RE: Draft WebAudio API review text

Hi there.  As someone who has dug my fingers into working the Web Audio API
quite a bit, and having given a talk at the end of last year related to
this at EmpireJS (,
I would first like to express that I greatly appreciate how thorough and
on-point this feedback document is.  I wanted to highlight some of the
points that I most strongly agree with as well as some feedback & humble
suggestions that came to mind.

1) Constructibility

I completely agree that constructability of the AudioNodes would be a huge
win for making Web Audio more naturally expressible in JS.  As for the two
options that you propose in your code snippets, the second is more
compelling to me as it is far less verbose and a pattern that is commonly
seen and used in JS.

// An alternative that provides the context via the PannerNode ctor:
AudioContext.prototype.createPanner = function() {
    return new PannerNode({ context: this });

One of the things that I DO appreciate about the current specification,
however, is that because of it's restrictiveness (nodes can ONLY be
produced from an AudioContext), nodes are ensured to ALWAYS be linked to an
AudioContext and will never be zombie nodes.  I think that defining the
context as just another parameter in the instantiation object de-emphasizes
this and new users may easily neglect to define the context if they choose
to use constructors.  I think it would be clearer, and express a separation
of concerns, to have something like this instead:

var panner = new PannerNode(context, { panningModel: "equalpower", ... })

The definition of the context is up-front and explicit to users and
separates its assignment from the other node-specific parameters which

Also, are you also proposing here that I would be able to do something like
the following?

context.createPanner({ panningModel: "equalpower", ... });

If not, this would be more consistent/powerful in my opinion.

2) ScriptProcessorNode improvements & "De-sugaring" the *Node Types (+ test
YES & YES +1000

3) Default context

I agree that there is much ambiguity around the idea of a "default context"
and the interoperability between the <audio> element and the Web Audio API.
 Clarification and access/clarity around the "default context" would help
not only implementers to be consistent, but also help users to understand
the relationship between the Web Audio API and the other parts of the web

4) AudioNode connect chaining

[Why doesn't AudioNode::connect() return the passed AudioNode destination?]
I agree 100% with this.  Connecting nodes into an audio graph is VERY
verbose and manual which also makes it easy to miss a connection in the
graph.  Being able to chain would allow users to connect full paths which
is far more expressive.

5) Parameters for connecting in/out

I actually disagree on this point.  Adding parameters for connecting in/out
nodes would provide multiple ways to connect the graph, which I think is
unnecessary and will make it easy to connect up a graph incorrectly.  It is
much clearer to create all of the nodes then build it explicitly with
..connect.  If the connect methods are chainable as you propose, this would
be sufficiently expressive to eliminate much of the pain/overhead of
connecting up a graph that exists in the current specification.

Also, if you are also proposing something like: context.createPanner({
panningModel: "equalpower", ... }); (as I mentioned above)
it would be far too cluttered to also add in in/out parameters into this
mix and be more confusing than useful in my opinion.


Received on Friday, 19 July 2013 02:12:25 UTC