lin_tan1 - Geometric procedure

Creates a line


Description

Creates a line tangent to either an arc or a curve. Possible tangency alternatives are enumerated along the referenced entity and an alt parameter is supplied to select the right solution.

Syntax

lin_tan1(id, p, ref, alt:attributes);

REF	id;
VECTOR	p;
REF	ref;
INT	alt;

Principal parameters

id	- Local identity
p	- Start position
ref	- Identity of arc or curve
alt	- Requested position of tangency

Optional parameters

None.

Attributes

PEN	- Pen or colour number
LEVEL	- Level number
BLANK	- Visible(0) or invisible(1)
LFONT	- Solid(0), dashed(1) or centerline(2)
LDASHL	- Dashlength
WIDTH	- Linewidth

Example

lin_tan1(#6,vec(100,200),#3,2:BLANK=1,LEVEL=50);

Creates an invisible line on level 50 starting in X=100, Y=200 and ending in the second possible position of tangency with #3.

Comments

In a 3D module the resulting line is restricted to the XY-plane of the active coordinate system. If the start position p or the line ref is not in this plane they will be projected along the Z-axis onto the XY-plane before used to create the new line.