norm - Function

Geometrical function


Description

Returns the (normalised) normal vector of a curve, surface, b_plane or coordiante system. If used on a coordinate system, the direction of the Z-axis is returned.

Syntax

norm(ref)

REF

ref;

This syntax is used for b_planes and coordinate systems.

norm(ref, t)

REF	ref;
FLOAT	t;

This syntax is used for curves.

norm(ref, uv)

REF	ref;
VECTOR	uv;

This syntax is used for surfaces. X- and Y-components of uv are used to hold the U- and V-values. The Z-component of uv is not used.

Principal parameters

ref	- ID of entity.

Optional parameters

t	- Parameter value for curve, default = 0
uv	- UV-value for surface. uv.x = U-value and uv.y = V-value

Return value

A VECTOR value equal to the normalised normal in the position specified.

Examples

n:=norm(#10);

The normal of a b_plane or coordinate system.

n:=norm(#5,0.5);

The normal vector of a position equal to t = 0.5 on a curve.


n:=norm(#5,vec(1.5,0.8));

The normal vector of a position equal to U=1.5 and V=0.8 on a surface.