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LerpVectors_Radial

Header:	FIL.h
Namespace:	fil
Module:	FoundationLite

Linearly interpolates between two radial vectors.

Syntax

void fil::LerpVectors_Radial
(
	const fil::Vector2D& inVector0,
	const fil::Vector2D& inVector1,
	ftl::Optional<fil::RotationDirection::Type> inRotationDirection,
	const float inLambda,
	fil::Vector2D& outVector
)

Parameters

Name	Type	Range	Default	Description
inVector0	const Vector2D&
inVector1	const Vector2D&
inRotationDirection	Optional<RotationDirection::Type>		NIL	Clockwise, counter-clockwise or auto
inLambda	const float	- -	0.5f	Interpolation between the input vectors where 0.0 value is equal to inVector0 and 1.0 to inVector1
outVector	Vector2D&

Description

Note that because of inaccuracies of floating-point arithmetic, some geometric operations (including this one) may lead to unpredictable results for degenerated cases. In this filter such a case occurs when a zero vector is given on input.

Examples

LerpVectors performed on red inVector0 = (150, 150) and blue inVector1 = (-50, 50) with inLambda = 0,25 and inRotationDirection = Clockwise. Green is the resulting outVector.

LerpVectors performed on red inVector0 = (50, 50) and blue inVector1 = (-25, 25) with inLambda = -1,0 and inRotationDirection = Clockwise. Green is the resulting outVector.

Remarks

Please note that:

interpolation begins at inVector0,
for positive inLambda values interpolation is performed in the direction of inVector1 while for negative - in the direction of a vector acquired by mirroring inVector1 by a line determined by inVector0 and its length properly adjusted.

Hence when inLambda = 0,0, outVector is equal to inVector0, while for inLambda = 1,0 it's the same as inVector1 and for inLambda = -1,0 - as the previously described vector. Other inLambda values interpolate between the input vectors and beyond.