/src/applyToPoint.js

2d transformation matrix functions written in ES6 syntax. Tree shaking ready!

/**
 * Calculate a point transformed with an affine matrix
 * @param matrix {Matrix} Affine Matrix
 * @param  point {Point} Point
 * @returns {Point} Point
 */
export function applyToPoint (matrix, point) {
  return Array.isArray(point)
    ? [
        matrix.a * point[0] + matrix.c * point[1] + matrix.e,
        matrix.b * point[0] + matrix.d * point[1] + matrix.f
      ]
    : {
        x: matrix.a * point.x + matrix.c * point.y + matrix.e,
        y: matrix.b * point.x + matrix.d * point.y + matrix.f
      }
}

/**
 * Calculate an array of points transformed with an affine matrix
 * @param matrix {Matrix} Affine Matrix
 * @param points {Point[]} Array of point
 * @returns {Point[]} Array of point
 */
export function applyToPoints (matrix, points) {
  return points.map(point => applyToPoint(matrix, point))
}