Polygon class

An arbitrary polygon with 3 or more vertices.

The vertices of the polygon are in the counter-clockwise order, so that the polygon's interior is in your left-hand side as you traverse the polygon's vertices.

A polygon can be either convex or not, the containsPoint method will work in both cases, however, the method used with convex polygon is faster.

Inheritance

• Object
• Shape
• Polygon

Constructors

Polygon(List<Vector2> _vertices, {bool? convex})

Constructs the polygon from the given list of vertices.

Properties

aabb → Aabb2

The axis-aligned bounding box of the shape.

no setter, override

center → Vector2

The central point of the shape.

no setter, override

edges → List<Vector2>

The edges (sides) of the polygon.

no setter

hashCode → int

The hash code for this object.

no setter, inherited

isClosed → bool

True if the shape is "closed", in the sense that it has an interior. For example, a closed shape can be filled with a paint.

no setter, inherited

isConvex → bool

True if the shape is convex, i.e. a line segment connecting any two points of the shape would lie completely within the shape.

no setter, override

perimeter → double

The length of the shape's boundary. For some more complicated shapes this can be computed approximately.

no setter, override

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

vertices → List<Vector2>

The vertices (corners) of the polygon.

no setter

Methods

asPath() → Path

Converts the shape to a Path object, suitable for rendering on a canvas. If a particular geometric primitive cannot be represented as a Path faithfully, an approximate path can be returned.

override

containsPoint(Vector2 point) → bool

Returns true if the given point is inside the shape or on the boundary.

override

move(Vector2 offset) → void

Translates the shape by the specified offset vector, in-place.

override

nearestPoint(Vector2 point) → Vector2

Returns a point on the shape's boundary which is closest to the given point.

override

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

project(Transform2D transform, [Shape? target]) → Shape

Returns the result of applying an affine transformation to the shape.

override

randomPoint({Random? random, bool within = true}) → Vector2

Returns a random point within the shape if within is true (default) and otherwise a point along the edges of the shape. Do note that within=true also includes the edges.

override

support(Vector2 direction) → Vector2

Finds the intersection of this shape with another one, if it exists. Returns a point on the boundary that is furthest in the given direction.

override

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

randomPointAlongEdges(List<Vector2> vertices, {Random? random}) → Vector2

Returns a random point on the vertices.