IndexedXYCollection Class

abstract base class for access to XY data with indexed reference.

  • This allows algorithms to work with Point2d[] or GrowableXY.
    • GrowableXYArray implements these for its data.
    • Point2dArrayCarrier carries a (reference to) a Point2d[] and implements the methods with calls on that array reference.
  • In addition to "point by point" accessors, other abstract members compute commonly useful vector data "between points".
  • Methods that create vectors among multiple indices allow callers to avoid creating temporaries.

Extended by

Methods

Name Description
constructor(): IndexedXYCollection    
crossProductIndexIndexIndex(origin: number, indexA: number, indexB: number): undefined | number Abstract Return the cross product of vectors from origin point at indexA to target points at indexB and indexC  
crossProductXAndYIndexIndex(origin: Readonly<WritableXAndY>, indexA: number, indexB: number): undefined | number Abstract Return the cross product of vectors from origin to points at indexA and indexB  
getPoint2dAtCheckedPointIndex(index: number, result?: Point2d): undefined | Point2d Abstract Get from index as a Point2d  
getVector2dAtCheckedVectorIndex(index: number, result?: Vector2d): undefined | Vector2d Abstract Get from index as a Vector2d  
getXAtUncheckedPointIndex(pointIndex: number): number access x of indexed point  
getYAtUncheckedPointIndex(pointIndex: number): number access y of indexed point  
linearCombination(scales: number[], result?: Point2d | Vector2d): XY Compute the linear combination s of the indexed p_i and given scales s_i.  
vectorIndexIndex(indexA: number, indexB: number, result?: Vector2d): undefined | Vector2d Abstract Return a vector from the point at indexA to the point at indexB  
vectorXAndYIndex(origin: Readonly<WritableXAndY>, indexB: number, result?: Vector2d): undefined | Vector2d Abstract Return a vector from given origin to the point at indexB  

Properties

Name Type Description
length Accessor AbstractReadOnly number read-only property for number of XY in the collection.  

Defined in

Last Updated: 20 June, 2023