var viewer = new BimSurfer();

// Alternative 1: Load a model from an on-line BIMserver with existing bimserverapi/model:
var bimServerApi = ...// existing bimserverapi
var model = ...// existing bimserverapi model
var viewerModel = viewer.load({bimserverapi: bimserverapi, model: model, query: …});

// Alternative 2: Let bimsurfer create a bimsererapi and model
// The load()'ing of a model happens asynchronously. Hence, it
// returns a Promise with a then() function that accepts a 
// method in case of success and (optionally) in case of error.
viewer.load({bimserver: …, username: …, password: …,
             poid: …, roid: …, query: …}).then(
    function(model) { … },
    function(error) { … }
);

// Alternatively 3: load a model from file:
var model = viewer.load({url: "/path/to/file.glTF"}).then(function(model) {

// getTree() returns a javascript notation of the tree.
// `guid` and `nlevels` allow to only return a subset 
// of the tree for performance reasons.
var tree = model.getTree({guid: …, nlevels: …}).then(function(tree) {

// Creating a DOM tree is framework specific, but examples
// are provided for various frameworks [1]
// [1] https://github.com/opensourceBIM/bimvie.ws-viewer/
//             blob/master/index.html#L108
var domtree = …;

domtree.on("click", function(oid) {
    viewer.viewFit({ids: [oid]});
});

domtree.on("eye-click", function(oid) {
    viewer.hide([oid]);
});

// Event handlers on the viewer can be subscribed to using the 
// on() method.

function selectionChanged(currentlySelected, selectionChanged) {

}

viewer.on("selection-changed", selectionChanged);

// Event handler can be canceled using the off() method. Possibly
// by using a wildcard to cancel all handlers on a particular
// event.
viewer.off("selection-changed", selectionChanged);
viewer.off("selection-changed", "*");

var viewer = BimSurfer.Viewer();
// Still not so sure what to do with this
var tree_view = BimSurfer.DojoTreeView();
var canvas = BimSurfer.XeoEngineViewer();
var loader = BimSurfer.BimServerLoader();
var query = BimSurfer.RubenQueryEngine();
var painter = BimSurfer.MaterialColorByEntity();

viewer.addTreeView(tree_view);
viewer.addViewer(canvas);
viewer.addLoader(loader);
viewer.setPainter(painter);

loader.load({bimserver: …, username: …, password: …,
             poid: …, roid: …, query: …});