ALKMaps.Handler.Polygon

Handler to draw a polygon on the map. Polygon is displayed on mouse down, moves on mouse move, and is finished on mouse up. Modified to use ALKPath handler.

Inherits from

Summary

ALKMaps.Handler.Polygon	Handler to draw a polygon on the map.
Properties
holeModifier	{String} Key modifier to trigger hole digitizing.
drawingHole	{Boolean} Currently drawing an interior ring.
polygon	{ALKMaps.Feature.Vector}
Constructor
ALKMaps.Handler.Polygon	Create a Polygon Handler.
Functions
createFeature	Add temporary geometries
addPoint	Add point to geometry.
getCurrentPointIndex	{Number} The index of the most recently drawn point.
enforceTopology	Simple topology enforcement for drawing interior rings.
finishGeometry	Finish the geometry and send it back to the control.
finalizeInteriorRing	Enforces that new ring has some area and doesn’t contain vertices of any other rings.
cancel	Finish the geometry and call the “cancel” callback.
restoreFeature	Move the feature from the sketch layer to the target layer.
destroyFeature	Destroy temporary geometries
drawFeature	Render geometries on the temporary layer.
getSketch	Return the sketch feature.
getGeometry	Return the sketch geometry.

Properties

holeModifier

{String} Key modifier to trigger hole digitizing. Acceptable values are “altKey”, “shiftKey”, or “ctrlKey”. If not set, no hole digitizing will take place. Default is null.

drawingHole

{Boolean} Currently drawing an interior ring.

polygon

{ALKMaps.Feature.Vector}

Constructor

ALKMaps.Handler.Polygon

Create a Polygon Handler.

Parameters

control	{ALKMaps.Control} The control that owns this handler
callbacks	{Object} An object with a properties whose values are functions. Various callbacks described below.
options	{Object} An optional object with properties to be set on the handler

Named callbacks

create	Called when a sketch is first created. Callback called with the creation point geometry and sketch feature.
modify	Called with each move of a vertex with the vertex (point) geometry and the sketch feature.
point	Called as each point is added. Receives the new point geometry.
done	Called when the point drawing is finished. The callback will receive a single argument, the polygon geometry.
cancel	Called when the handler is deactivated while drawing. The cancel callback will receive a geometry.

Functions

createFeature

createFeature: function( pixel )

Add temporary geometries

Parameters

pixel

{ALKMaps.Pixel} The initial pixel location for the new feature.

addPoint

addPoint: function( pixel )

Add point to geometry.

Parameters

pixel

{ALKMaps.Pixel} The pixel location for the new point.

getCurrentPointIndex

getCurrentPointIndex: function()

Returns

{Number} The index of the most recently drawn point.

enforceTopology

enforceTopology: function( event )

Simple topology enforcement for drawing interior rings. Ensures vertices of interior rings are contained by exterior ring. Other topology rules are enforced in finalizeInteriorRing to allow drawing of rings that intersect only during the sketch (e.g. a “C” shaped ring that nearly encloses another ring).

finishGeometry

finishGeometry: function()

Finish the geometry and send it back to the control.

finalizeInteriorRing

finalizeInteriorRing: function()

Enforces that new ring has some area and doesn’t contain vertices of any other rings.

cancel

cancel: function()

Finish the geometry and call the “cancel” callback.

restoreFeature

restoreFeature: function( cancel )

Move the feature from the sketch layer to the target layer.

Properties

cancel

{Boolean} Cancel drawing. If falsey, the “sketchcomplete” event will be fired.

destroyFeature

destroyFeature: function( force )

Destroy temporary geometries

Parameters

force

{Boolean} Destroy even if persist is true.

drawFeature

drawFeature: function()

Render geometries on the temporary layer.

getSketch

getSketch: function()

Return the sketch feature.

Returns

{ALKMaps.Feature.Vector}

getGeometry

getGeometry: function()

Return the sketch geometry. If <multi> is true, this will return a multi-part geometry.

Returns

{ALKMaps.Geometry.Polygon}