API reference - Class EdgeNeighborhoodVisitor

_const_cast

Signature: [const] EdgeNeighborhoodVisitor ptr _const_cast

Description: Returns a non-const reference to self.

Basically, this method allows turning a const object reference to a non-const one. This method is provided as last resort to remove the constness from an object. Usually there is a good reason for a const object reference, so using this method may have undesired side effects.

This method has been introduced in version 0.29.6.

_create

Signature: void _create

Description: Ensures the C++ object is created

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

_destroy

Signature: void _destroy

Description: Explicitly destroys the object

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

_destroyed?

Signature: [const] bool _destroyed?

Description: Returns a value indicating whether the object was already destroyed

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

_is_const_object?

Signature: [const] bool _is_const_object?

Description: Returns a value indicating whether the reference is a const reference

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

_manage

Signature: void _manage

Description: Marks the object as managed by the script side.

After calling this method on an object, the script side will be responsible for the management of the object. This method may be called if an object is returned from a C++ function and the object is known not to be owned by any C++ instance. If necessary, the script side may delete the object if the script's reference is no longer required.

Usually it's not required to call this method. It has been introduced in version 0.24.

_unmanage

Signature: void _unmanage

Description: Marks the object as no longer owned by the script side.

Calling this method will make this object no longer owned by the script's memory management. Instead, the object must be managed in some other way. Usually this method may be called if it is known that some C++ object holds and manages this object. Technically speaking, this method will turn the script's reference into a weak reference. After the script engine decides to delete the reference, the object itself will still exist. If the object is not managed otherwise, memory leaks will occur.

Usually it's not required to call this method. It has been introduced in version 0.24.

assign

Signature: void assign (const EdgeNeighborhoodVisitorBase other)

Description: Assigns another object to self

begin_polygon

Signature: [virtual] void begin_polygon (const Layout ptr layout, const Cell ptr cell, const Polygon polygon)

Description: Is called for each new polygon

This event announces a new primary polygon. After this event, the edges of the polygon are reported via on_edge, followed by a call of end_polygon.

Note, that the polygon object is a temporary reference to a C++ object and it is only valid during the execution of this callback. If you like to keep the polygon object, create a copy of it using the 'dup' method.

create

Signature: void create

Description: Ensures the C++ object is created

Use of this method is deprecated. Use _create instead

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

destroy

Signature: void destroy

Description: Explicitly destroys the object

Use of this method is deprecated. Use _destroy instead

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

destroyed?

Signature: [const] bool destroyed?

Description: Returns a value indicating whether the object was already destroyed

Use of this method is deprecated. Use _destroyed? instead

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

dup

Signature: [const] new EdgeNeighborhoodVisitorBase ptr dup

Description: Creates a copy of self

Python specific notes:
This method also implements '__copy__' and '__deepcopy__'.

end_polygon

Signature: [virtual] void end_polygon

Description: Is called after the polygon

See begin_polygon for a description of this protocol.

is_const_object?

Signature: [const] bool is_const_object?

Description: Returns a value indicating whether the reference is a const reference

Use of this method is deprecated. Use _is_const_object? instead

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

new

Signature: [static] new EdgeNeighborhoodVisitorBase ptr new

Description: Creates a new object of this class

Python specific notes:
This method is the default initializer of the object.

on_edge

Signature: [virtual] void on_edge (const Layout ptr layout, const Cell ptr cell, const Edge edge, variant neighborhood)

Description: Is called for each edge with the edge neighbors

This method is called for every edge on the input region. It delivers the edge and the edge neighborhood. The edge neighborhood is classified in intervals along the edge. The intervals are given by a range of positions along the edge - 0.0 being the beginning of the edge and positive values towards the end of the edge. For 'bext' and 'eext' larger than zero (see EdgeNeighborhoodCompoundOperationNode), the position can be negative or larger than the edge length.

The structure of the neighbors is:

[
  [ [ from, to ], { input_index => polygons } ]
]

'from' and 'to' are the positions of the interval, 'input_index' is the index of the input the neighbors are on (see 'children' argument of EdgeNeighborhoodCompoundOperationNode constructor), 'prop_id' is the properties ID of the neighbors and 'polygons' is a list of polygons describing the neighborhood. The polygons are projected on the edge - i.e. they are in a coordinate system where the edge is horizonal and goes from (0,0) to (length,0).

The polygons are boxes for manhattan input and trapezoids in the general case.

output

(1) Signature: void output (const Polygon polygon)

Description: Outputs a polygon

Use this method from one of the callbacks (on_edge, begin_polygon, end_polygon) to deliver a polygon. Note that you have to configure the result type as 'Region' on construction of the visitor before being able to do so.

'output' expects an object in original space - i.e. of the input edge. to_original_trans gives you a suitable transformation to bring objects from 'edge is horizontal' space into the original space.

(2) Signature: void output (const Edge edge)

Description: Outputs an edge

Use this method from one of the callbacks (on_edge, begin_polygon, end_polygon) to deliver a polygon. Note that you have to configure the result type as 'Edges' on construction of the visitor before being able to do so. 'output' expects an object in original space - i.e. of the input edge. to_original_trans gives you a suitable transformation to bring objects from 'edge is horizontal' space into the original space.

(3) Signature: void output (const EdgePair edge_pair)

Description: Outputs an edge pair

Use this method from one of the callbacks (on_edge, begin_polygon, end_polygon) to deliver a polygon. Note that you have to configure the result type as 'EdgePairs' on construction of the visitor before being able to do so. 'output' expects an object in original space - i.e. of the input edge. to_original_trans gives you a suitable transformation to bring objects from 'edge is horizontal' space into the original space.

result_type

Signature: [const] CompoundRegionOperationNode::ResultType result_type

Description: Gets the result type

Python specific notes:
The object exposes a readable attribute 'result_type'. This is the getter.

result_type=

Signature: void result_type= (CompoundRegionOperationNode::ResultType result_type)

Description: Configures the result type

Use this method to indicate what type of result you want to deliver. You can use the corresponding 'output' method then to deliver result shapes from one the callbacks (on_edge, begin_polygon, end_polygon). Set this attribute when you create the visitor object. This attribute does not need to be set if no output is indended to be delivered.

Python specific notes:
The object exposes a writable attribute 'result_type'. This is the setter.

to_edge_local_trans

Signature: [static] IMatrix3d to_edge_local_trans (const Edge edge)

Description: For a given edge, computes the transformation that brings objects from original space to the edge-local space where the edge is horizontal.

Technically, this transformation is the inverse of to_original_trans.

to_original_trans

Signature: [static] IMatrix3d to_original_trans (const Edge edge)

Description: For a given edge, computes the transformation that brings objects from the normalized space (edge is horizontal) to the original space of the edge.

Use this method to compute the objects suitable for 'output', after you derived them in edge-local space.