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LerpPoints


Header: FIL.h
Namespace: fil
Module: FoundationLite

Linearly interpolates between two points.

Syntax

C++
C#
 
void fil::LerpPoints
(
	const fil::Point2D& inPoint0,
	const fil::Point2D& inPoint1,
	float inLambda,
	fil::Point2D& outPoint
)

Parameters

Name Type Range Default Description
Input value inPoint0 const Point2D&
Input value inPoint1 const Point2D&
Input value inLambda float - - 0.5f Interpolation between the input points where 0.0 value is equal to inPoint0 and 1.0 to inPoint1
Output value outPoint Point2D&

In-place Processing

This function supports in-place data processing - you can pass the same reference to inPoint1 and outPoint

Read more about In-place Computation.

Examples

LerpPoints performed on red inPoint0 and blue inPoint1 with inLambda = 0,25. Green is the resulting outPoint.

LerpPoints performed on red inPoint0 and blue inPoint1 with inLambda = -1,0. Green is the resulting outPoint.

Remarks

Please note that:
  • interpolation begins at inPoint0,
  • for positive inLambda values interpolation is performed in the direction of inPoint1 while for negative - in the direction of a point which is the result of the following operation: (inPoint0 - inPoint1), in example a point acquired by mirroring inPoint1 by inPoint0.
Hence when inLambda = 0,0, outPoint is equal to inPoint0, while for inLambda = 1,0 it's the same as inPoint1 and for inLambda = -1,0 - as (inPoint0 - inPoint1). Other inLambda values interpolate between the input points and beyond.