[PD] data-s with math inside (feature request?)

[Mathieu Bouchard]

On Thu, 6 Jul 2006, Frank Barknecht wrote:

> As I see it, this is another case where some way to detect changes of 
> data in a ds-instance would help a great deal. There already is the 
> starting for this available with the [struct] object's outlet, that 
> sends a pointer, if an instance is selected in Edit mode. One could do 
> all math or list or symbol processing that Pd is capable of with this 
> pointer using normal Pd objects. However there still is no way to detect 
> a change outside of edit mode and no way to detect changes through other 
> means (though these originate somewhere in Pd anyways and thus they can 
> be intercepted from there.)

I want this *and* the ability to make custom renderers for those 
structures. I mean, one should be able to make an abstraction that plays 
the same role as [drawpolygon] yet uses [drawpolygon] as its 
implementation, so that e.g. if I want to draw stuff in polar or log 
coords (or anything else) I don't have to store both the "internal 
coordinates" and the "apparent coordinates" in the object. The system 
should also allow structures to respond to clicks in a user-defined way 
which could be included in [drawpolygon]-like abstractions, or as a 
separate object.

Those are again the same MVC ideas as developed at XEROX-PARC in the 
1970's and which are getting popular in GUI design and web design these 
years (finally).

A way of detecting changes is central to MVC and is called 
Observable/Observer or Publish/Subscribe. However, MVC is more than just 
that.

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| Mathieu Bouchard - tél:+1.514.383.3801 - http://artengine.ca/matju
| Freelance Digital Arts Engineer, Montréal QC Canada