@monogrid/js-utils v1.1.0

@monogrid/js-utils

This is a collection of generic Javascript utilities to help develpment on MONOGRID sites.

Installation

npm install --save @monogrid/js-utils

or

yarn add @monogrid/js-utils

Modules

Classes

FileUtils

A collection of File related utilities.

• FileUtils
  • ~downloadFile(content, fileName, contentType)
  • ~loadFile([accept]) ⇒ Promise.<Array>
  • ~loadJSON() ⇒ Promise.<String>
  • ~loadImage() ⇒ Promise.<Image>

FileUtils~downloadFile(content, fileName, contentType)

Downloads a file to the user's machine.

Kind: inner method of FileUtils

FileUtils~loadFile(accept) ⇒ Promise.<Array>

Prompts the user to select a single file from his harddrive.

Kind: inner method of FileUtils
Returns: Promise.<Array> - Array of files selected by the user.

FileUtils~loadJSON() ⇒ Promise.<String>

Prompts the user to select a single JSON file from his harddrive and returns the result of his selection.

Kind: inner method of FileUtils
Returns: Promise.<String> - The parsed JSON file.

FileUtils~loadImage() ⇒ Promise.<Image>

Prompts the user to select a single JSON file from his harddrive and returns the result of his selection

Kind: inner method of FileUtils
Returns: Promise.<Image> - The selected image object.

normalizeWheel

An utility function to normalize the mouseWheel input in the browser.

Typechecks:

normalizeWheel~normalizeWheel()

Mouse wheel (and 2-finger trackpad) support on the web sucks. It is complicated, thus this doc is long and (hopefully) detailed enough to answer your questions.

If you need to react to the mouse wheel in a predictable way, this code is like your bestest friend. hugs

As of today, there are 4 DOM event types you can listen to:

'wheel' -- Chrome(31+), FF(17+), IE(9+) 'mousewheel' -- Chrome, IE(6+), Opera, Safari 'MozMousePixelScroll' -- FF(3.5 only!) (2010-2013) -- don't bother! 'DOMMouseScroll' -- FF(0.9.7+) since 2003

So what to do? The is the best:

normalizeWheel.getEventType()

In your event callback, use this code to get sane interpretation of the deltas. This code will return an object with properties:

spinX -- normalized spin speed (use for zoom) - x plane spinY -- " - y plane pixelX -- normalized distance (to pixels) - x plane pixelY -- " - y plane

Wheel values are provided by the browser assuming you are using the wheel to scroll a web page by a number of lines or pixels (or pages). Values can lety significantly on different platforms and browsers, forgetting that you can scroll at different speeds. Some devices (like trackpads) emit more events at smaller increments with fine granularity, and some emit massive jumps with linear speed or acceleration.

This code does its best to normalize the deltas for you:

• spin is trying to normalize how far the wheel was spun (or trackpad dragged). This is super useful for zoom support where you want to throw away the chunky scroll steps on the PC and make those equal to the slow and smooth tiny steps on the Mac. Key data: This code tries to resolve a single slow step on a wheel to 1.

• pixel is normalizing the desired scroll delta in pixel units. You'll get the crazy differences between browsers, but at least it'll be in pixels!

• positive value indicates scrolling DOWN/RIGHT, negative UP/LEFT. This should translate to positive value zooming IN, negative zooming OUT. This matches the newer 'wheel' event.

Why are there spinX, spinY (or pixels)?

• spinX is a 2-finger side drag on the trackpad, and a shift + wheel turn with a mouse. It results in side-scrolling in the browser by default.

• spinY is what you expect -- it's the classic axis of a mouse wheel.

• I dropped spinZ/pixelZ. It is supported by the DOM 3 'wheel' event and probably is by browsers in conjunction with fancy 3D controllers .. but you know.

Implementation info:

Examples of 'wheel' event if you scroll slowly (down) by one step with an average mouse:

OS X + Chrome (mouse) - 4 pixel delta (wheelDelta -120) OS X + Safari (mouse) - N/A pixel delta (wheelDelta -12) OS X + Firefox (mouse) - 0.1 line delta (wheelDelta N/A) Win8 + Chrome (mouse) - 100 pixel delta (wheelDelta -120) Win8 + Firefox (mouse) - 3 line delta (wheelDelta -120)

On the trackpad:

OS X + Chrome (trackpad) - 2 pixel delta (wheelDelta -6) OS X + Firefox (trackpad) - 1 pixel delta (wheelDelta N/A)

On other/older browsers.. it's more complicated as there can be multiple and also missing delta values.

