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PointAlongArc

Header:	FIL.h
Namespace:	fil
Module:	FoundationLite

Transforms a point to a coordinate system in which the 'axis' arc is vertical or horizontal.

Applications: Usually used to revert an ImageAlongArc transformation.

Syntax

void fil::PointAlongArc
(
	const fil::Point2D& inPoint,
	const fil::Arc2D& inAxis,
	fil::Axis::Type inAxisType,
	float inAxisCoordinate,
	bool inInverse,
	fil::Point2D& outPoint
)

Parameters

Name	Type	Default	Description
inPoint	const Point2D&		Input point
inAxis	const Arc2D&		Input axis arc
inAxisType	Axis::Type	Y	Type of axis the input axis arc is parallel to
inAxisCoordinate	float	0.0f	Coordinate of the axis arc
inInverse	bool	True	Switches to the inverse operation
outPoint	Point2D&		Transformed point

Description

This operation transforms a point - inPoint - between two coordinate systems: the one linked with 'axis' arc inAxis and the original one. Direction of this conversion is based on inInverse value:

if it is true, inPoint is converted to original coordinate system
if it is false, inPoint is converted from original coordinate system

Coordinate system linked with inAxis is some transformation of the original one, satisfying these conditions:

'axis' arc is represented as a straight line
'axis' arc is horizontal if inAxisType is set to X or vertical if inAxisType is set to Y
if inAxisType is set to X, the Y coordinate of 'axis' arc is equal to inAxisCoordinate. If inAxisType is set to Y, the X coordinate of 'axis' arc is equal to inAxisCoordinate

Hints

If this filter is used to reverse ImageAlongArc transformation you should set inAxis and inAxisType to the same values as corresponding ones in ImageAlongArc. inAxisCoordinate should be set to a half of ImageAlongArc.inScanWidth.

Examples