Skip to content

Latest commit

 

History

History
121 lines (92 loc) · 6.34 KB

README.md

File metadata and controls

121 lines (92 loc) · 6.34 KB
Raw

Vue-pattern-placeholder

This plugin provides a placeholder component for Vue.js. It uses canvas to render patterns from input string like URL.

NPM version Dependencies Maintenance PRs Welcome MIT license

Table of contents

Demo

Sample images

Recent updates

  • 2019-05-04 Import format changed, refer to usage section.

Installation

To install this plugin, open terminal in your Vue project directory and type:

npm i --save-dev vue-pattern-placeholder

This command will install the plugin in your project node_modules dir and add it as a project development dependency in project's package.json file.

If you need this plugin as a generic dependency, type this command instead:

npm i --save-dev vue-pattern-placeholder

Usage

To import a component, write:

import patternPlaceholder from 'vue-pattern-placeholder'

Add it to the components property

components: {
    patternPlaceholder
},

Now you can use it in your template:

<patternPlaceholder
  :width="150" :height="150"
  :input="''+item_data.media_id"
  label="150x150"
  label_style="900 30px Arial" label_color="#000"
  :hue_range="[70, 170]"
  :lightness_range="[0, 100]"
/>

I recommend to start playing with hue_range and lightness_range properties to reach the best look.

API

For now, none of the parameters are required.

Option Data-type(s) Description Default
width Number width of an image 250
height Number height of an image 250
input String this text will be converted to a pattern Hi there! :-)
label String text label to show No label
label_style String canvas font style. Example: 900 30px Arial 20px Helvetica bold
label_color String color of a label. Example: #777 #777
metric String metric, used to create a pattern. Examples: Euclidean, Manhattan, Minkovski Manhattan
debug Boolean allows to show center points for a Voronoi pattern false
hue_range Array sets a color range in degrees. Example: [0, 359] [0, 359]
lightness_range Array lightness range for pattern pieces in percents. Example: [0, 100] [0, 100]

Warning

Please be aware that this project is still in a testing stage. Use at your own risk. Ideas and bug reports are welcome.

Inspiration

I thought about converting text to an image and I remembered Voronoi patterns: these are easy to implement and look very nice.

Voronoi pattern animation

Then I had an idea:

  • take a string, process it using a SHA-256 hash function
  • extract hash bytes
  • use pairs of bytes, converting each to a float value between 0 and 1 to place X and Y points
  • count pattern segments, use numbers to set each one's hue in HSV color palette
  • calculate pattern areas
  • use areas to determine lightness of a pattern segment in HSV

TODO

  • Overlay text
  • Fix wrong color representation in overlay text
  • Autoreload fix (probably needs a destructor)
  • Fix empty canvas on width / height change
  • Fixed beforeDestroy bug
  • Added demo
  • Consider integrating label style and color into one parameter
  • Label style settings in key-value format
  • Extend hue setting to a list of several possible hues

Acknowledgements

Thanks to AnatolV from RosettaCode for a nice Voronoi diagram implementation.

Thanks to emn178 for js-sha256 library. It is easy to use and helps a lot.