[Geotools-devel] Re: R: RE: Spatial indexes in JTS

[Jody G. <jga...@re...>]

Martin Davis wrote:

>Hmmm...  Jody, your suggestion must have flashed past without
>registering.  Perhaps at the time I was focussed on other things.
>  
>
No prob - at the time we wanted some (any) feedback from the community 
before changing things.
Sounds like we are getting the feedback this week.

>I'm thinking that the best thing to do is to extend the
>CoordinateSequence interface with only the functions that are required
>to allow JTS to work efficiently with user-defined implementations (e.g.
>to provide some of the more common and simpler functions as simple scans
>of the coordinate sequence).  If further functionality is required (as
>in your case) the client can easily extend the basic interface.
>  
>
Actually what you have bellow is perfect - nobody ended up using any 
kinds of attributes other than doubles.
(The other thing CoordinateSequence needed to provide client code to 
work with user-defined
CoordinateSequence implementations - and you improved interface provides 
that).

>So the improved CoordinateSequence interface would look like:
>
>interface CoordinateSequence
>{
>	size();
>	public Coordinate getCoordinate();
>	public Coordinate[] getCoordinateArray();
>	public Object clone();
>	
>	// new methods
>
>	public int getDimension();
>	public double getOrdinate(int index, int ordinate);
>	public double getX(int index);
>	public double getY(int index);
>	public double getZ(int index);
>}
>
>Does that work for everybody?
>  
>
I think so - I am afraid I don't have all the code in  my head anymore. 
Here let me think ...

The only thing to check is CoordinateSequenceFactory:
- we needed to tell the Dimension of a Geometry, not all Geometry 
classes allowed access to a CoordinateSequence, was the reason the 
CoordinateSequenceFactory extention mentioned in the last email.
- oh and I suppose we need to change CoordinateSequenceFactory so users 
can specify their additional ordiantes

So something like the following:
interface CoordinateSequence {
   CoordinateSequence create( Coordinate arg );
   CoordianteSequecne create( double[] xyz[] );
    int getDimension();
}

Thanks Martin, that is all I can think of (and I need to get back to work).

Jody