What exactly would "this" (#4) look like in Pd?

-Jonathan

--- On Wed, 12/15/10, brandon zeeb <zeeb.bran...@gmail.com> wrote:

From: brandon zeeb <zeeb.bran...@gmail.com>
Subject: Re: [PD] PD OOP?
To: "PD List" <pd-list@iem.at>
Date: Wednesday, December 15, 2010, 1:51 PM

In my experience with emulating OOP in Pd I've had moderate success.  As a Java 
developer by day, I find myself attempting to recreate familiar patterns within 
Pd (ie: usually IoC and Flyweight in Pd).   Main problems with recreating OOP 
in Pd are the following:

Everything is globalNo control over abstraction (object) construction order and 
lifecycleNo introspection (although not required, very helpful, and don't tell 
me it's in some external, I don't care!)
No concept of "this"No interfaces or abstract abstractions (to control inlet 
patterns)Unfriendly and inconsistent type system (it is cumbersome in real use, 
although I get over this by using [list])
and on and onIn most Pd patches, I see people using a few lookup tables again 
and again (ie: mtof).  As this is a complete waste of memory, one can attempt 
the Flyweight pattern.  However, doing so in Pd is a very dangerous game, as 
you will have NO idea which abstraction first created the table and thus have 
no control over retaining access to it.  In my library I've dropped this 
approach in favor of something closer to IoC.


Basic IoC is very possible, and indeed very rewarding.  Very often I pass in 
other abstractions as object creation arguments.  The most simple example of 
this in my library is my [bypass~] abstraction used to dynamically enable and 
disable a given abstraction.  I use this EVERYWHERE to save CPU cycles in 
combination with another object to programmatically disable the sub-abstraction 
when the user selects a given value (ie: when the filter cutoff is at MAX with 
no resonance, disable the filter).


In use:

[bypass~ some_process~ 330 1 3 9]

Where [bypass~] expects it's 1st argument to be an abstraction and the next 10 
to be arguments to that abstraction.  Every patch which uses [bypass]~ must 
have 1 signal inlet and 1 event inlet.  Unfortunately, this interface can't be 
programmatically enforced. [bypass~] passes it's 1st two inlets to the 
sub-abstraction, while the 3rd is used to control [bypass~]


I've attached [bypass~] and it's dependencies, have fun!

~Brandon


-----Inline Attachment Follows-----

_______________________________________________
Pd-list@iem.at mailing list
UNSUBSCRIBE and account-management -> 
http://lists.puredata.info/listinfo/pd-list



      
_______________________________________________
Pd-list@iem.at mailing list
UNSUBSCRIBE and account-management -> 
http://lists.puredata.info/listinfo/pd-list

Reply via email to