The 'wheel' event is more standard:

http://www.w3.org/TR/DOM-Level-3-Events/#events-wheelevents

The basics is that it includes a unit, deltaMode (pixels, lines, pages), and deltaX, deltaY and deltaZ. Some browsers provide other values to maintain backward compatibility with older events. Those other values help us better normalize spin speed. Example of what the browsers provide:

                     | event.wheelDelta | event.detail
   ------------------+------------------+--------------
     Safari v5/OS X  |       -120       |       0
     Safari v5/Win7  |       -120       |       0
    Chrome v17/OS X  |       -120       |       0
    Chrome v17/Win7  |       -120       |       0
           IE9/Win7  |       -120       |   undefined
    Firefox v4/OS X  |     undefined    |       1
    Firefox v4/Win7  |     undefined    |       3

Kind: inner method of normalizeWheel

NumberUtils

A collection of Number related utilities

• NumberUtils
  • ~lerpNumber(v0, v1, t) ⇒ Number
  • ~range(oldValue, oldMin, oldMax, newMin, newMax, clamped)
  • ~clamp(value, min, max) ⇒ Number
  • ~map(value, min, max)
  • ~angleDistance(alpha, beta)
  • ~angleDistanceSign(alpha, beta)
  • ~smoothstep(min, max, value) ⇒ Number
  • ~mix(value1, value2, percent)
  • ~sign(value) ⇒ Number
  • ~randByPower(min, max, power, [rd])
  • ~mapToPower(value, min, max, power)
  • ~distance(x1, y1, x2, y2) ⇒ Number
  • ~distanceCompare(x1, y1, x2, y2) ⇒ Number

NumberUtils~lerpNumber(v0, v1, t) ⇒ Number

Linearly interpolates a Number

Kind: inner method of NumberUtils
Returns: Number - Interpolation between v0 and v1 based on t

NumberUtils~range(oldValue, oldMin, oldMax, newMin, newMax, clamped)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~clamp(value, min, max) ⇒ Number

Clamps a value between min and max values

Kind: inner method of NumberUtils
Returns: Number - A number clamped between min and max

NumberUtils~map(value, min, max)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~angleDistance(alpha, beta)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~angleDistanceSign(alpha, beta)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~smoothstep(min, max, value) ⇒ Number

Smoothstep implementation. https://en.wikipedia.org/wiki/Smoothstep

Kind: inner method of NumberUtils
Returns: Number - Value of the interpolation

NumberUtils~mix(value1, value2, percent)

Similar to linear interpolation.

Kind: inner method of NumberUtils

NumberUtils~sign(value) ⇒ Number

Returns the sign of a number in -1,0,1 form.

Kind: inner method of NumberUtils
Returns: Number - 0 if value is zero, -1 if value is less than 0, 1 otherwise

NumberUtils~randByPower(min, max, power, rd)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~mapToPower(value, min, max, power)

TODO: Documentation

Kind: inner method of NumberUtils

NumberUtils~distance(x1, y1, x2, y2) ⇒ Number

Computes distance between two points in 2D space.

Kind: inner method of NumberUtils
Returns: Number - Distance between x1,y1 and x2,y2

NumberUtils~distanceCompare(x1, y1, x2, y2) ⇒ Number

Not a real distance calculation. Useful to sort objects by distance ( much faster because no sqrt )

Kind: inner method of NumberUtils
Returns: Number - bogus distance between x1,y1 and x2,y2. DO NOT USE WHEN A REAL DISTANCE IS NEEDED

ObjectUtils

A collection of Object related utilities

ObjectUtils~isPlainObject(o) ⇒ Boolean

Determines if the object has been constructed using javascript generic {} syntax

Kind: inner method of ObjectUtils
Returns: Boolean - true if the object is a plain object, false otherwise.

Platform

Holds information on the Platform where this code is run

Properties

VueUtils

A collection of Vue.js related utilities

VueUtils~defineReactive(value, model)

Allows to define a set of reactive properties of "value" (Object) by looking into "model" (Object) and comparing the two

Kind: inner method of VueUtils

ElasticNumber

Kind: global class
Properties

• ElasticNumber
  • new ElasticNumber()
  • .update(delta)

new ElasticNumber()

An Utility class that allows to tween a numeric value (target) into a smoothed value (value)

Example

constructor () {
 this.myNumber = new ElasticNumber();
 this.time = new Date().getTime()
}

onUpdate () {
 const now = new Date().getTime()
 const delta = now - this.time
 this.myNumber.target = Math.random() * 100
 this.myNumber.update(delta);

 this.mySprite.x = this.myNumber.value
 this.time = now
}

ElasticNumber.update(delta)

Updates the ElasticNumber on tick. Value will be updated from target.

Kind: static method of ElasticNumber

Gyroscope

Kind: global class
Properties

new Gyroscope()

An utility singleton that returns a device's Gyroscope data in the form of orientationX and orientationY.

The values are updated every frame and the system stops updating if it determines that the device does not have gyroscope capabilities.

RAF

Kind: global class

• RAF
  • new RAF()
  • .add(listener)
  • .remove(listener)

new RAF()

An utility singleton that holds all requestAnimationFrame subscribers and calls them in sequence each frame.

Example

import RAF from 'js-utils'

constructor () {
 RAF.add(this.onUpdate)
}

onUpdate () {
 // do stuff
}

onDestroy () {
 RAF.remove(this.onUpdate)
}

raF.add(listener)

Adds a subscriber to be called at each requestAnimationFrame

Kind: instance method of RAF

raF.remove(listener)

Removes a subscriber from requestAnimationFrame

Kind: instance method of RAF

LICENSE

Copyright (c) 2020, MONOGRID S.R.L.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.