Re: [Geotools-devel] geotools tools

[Martin D. <mar...@te...>]

Hello


Cameron Shorter wrote:
> I'm thinking that we should have a Tools interface similar to the geotools1 
> project, but I'm not sure if that will fit in with the advanced features of 
> java.  I notice that the ZoomMap example is using JDK features for zooming.
> 
> Do the tools deserve their own module, or should they be incorporated 
> into another module.  If so, which one?

A own module seems to make sense. However, the current ZoomPane already 
provide a limited set of feature. We could:

   1) Refactor ZoomPane and its internal tools (MouseReshapeTracker and
      MouseSelectionTracker) in an other package. I'm totally open to
      refactor it if peoples feels we should.

   2) Add new tools straight into the current org.geotools.swing.gui
      package, maybe with package-private access in order to keep the
      API light.

   3) Any other suggestion?



> Typical Tools required:
> --------------------------
> Click and Drag Zoom In/Out
> One Click Zoom In/Out
> Pan

Current ZoomPane support "Click and Drag zoom in". The default
implementation doesn't provide "One click Zoom in/out", but it
provides "Mouse wheel zoom in/out". One click zoom in/out would
be esay to implement if we want it.


> 
> Enter a Point
>   Click to enter a point.
> 
> Enter a Line
>   Left Click to enter first or another point
>   Right Click to enter last point
> 
> Enter a Shape
>   Similar to entering a line.

Already implemented (not exactly that way but close) in ZoomPane:

   1) Create a ZoomPane subclass.

   2) Override 'Shape getMouseSelectionShape(Point2D point)'.
      This method is automatically invoked when the user start
      dragging. The 'point' argument is the logical coordinate
      (not the pixel coordinate), so you can returns an arbitrary
      shape (line, rectangle, ellipse, arrow or whatever) based
      on user coordinates.

   3) Override 'void mouseSelectionPerformed(final Shape area)'.
      This method is automatically invoked when the user finish
      dragging. ZoomPane subclass could store the selected
      coordinates there.


> Select a feature on hover
> Select a feature on click
> 
> Edit a Line or Shape.
>   Select the features
>   Select a point within the shape
>   Delete the point and merge the line or
>   Split the line into two or
>   Split the shape into two or
>   Move the point
> 
>   Select a line within a feature
>   Add another point on the line


ZoomPane provides no support for this. But we could add them to a 
ZoomPane subclasses for example, or create a tools package.

	Regards,

		Martin.