mini-gl

A small webgl2 library to edit images and apply filters.

Inspired and partially based on glfx.js by Evan Wallace

Note: the library adopts a sRGB correct workflow. Keep in mind if adding new shaders/ filters.

Current "filters"

• lights: brightness, exposure, gamma, contrast, shadows, highlights, bloom
• colors: temperature, tint, vibrance, saturation, sepia
• effects: clarity/ sharpness, noise reduction, vignette
• color curves
• insta filters
• image blender
• bokeh/lens and gaussian blur
• perspective correction
• translate-rotate-scale matrix

Small demo https://codepen.io/xdadda/pen/ogxOzQP Full demo https://mini2-photo-editor.netlify.app (src https://github.com/xdadda/mini-photo-editor)

Setup

Install: npm i @xdadda/mini-gl

Import in js:

import { minigl} from '@xdadda/mini-gl'

Constructor

      const _wgl = minigl(canvas,image,colorspace)

• canvas: is the destination HTMLCanvasElement on which minigl will render the image
• image: is the source HTMLImageElement with the original image
• colorspace: specifies the color space of the rendering context ('srg'|'display-p3'); the image's colorspace can be extracted from the file's ICC profile metadata (@xdadda/mini-exif)

Render chain

1. Load original image texture in memory

      _wgl.loadimage()

2. Apply filters (one or more as required)

      // TRANSLATE/ROTATE/SCALE filter
      // input: {translateX:0,translateY:0,angle:0,scale:0,flipv:0,fliph:0}
      // where scale:0 is 1:1 scale
      _wgl.filterMatrix({translateX:0,translateY:0,angle:0,scale:0,flipv:0,fliph:0})

      // BASIC ADJUSTMENTS filter
      // input: {brightness:0, clarity:0, contrast:0, exposure:0, gamma:0, gray:0, 
      //        saturation:0, sepia:0, temperature:0, tint:0, vibrance:0, vignette:0}
      _wgl.filterAdjustments({...})

      // BLOOM filter
      // input: strength
      _wgl.filterBloom(0.5)

      // NOISE filter
      // input: strength
      _wgl.filterNoise(0.5)

      // HIGHLIGHTS & SHADOWS filter
      // input: highlights_strength, shadows_strength
      _wgl.filterHighlightsShadows(0.2,0.3)

      // CURVES filter
      // input: Array of 'curves' for RGB/Luminance, RED, GREEN, BLUE
      // where a 'curve' is an array of points (x,y) across which a spline is interpolated
      // (x,y) represent the value mapping, from x to y
      // a 'curve' can be null to signify a linear interpolation
      // linear input example: [ [[0,0],[0.25,0.25],[0.75,0.75],[1,1]], [...], null, null ]
      _wgl.filterCurves([ [...], [...], [...], [...] ])

3. Draw to canvas

      _wgl.paintCanvas()

Other functions

Destroy textures and clear memory:

_wgl.destroy()

Generate an Image element from the current render:

_wgl.captureImage()

Crop image:

_wgl.crop({left, top, width, height})

Clear crop and restore original image:

_wgl.resetCrop()

Resize image:

_wgl.resize({left, top, width, height})

Clear resize and restore original image:

_wgl.resetResize()