Re: user-defined color tables; cross sections

Hi Doug, hi all,

> I'd like to have a set of pre-defined color tables (e.g. rainbow,
> reverse rainbow, earth...) from which a user can choose. Has anybody
> done anything like this with VisAD?
> 
I've got a few color tables I've put together in "all these years"
working with VisAD. 

> I thought about taking a file-based approach where a ColorTable class
> could open/save color tables from/to files with some human
> readable/editable format.
> 
If you mean "ascii" when your say "human readable/editable format", then
I've got some code that does that. 
I defined the table like:

17 // table length
Urban, Forest, Wheat, Maize,...  // String[] for class names; not always
used
1.0 0.0 0.0
0.8 0.4 0.0
0.6 0.2 0.0
0.6 0.4 0.0     // RGB values
0.6 0.0 0.0
0.8 0.6 0.0
1.0 1.0 0.0
...
> On the other hand, I'd rather avoid the baggage of more files to carry
> around. I thought of a ColorTable class with static ColorTables (akin to
> RealType.Longitude). I could then extend ColorTable to make MyColorTable
> which could define some more static ColorTables with or without using
> files.
> 
As said before, I've got a class, but I haven't finished work on that,
and there are tables not implemented yet. Furthermore, the code that
reads the file described above is not included.
> Any thoughts?
> 
> Are there other "standard" color tables in the vis community that could
> be adapted to VisAD?
> 

I can only think of tables with reduced length (so one clearly sees a
few levels), which I find very useful. Another pretty table is the one
used for altitude, which I also have and would be glad to donate.
Feel free to ask for the code.

Cheers,

Ugo