Polygon2D

Class full path: NemAll_Python_Geometry.Polygon2D

Bases: PolyPoints2D

Representation class for 2D Polygon

For constructing a polygon from a bunch of points, the following rules must be fulfilled: This class does not 'auto-close' polygons. A quadratic shape with '4' edges has to be defined by passing 5 points to a constructor. For such an object, the Count() method will return '5' accordingly. The orientation of points must be monotonous. It can be either clockwise or counter-clockwise. The polygon must not self-intersect itself. You can create instances of polygons that self-intersects or have alternating orientation, but in those cases some methods will report errors, throw or return wrong calculation results.

Each polygon is compound from one or more components. Component is a loop. Component represent solid element or hole element, it depend on orientation of loop (counter-clockwise is solid element, clockwise is hole). When polygon is created from more compounds, then each compound must be closed (first and last point are equal) and first and last point of hole polygon are equal too.

For better polygon creation you can use Builder::Polygon2DBuilder class.

Functions

CreateRectangle(leftBottom, rightTop) staticmethod

Create a rectangle

Parameters:

Name	Type	Description	Default
leftBottom	Point2D	Left bottom point	required
rightTop	Point2D	Right top point	required

Returns:

Type	Description
Polygon2D	Polygon of the rectangle

GetSegments()

Get polygon segments

Returns:

Type	Description
eGeometryErrorCode	error code
List[Line2D]	vector of polygon segments

IsValid()

Check if the polygon is valid ( has at least 3 points )

For additional point validation use Validate.

Returns:

Type	Description
bool	true if is valid

Normalize(normalizeType=DEFAULT_NORM_TYPE, extra_smooth=False)

Normalize Polygon2D.

Using huge old algorithm, adding points at line crossings, reorganizing the lines, correcting gaps, ... This method is checked and throwing Exception when error occurs.

Parameters:

Name	Type	Description	Default
normalizeType	ePolygonNormalizeType	type of Polygon2D normalization	DEFAULT_NORM_TYPE
extra_smooth	bool	Including extra smooth: true/false	False

NormalizeNoThrow(normalizeType=DEFAULT_NORM_TYPE, extra_smooth=False)

Normalize Polygon2D.

Same as Normalize, but method doesn't throw exception, just return error code

Parameters:

Name	Type	Description	Default
normalizeType	ePolygonNormalizeType	type of Polygon2D normalization	DEFAULT_NORM_TYPE
extra_smooth	bool	Including extra smooth: true/false	False

Returns:

Type	Description
object	Error code (eOK, eAllocError, eStructuralError)

Reverse()

Reverse the point order in polygon, separatelly for every subpolygon

__eq__(polygon2)

Equal operator

Parameters:

Name	Type	Description	Default
polygon2	Polygon2D	Second polygon	required

Returns:

Type	Description
bool	Polyline3D are equal

__iadd__(point)

Addition assignment operator

Parameters:

Name	Type	Description	Default
point	Point2D	Point which will be added	required

Returns:

Type	Description
Polygon2D	Reference to polygon

__init__ overload

__init__()

initialize

__init__(pntList)

Constructor with an initializer list

Parameters:

Name	Type	Description	Default
pntList	List	Point list	required

__init__(polygon)

Copy constructor.

Parameters:

Name	Type	Description	Default
polygon	Polygon2D	Polygon which will be copied	required

__ne__(polygon2)

Not equal operator

Parameters:

Name	Type	Description	Default
polygon2	Polygon2D	Second polygon	required

Returns:

Type	Description
bool	Polyline3D are equal

__repr__()

Convert to string