quick-loader

quick-loader is an asset loader that loads everything. Say you have some third party libraries with their own loader modules, you can pipe the loading progress into quick-loader's loading pipeline. It also does basic loading for image, json, jsonp, text, video and audio.

Usage

Simple batch loading

Add several assets to the loader and get the percent of the batch loading.

// assuming you are using CommonJS
var quickLoader = require('quick-loader');

// load the asset with certain type
quickLoader.add('1.jpg', {type: 'image'});

// or let it guess the type by the url extension
quickLoader.add('2.jpg');

// you can also define the weight of the asset which is 1 by default
quickLoader.add('3.jpg', {weight: 2});

quickLoader.start(function(percent){
    
    // assuming the files are loaded in the same order as above
    // it will log 0.25, 0.5, 1.0
    console.log(percent);
    
    if(percent === 1) {
        init();
        
        // the listener was removed at this point and it
        // will not have any stacked async issue so you can
        // load something else again.
        quickLoader.add(...);
        quickLoader.start(...);
    }

});

Individual asset callback

You can add an onLoad callback to an individual asset.

quickLoader.add('data.json', {
    onLoad: function(data) {
        console.log(data);
    }
});
quickLoader.add('img.jpg');
quickLoader.start(...);

Load a single item out of the quick-loader pipeline

For all feature that works with Batch loading, it works with individual asset loading as well. Basically all you need is to change the add() into load()

quickLoader.load('data.json', {
    onLoad: function(data) {
        console.log(data);
    }
});

Initial content

Sometimes when you add the loading query to the batch loader, you want to have access to the asset instance immediately. This feature only works with asset types: image, video and audio

var img = quickLoader.add('img.jpg').content;

quickLoader.start(...);

No Cache

Normally after an item is loaded, the content will be stored and if you fetch the same url, it will not download the content again. But you can set noCache to true in the item config and bypass this feature. It will remove the reference after the file is loaded.

quickLoader.load('img.jpg', {
    noCache: true
});

Working with third-party library loader like THREE.JS JSON Loader

quickLoader.load('mesh.json', {
    
    type: 'any',
    
    loadFunc: function(url, cb, loadingSignal) {
        
        var loader = new THREE.JSONLoader();
        
        loader.load( url, function( geometry, material ) {
            var mesh = new THREE.Mesh( geometry, material);
            
            // tell quickLoader the item is loaded and
            // store the mesh instead as content
            cb(mesh);
        });
    }
});

Postprocessing

You can do postprocessing work with onPost

quickLoader.load('data.json', {
    type: 'json',
    postWeightRatio: 0.2 // [0-1] default 0.1, the weight ratio to the actual weight
    onPost: function(content, postLoadingSignal) {
    	content.foo = 'bar';
    	postLoadingSignal.dispatch(1); // complete
    }
});

Individual asset preloading

You can also add listener to the individual asset. This feature only works with asset types json, text and any.

quickLoader.add('data.json', {
    type: 'json',
    weight: 5,
    hasLoading: true,
    onLoading: function(percent){
        console.log(percent);   
    }
});

Individual asset preloading with third-party library

This following example is to show you when you are using any asset type, you can do whatever you want.

quickLoader.add('a_fake_loader', {
    type: 'any',
    weight: 50,
    hasLoading: true,
    onLoading: function(percent) {
        console.log('loading: ' + ~~(percent * 100) + '%');
    },
    onLoad: function(content) {
        // some content here
        console.log('loaded: ' + content);
    },
    loadFunc: function(url, cb, loadingSignal) {
        var count = 0;
        var interval = setInterval(function(){
            count++;
            loadingSignal.dispatch(count / 10);
            if(count == 10) {
                clearInterval(interval);
                cb('some content here');
            }
        }, 100);
    }
});

Add a chunk of assets

quickLoader.addChunk(['1.jpg', '2.jpg', '3.jpg'], 'image');

// let quick-loader to guess the types
quickLoader.addChunk(['1.jpg', '2.txt', '3.json']);

Add DOM Images(experimental)

It adds all images through img tag and background images.

quickLoader.addChunk(document.body.querySelectorAll('*'));

Multi-batch Loader instances

For some reason if you want to have 2 loaders, you can create a new one like this:

var quickLoader = require('quick-loader');

var batchLoader = quickLoader.create();
batchLoader.add(...);

Cross Origin

var quickLoader = require('quick-loader');

// set for everything cross-origin within a domain
quickLoader.setCrossOrigin('http://mydomain/', 'anonymous')

// set cross-origin for individual load item
quickLoader.add('http://anotherdomain/image.jpg', {
  crossOrigin: 'anonymous'
})

Installation

Download the standalone version HERE

npm install quick-loader

License

MIT License