jam/js/rtree

#rTree

A non-recursive R-Tree library in pure JavaScript with no dependencies. Fork of Jon-Carlos Rivera's fantastic library which sadly seems not to be maintained. MIT Licensed.

##So far:

• Bug fix when deleting points.
• Common.js module.
• Updated tests.
• Factory function for constructor.
• Method for dealing with GeoJSON.
• All methods now accept callbacks.
• Query by bbox instead of rectangle.
• Submit to NPM.
• Update examples.
• add closure
• add GruntFile
• fix syntax (make it pass jslint)
• more modular
• that bug with deleting

##API

• RTree ( [ Number max_node_width, Function callback ] )

###Parameters:

• max_node_width : optional : The maximum width of a node before a split is performed¹.

###Returns:

• An empty rTree object.

###Usage:

• Make a new rTree with a max node width of 10:
• var myRTree = RTree(10);

##rTree.insert

• rTree.insert ( Rectangle³ bounds, Object element)

###Parameters:

• bounds : required : A minimally bounding box for element.
• element : required : An object to add to the R-Tree.

###Returns:

• True.

###Usage:

• Insert a 10x10 object that starts at position 10x10:
• myRTree.insert({x:10, y:10, w:10, h:10}, myObject);

##rTree.remove

• rTree.remove ( Rectangle³ area _[, Object element)

###Parameters:

• area : required : An area to search within.
• element : optional : An object to remove from the R-Tree. If no object is specified, all elements that touch area are deleted.

###Returns:

• An array of leafs deleted from the R-Tree.

###Usage:

• Deletes all object that touch the 10x10 rectangle starting at position 10x10:
• var myDelCount = myRTree.delete({x:10, y:10, w:10, h:10});
• Delete only specific object if it touches the 10x10 rectangle starting at position 10x10:
• var myDelCount = myRTree.delete({x:10, y:10, w:10, h:10}, specific_object);

##rTree.geoJSON:

• rTree.geoJSON ( Object or Array geoJSON)

###Parameters

• geoJSON : required : Either an Object representing a GeoJSON feature collection or an Array representing a list of GeoJSON features.

###Usage:

myRTree.geoJSON({
	"type":"FeatureCollection",
	"features":[
		{
			"type":"Feature",
			"geometry":{
				"type":"Point",
				"coordinates":[100,1]
			},
			"properties":{
				"prop0":"value0"
			}
		},
		{
			"type":"Feature",
			"geometry":{
				"type":"LineString",
				"coordinates":[
					[100,0],
					[101,1]
				]
			},
			"properties":{
				"prop0":"value0"
			}
		}
	]
});

##rTree.bbox:

• rTree.bbox ( Bounds area)

###Parameters

• area : required : Area to search, this can either be represented by a single parameter bounds array [[x1,y1],[x2,y2]], two parameters representing the southwest and northeast corners [x1,y1],[x2,y2], or 4 parameters of [x1,y1,x2,y2].

###Returns:

• An array of matched features.

###Usage:

• Search a 10x10 area that starts at position 10x10 (these are all equivalent):
• var myObjects1 = myRTree.bbox([[10,10],[20,20]]);
• var myObjects2 = myRTree.bbox([[10,10],[20,20]]);
• var myObjects3 = myRTree.bbox([10,10],[20,20]);
• var myObjects4 = myRTree.bbox([10,10],[20,20]);
• var myObjects5 = myRTree.bbox(10,10,20,20);
• var myObjects6 = myRTree.bbox(10,10,20,20);

##rTree.search

• RTree.search ( Rectangle³ area [, Boolean return node, Array return_array ])

###Parameters:

• area : required : An area to search within.
• return node : optional : Whether to return the entire node, mainly internal option.
• return array : optional : An existing array to add the results to, defaults to [], mainly internal option.

###Returns:

• An array of objects that overlap or touch area.

###Usage:

• Search a 10x10 area that starts at position 10x10:
• var myObjects = myRTree.search({x:10, y:10, w:10, h:10});

###Notes

¹ Default max node width is currently 6.

³ A Rectangle is any object with public x, y, w, h properties. The object itself is not saved or used directly but copies are made of its x, y, w, h properties.