A Collection is exactly what it sounds like: A collection of different Geometries.
These are stored in the local parameter *components* (which can
be passed as a parameter to the constructor).

As new geometries are added to the collection, they are NOT cloned. When removing geometries, they need to be specified by reference (ie you have to pass in the exact geometry to be removed).

The <getArea> and *getLength* functions here merely iterate through the components,
summing their respective areas and lengths.

Create a new instance with the *ZOO.Geometry.Collection* constructor.

Inherits from

NAME | DESCRIPTION |
---|---|

components |
{Array(ZOO.Geometry)} The component parts of this geometry |

componentTypes |
{Array(String)} An array of class names representing the types of components that the collection can include. |

NAME | DESCRIPTION |
---|---|

ZOO.Geometry.Collection |
Creates a Geometry Collection – a list of geoms. |

destroy |
Destroy this geometry. |

clone |
Clone this geometry. |

getComponentsString |
Get a string representing the components for this collection. |

calculateBounds |
Recalculate the bounds by iterating through the components and calling extendBounds() on each item. |

addComponent |
Add a new component (geometry) to the collection. |

removeComponents |
Remove components from this geometry. |

removeComponent |
Remove a component from this geometry. |

getLength |
Calculate the length of this geometry. |

getCentroid |
{ZOO.Geometry.Point} The centroid of the collection. |

getGeodesicLength |
Calculate the approximate length of the geometry were it projected onto the earth. |

move |
Moves a geometry by the given displacement along positive x and y axes. |

rotate |
Rotate a geometry around some origin. |

resize |
Resize a geometry relative to some origin. |

equals |
Determine whether another geometry is equivalent to this one. |

transform |
Reproject the components geometry from source to dest. |

intersects |
Determine if the input geometry intersects this one. |

getVertices |
Return a list of all points in this geometry. |

**Properties**

- components
- {Array(
*ZOO.Geometry*)} The component parts of this geometry

- componentTypes
`{Array(String)}`An array of class names representing the types of components that the collection can include. A null value means the component types are not restricted.

**Functions**

- ZOO.Geometry.Collection
Creates a Geometry Collection – a list of geoms.

*Parameters*`components`{Array(*ZOO.Geometry*)} Optional array of geometries

- destroy
destroy: function ()

Destroy this geometry.

- clone
clone: function()

Clone this geometry.

*Returns**{ZOO.Geometry.Collection}*An exact clone of this collection.

- getComponentsString
getComponentsString: function()

Get a string representing the components for this collection.

*Returns*`{String}`A string representation of the components of this geometry.

- calculateBounds
calculateBounds: function()

Recalculate the bounds by iterating through the components and calling extendBounds() on each item.

- addComponent
addComponent: function(component,index)

Add a new component (geometry) to the collection. If this.componentTypes is set, then the component class name must be in the componentTypes array. The bounds cache is reset.

*Parameters*`component`*{ZOO.Geometry}*A geometry to add`index {int}`Optional index into the array to insert the component*Returns*`{Boolean}`The component geometry was successfully added

- removeComponents
removeComponents: function(components)

Remove components from this geometry.

*Parameters*`components`{Array(*ZOO.Geometry*)} The components to be removed

- removeComponent
removeComponent: function(component)

Remove a component from this geometry.

*Parameters*`component`*{ZOO.Geometry}*

- getLength
getLength: function()

Calculate the length of this geometry

*Returns*`{Float}`The length of the geometry

- getCentroid
getCentroid: function()

*Returns**{ZOO.Geometry.Point}*The centroid of the collection

- getGeodesicLength
getGeodesicLength: function(projection)

Calculate the approximate length of the geometry were it projected onto the earth.

*Parameters*`projection`*{ZOO.Projection}*The spatial reference system for the geometry coordinates. If not provided, Geographic/WGS84 is assumed.*Returns*`{Float}`The appoximate geodesic length of the geometry in meters.

- move
move: function(x,y)

Moves a geometry by the given displacement along positive x and y axes. This modifies the position of the geometry and clears the cached bounds.

*Parameters*`x {Float}`Distance to move geometry in positive x direction.`y {Float}`Distance to move geometry in positive y direction.

- rotate
rotate: function(angle,origin)

Rotate a geometry around some origin

*Parameters*`angle {Float}`Rotation angle in degrees (measured counterclockwise from the positive x-axis)`origin`*{ZOO.Geometry.Point}*Center point for the rotation

- resize
resize: function(scale,origin,ratio)

Resize a geometry relative to some origin. Use this method to apply a uniform scaling to a geometry.

*Parameters*`scale {Float}`Factor by which to scale the geometry. A scale of 2 doubles the size of the geometry in each dimension (lines, for example, will be twice as long, and polygons will have four times the area).`origin`*{ZOO.Geometry.Point}*Point of origin for resizing`ratio {Float}`Optional x:y ratio for resizing. Default ratio is 1.*Returns**{ZOO.Geometry}*The current geometry.

- equals
equals: function(geometry)

Determine whether another geometry is equivalent to this one. Geometries are considered equivalent if all components have the same coordinates.

*Parameters*`geom`*{ZOO.Geometry}*The geometry to test.*Returns*`{Boolean}`The supplied geometry is equivalent to this geometry.

- transform
transform: function(source,dest)

Reproject the components geometry from source to dest.

*Parameters*`source`*{ZOO.Projection}*`dest`*{ZOO.Projection}**Returns*

- intersects
intersects: function(geometry)

Determine if the input geometry intersects this one.

*Parameters*`geometry`*{ZOO.Geometry}*Any type of geometry.*Returns*`{Boolean}`The input geometry intersects this one.

- getVertices
getVertices: function(nodes)

Return a list of all points in this geometry.

*Parameters*`nodes {Boolean}`For lines, only return vertices that are endpoints. If false, for lines, only vertices that are not endpoints will be returned. If not provided, all vertices will be returned.*Returns*`{Array}`A list of all vertices in the geometry.