FC_CircleThroughThreePoints3D

FC_CircleThroughThreePoints3D - General Information

Overview

Type:	Function
Available as of:	V1.0.3.0
Versions:	Current version

Task

Calculates a circle in the 3-dimensional space which passes through three specified points.

Description

Three points which must not be located on a straight line are specified in the 3-dimensional space. This function calculates the center, the radius and the normal vector of the plane in which the circle lies which passes through these three points.

Interface

Input	Data type	Description
i_stPoint1	ST_Vector3D	Point 1 which the circle is to pass through
i_stPoint2	ST_Vector3D	Point 2 which the circle is to pass through
i_stPoint3	ST_Vector3D	Point 3 which the circle is to pass through

Output	Data type	Description
q_etDiag	GD.ET_Diag	General library-independent statement on the diagnostic. A value not equal to ET_Diag.Ok corresponds to an diagnostic message.
q_etDiagExt	ET_DiagExt	POU-specific output on the diagnostic. q_etDiag = ET_Diag.Ok -> Status message q_etDiag <> ET_Diag.Ok -> Diagnostic message

Output

Data type

Description

q_etDiag

GD.ET_Diag

General library-independent statement on the diagnostic.

A value not equal to ET_Diag.Ok corresponds to an diagnostic message.

q_etDiagExt

ET_DiagExt

POU-specific output on the diagnostic.

q_etDiag = ET_Diag.Ok -> Status message

q_etDiag <> ET_Diag.Ok -> Diagnostic message

Return Value

Data type	Description
ST_Circle3D	Calculated circle which passes through the three specified points.

Diagnostic Messages

q_etDiag	q_etDiagExt	Enumeration value	Description
OK	Ok	0	Ok
InputParameterInvalid	PointsCollinear	20	The points are located on a straight line.

Enumeration name:	Ok
Enumeration value:	0
Description:	Ok

The circle has been calculated successfully.

PointsCollinear

Enumeration name:	PointsCollinear
Enumeration value:	20
Description:	The points are located on a straight line.

Issue	Cause	Solution
-	The three points i_stPoint1, i_stPoint2 and i_stPoint3 are located on a straight line.	The three points i_stPoint1, i_stPoint2 and i_stPoint3 must not be located on a straight line.