import ConnectivityConstraint from 'Artistoo/src/hamiltonian/ConnectivityConstraint.js'

public class | source

ConnectivityConstraint

Extends:

Constraint → HardConstraint → ConnectivityConstraint

this class is experimental.

This constraint enforces that cells stay 'connected' throughout any copy attempts. Copy attempts that break the cell into two parts are therefore forbidden. To speed things up, this constraint only checks if the borderpixels of the cells stay connected.

Constructor Summary

Public Constructor
public	constructor(conf: object) The constructor of the ConnectivityConstraint requires a conf object with one parameter.

Member Summary

Public Members
public set	CPM The set CPM method attaches the CPM to the constraint.
public	borderpixelsbycell: CellObject Object tracking the borderpixels of each cell.

Private Members
private	_neighbours: Uint16Array Private property used by updateBorderPixels to track borders.

Method Summary

Public Methods
public	checkConnected(tgt_i: IndexCoordinate, src_type: CellId, tgt_type: CellId): * This method checks if the connectivity still holds after pixel tgt_i is changed from tgt_type to src_type.
public	confChecker() This method checks that all required parameters are present in the object supplied to the constructor, and that they are of the right format.
public	connectedComponentsOf(pixelobject: object): object Get the connected components of a set of pixels.
public	connectedComponentsOfCellBorder(cellid: CellId): object Get the connected components of the borderpixels of the current cell.
public	fulfilled(src_i: IndexCoordinate, tgt_i: IndexCoordinate, src_type: CellId, tgt_type: CellId): boolean Method for hard constraints to compute whether the copy attempt fulfills the rule.
public	localConnected(tgt_i: IndexCoordinate, tgt_type: CellId): boolean To speed things up: first check if a pixel change disrupts the local connectivity in its direct neighborhood.
public	postSetpixListener(i: IndexCoordinate, t_old: CellId, t: CellId) The postSetpixListener of the ConnectivityConstraint updates the internally tracked borderpixels after every copy.
public	updateBorderPixels(i: IndexCoordinate, t_old: CellId, t_new: CellId) Update the borderpixels when pixel i changes from t_old into t_new.

Inherited Summary

From class Constraint
public get abstract	CONSTRAINT_TYPE This method is actually implemented in the subclass.
public set	CPM(C: CPM) This function attaches the relevant CPM to this constraint, so that information about this cpm can be requested from the constraint.
public get	parameters: object: * Get the parameters of this constraint from the conf object.
public	C: CPM CPM on which this constraint acts.
public	conf: object Configuration object for this constraint.
public abstract	cellParameter(param: string, cid: CellId): any Get a cellid or cellkind-specific parameter for a constraint.
public abstract	confChecker() The optional confChecker method should verify that all the required conf parameters are actually present in the conf object and have the right format.
public	paramOfCell(param: string, cid: CellId): any Get a cellId specific parameter, only used if CPMEvol is used: looks whether the requested parameter is overwritten in an @object Cell and otherwise returns @function paramOfKind
public	paramOfKind(param: string, cid: CellId): any Returns a cellKind specfic variable: Assumes that the parameter is indexable by cellkind.

From class HardConstraint
public get	CONSTRAINT_TYPE: string: string Let the CPM know that this is a soft constraint, so return 'soft'.
public abstract	fulfilled(src_i: IndexCoordinate, tgt_i: IndexCoordinate, src_type: CellId, tgt_type: CellId): boolean Hard constraints must have a 'fulfilled' method to compute whether the copy attempt fulfills the rule.

Public Constructors

public constructor(conf: object) source

The constructor of the ConnectivityConstraint requires a conf object with one parameter.

Override:

Constraint#constructor

Params:

Name	Type	Attribute	Description
conf	object		parameter object for this constraint.
conf.CONNECTED	PerKindBoolean		should the cellkind be connected or not?

Public Members

public set CPM source

The set CPM method attaches the CPM to the constraint.

Override:

Constraint#CPM

public borderpixelsbycell: CellObject source

Object tracking the borderpixels of each cell. This is kept up to date after every copy attempt.

Private Members

private _neighbours: Uint16Array source

Private property used by updateBorderPixels to track borders.

Public Methods

public checkConnected(tgt_i: IndexCoordinate, src_type: CellId, tgt_type: CellId): * source

This method checks if the connectivity still holds after pixel tgt_i is changed from tgt_type to src_type.

Params:

Name	Type	Attribute	Description
tgt_i	IndexCoordinate		the pixel to change
src_type	CellId		the new cell for this pixel.
tgt_type	CellId		the cell the pixel belonged to previously.

Return:

public confChecker() source

This method checks that all required parameters are present in the object supplied to the constructor, and that they are of the right format. It throws an error when this is not the case.

Override:

Constraint#confChecker

public connectedComponentsOf(pixelobject: object): object source

Get the connected components of a set of pixels.

Params:

Name	Type	Attribute	Description
pixelobject	object		an object with as keys the IndexCoordinates of the pixels to check.

Return:

object

an array with an element for every connected component, which is in turn an array of the ArrayCoordinates of the pixels belonging to that component.

public connectedComponentsOfCellBorder(cellid: CellId): object source

Get the connected components of the borderpixels of the current cell.

Params:

Name	Type	Attribute	Description
cellid	CellId		cell to check the connected components of.

Return:

object

an array with an element for every connected component, which is in turn an array of the ArrayCoordinates of the pixels belonging to that component.

public fulfilled(src_i: IndexCoordinate, tgt_i: IndexCoordinate, src_type: CellId, tgt_type: CellId): boolean source

Method for hard constraints to compute whether the copy attempt fulfills the rule.

Override:

HardConstraint#fulfilled

Params:

Name	Type	Attribute	Description
src_i	IndexCoordinate		coordinate of the source pixel that tries to copy.
tgt_i	IndexCoordinate		coordinate of the target pixel the source is trying to copy into.
src_type	CellId		cellid of the source pixel.
tgt_type	CellId		cellid of the target pixel.

Return:

boolean

whether the copy attempt satisfies the constraint.

public localConnected(tgt_i: IndexCoordinate, tgt_type: CellId): boolean source

To speed things up: first check if a pixel change disrupts the local connectivity in its direct neighborhood. If local connectivity is not disrupted, we don't have to check global connectivity at all. This currently only works in 2D, so it returns false for 3D (ensuring that connectivity is checked globally).

Params:

Name	Type	Attribute	Description
tgt_i	IndexCoordinate		the pixel to change
tgt_type	CellId		the cell the pixel belonged to before the copy attempt.

Return:

boolean

does the local neighborhood remain connected if this pixel changes?

public postSetpixListener(i: IndexCoordinate, t_old: CellId, t: CellId) source

The postSetpixListener of the ConnectivityConstraint updates the internally tracked borderpixels after every copy.

Params:

Name	Type	Attribute	Description
i	IndexCoordinate		the pixel to change
t_old	CellId		the cell the pixel belonged to previously
t	CellId		the cell the pixel belongs to now.

public updateBorderPixels(i: IndexCoordinate, t_old: CellId, t_new: CellId) source

Update the borderpixels when pixel i changes from t_old into t_new.

Params:

Name	Type	Attribute	Description
i	IndexCoordinate		the pixel to change
t_old	CellId		the cell the pixel belonged to previously
t_new	CellId		the cell the pixel belongs to now.