[Gegl-developer] DAGs make users' eyes cross

[hendrik at topoi.pooq.com]

On Tue, Oct 17, 2006 at 03:55:56PM +0000, Ken Bateman wrote:
> I've independently been thinking of a similar imaging core for the last month or
> so.  Of course, I think it's a good idea.  Logically, behind the scenes,
> everything should be in the form of a DAG.  But I think that a raw DAG does not
> make up a part of a good user interface.  
> 
> Spreadsheets are in essence a DAG for performing numerical calculations, and I
> would suggest that the user interface should take the form of a spreadsheet
> since this is a model familiar to many users.   Some cells would contain source
> rasters, other cells would contain paths, vector graphics, or masks (or even
> references to other functions), some cells would contain a function that
> referred to other cells for inputs, some cells could contain labels or comments,
> and most cells would be empty.

The spreadsheet user interface is most useful when the data 
naturally fits into arrays.  
For many everyday applications, this is the case.
I don't see it for graphics, unless you are actually talking about a 
mosaic.

If you ignore the conventional meaning of the word "cell" in the above, 
though, what you have is very like a programming language.  The traditional 
UI for a programming language has been ASCII text.

For a different one try a tree structure with crossreferences to labelled 
branches.  Something like that has been done for the scripting language in 
some popular war game -- I'm not sure I ever knew which.

-- hendrik