svgdom/src/other/Box.js

Straightforward DOM implementation for SVG, HTML and XML

import * as regex from '../utils/regex.js'
import { Point } from './Point.js'

export class Box {
  constructor (source) {
    var base = [ 0, 0, 0, 0 ]
    source = typeof source === 'string' ? source.split(regex.delimiter).map(parseFloat)
      : Array.isArray(source) ? source
      : typeof source === 'object' ? [
        source.left != null ? source.left : source.x,
        source.top != null ? source.top : source.y,
        source.width,
        source.height
      ]
      : arguments.length === 4 ? [].slice.call(arguments)
      : base

    this.x = this.left = source[0]
    this.y = this.top = source[1]
    this.width = source[2]
    this.height = source[3]
    this.right = this.left + this.width
    this.bottom = this.top + this.height
  }

  // Merge rect box with another, return a new instance
  merge (box) {
    if (box instanceof NoBox) return new Box(this)

    var x = Math.min(this.x, box.x)
    var y = Math.min(this.y, box.y)

    return new Box(
      x, y,
      Math.max(this.x + this.width, box.x + box.width) - x,
      Math.max(this.y + this.height, box.y + box.height) - y
    )
  }

  transform (m) {
    var xMin = Infinity
    var xMax = -Infinity
    var yMin = Infinity
    var yMax = -Infinity

    var pts = [
      new Point(this.x, this.y),
      new Point(this.x + this.width, this.y),
      new Point(this.x, this.y + this.height),
      new Point(this.x + this.width, this.y + this.height)
    ]

    pts.forEach(function (p) {
      p = p.transform(m)
      xMin = Math.min(xMin, p.x)
      xMax = Math.max(xMax, p.x)
      yMin = Math.min(yMin, p.y)
      yMax = Math.max(yMax, p.y)
    })

    return new Box(
      xMin, yMin,
      xMax - xMin,
      yMax - yMin
    )
  }
}

export class NoBox extends Box {
  // NoBox has no valid values so it cant be merged
  merge (box) {
    return box instanceof NoBox ? new NoBox() : new Box(box)
  }

  transform (m) {
    return new NoBox()
  }
}