CircleEvent

class foronoi.events.circle_event.CircleEvent(center: foronoi.graph.coordinate.Coordinate, radius: decimal.Decimal, arc_node: foronoi.nodes.leaf_node.LeafNode, point_triple=None, arc_triple=None)

A circle event.

Parameters

  • center (Coordinate) – The center coordinate of the circle (where the new vertex will appear)

  • radius (Decimal) – The radius of the circle

  • arc_node (LeafNode) – Pointer to the node in the beach line tree that holds the arc that will disappear

  • point_triple ((Point, Point, Point)) – The triple of points that caused the event

  • arc_triple ((Arc, Arc, Arc)) – The triple of arcs related to the points

static create_circle(a, b, c)

Create a circle from three coordinates.

Parameters
Returns

  • x (Decimal) – The x-coordinate of the center of the circle

  • y (Decimal) – The y-coordinate of the center of the circle

  • radius (Decimal) – The radius of the circle

static create_circle_event(left_node: foronoi.nodes.leaf_node.LeafNode, middle_node: foronoi.nodes.leaf_node.LeafNode, right_node: foronoi.nodes.leaf_node.LeafNode, sweep_line) → foronoi.events.circle_event.CircleEvent

Checks if the breakpoints converge, and inserts circle event if required.

Parameters

  • left_node (LeafNode) – The node that represents the arc on the left

  • middle_node (LeafNode) – The node that represents the arc in the middle

  • right_node (LeafNode) – The node that represents the arc on the right

  • sweep_line (Decimal) – The y-coordinate of the sweep line

Returns

circleEvent – The circle event or None if no circle event needs to be inserted

Return type

CircleEvent or None

remove()

Mark this circle event as a false alarm.

Returns

self

Return type

CircleEvent

property xd

The x-coordinate (in Decimal format) of the center of the circle, which functions as the secondary priority of this event.

Returns

x

Return type

Decimal

property yd

The y-coordinate (in Decimal format) of the bottom of the circle, which functions as the primary priority of this event.

Returns

y

Return type

Decimal