[udig-devel] Several spatial operations are needed

["Vitali Diatchkov" <vitali@xxxxxxxxxxxx>]

Hello!

We are going to implement several bulk spatial operations needed in one
project.
May be there is existing implementation of algorithms using JTS
functionality (for binary spatial operations) and GeoTools stuff to
manipulate features.

1) Division of the layer with a set of polygonal features (like polygonal
coverage) by the specified polygon (an argument).
Input - FeatureStore with polygonal features, Polygon (one or more)

Each Feature from FeatureStore{
	if(Feature intersects with Polygon){
		Divide a Feature geometry by Polygon boundaries into
parcels;
		From each parcel create a feature and write to the output;
	}else{
		Write a Feature to the output without modifications;
	}

}

So , features are divided by polygon boundary into parcels, nothing more
special.

2)Cutting of the set of features by a polygon (a mask). Cut everything from
feature geometry that is outside of the mask polygon and write modified
feature. What is the right name of the spatial operation..

3) There is polygonal coverage of features with topology consistency. The
required operation analyzes every feature and depending on the condition
merges the feature to one of the neighboring features with topology
preserving. If the coverage is initially topologically consistent, then no
problems using JTS stuff in binary context (between two geometries) cause
during merging new vertices are not created.


Those operations are intended to be integrated for UDIG. We would like not
to invent a wheel whereas there is an implemented things.

Vitali Diatchkov.