VARKON Version 1.15 1997-12-29

cur_sil - Geometric procedure

Creates a curve


Description

Input data for the silhouette curve calculation is a surface and an eye point (at a finite distance from the surface) or a viewing direction (eye point at an infinite distance).

Syntax

cur_sil(id, ref, eye, type, branch:attributes);

REF	id;
REF	ref;
VECTOR	eye;
INT	type;
INT	branch;

Principal parameters

id	- Local identity
ref	- Surface
eye	- Eye point or viewing direction
type	- Type of silhouette curve
	Eq. 1: Perspective with eye point (at a finite distance)
	Eq. 2: Eye point at an infinite distance
	Eq. 3: Special (infinite distance) silhouette for a surface of type LFT_SUR
branch	- Requested branch of the silhouette curve
	(If 1000 is added will the graphical representation be the UV curve)

Optional parameters

None

Attributes

PEN	- Pen or colour number
LEVEL	- Level number
BLANK	- Visible (0) or invisible (1)
CFONT	- Solid (0), dashed (1), center line (2)
CDASHL	- Dash length
WIDTH	- Linewidth

Example

cur_sil( #3, #2, "U", vec(0.0, 1.3, 1.1), 2, 1);

Creates a silhouette curve #3 on surface #2. Eye point is at infinite distance and the viewing direction is vec(0.0, 1.3, 1.1). The first curve branch is requested.