Further to my previous email I am now trying to plot data using
only WFS layers and a few issues / feature requests / bugs have
come to light, hopefully the images attached will help illustrate
and someone can point me in the right direction...
Snapping to points on any layer
this is great but is it possible to show all the nodes on the map
so I can see what I'm snapping to before I click the mouse
button? Image 1 (attached) shows a curved line in my base data
that I want to snap to. (The circle is the cursor, no idea why
the crosshair didn't get captured in the screen dump?!?!) Image 2
shows the same line highlighted for editing so that I can see
where the nodes are. I would like to see this without having to
select it for editing, is this possible? Would it also be
possible to show which node will be snapped before the mouse
button is clicked?
Doing more than just providing a circle is extremely difficult
simply because the data must be loaded from the data source which
is a slow process. Loading the entire layer is prohibitive because
it is difficult to know how much information you might get when you
try to do the load. We try to keep as little in memory as
possible. I have found that even with the current editing
framework it requires a great deal of memory. Loading more would
cause serious problems. So I'm afraid that it is kind of up to the
user to try to figure it out. What can be done is the line can be
editing after the fact by moving the vertex again.
Seems to be some confusion on this one, what I'm asking for is the
ability to show the nodes on a layer. Only the loaded part of the
layer and surely the nodes must have been loaded into memory in
order to render it in the first place? It would be nice if when
snapping the closest node to the cursor could be highlighted but
that's less essential than showing the nodes in the first place.
Maybe this is already possible with styles?
Yes of course the features are rendered but sometimes the view can
contain a massive amount of information. Consider a shapefile
millions of features and you are zoomed out to the whole world. You
probably don't want all of that in memory. So how do you know when
to keep things in memory. One thing we've considered is to provide
the option to 1. Load a layer into memory and 2. be able to load a
portion of a layer into memory. If the user activates one of those
mode then this would be possible. (This isn't implemented yet).
[...]
when can we expect a release based on Geo-Tools 2.4 as per my
previous email? I'm hoping that will mean I can load the base
table data direct from Oracle instead of through WFS which would
presumably make it faster?
It will be a little while as there were some significant API change
from Geotools 2.2. and 2.4. We've got it running but there are still
bugs and some of the styling work is still requires some repair.
Jesse
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