VARKON Version 1.15 1997-10-24

tform_rotp - Geometric procedure

Creates a transformation


Description

Creates a rotational transformation with optional scaling. This rotation is restricted to the XY-plane of the active coordinate system with a specified position as center.

Syntax

tform_rotp(id, p, rot, sx, sy, sz:attributes);

REF	id;
VECTOR	p;
FLOAT	rot;
FLOAT	sx;
FLOAT	sy;
FLOAT	sz;

Principal parameters

id	- Local identity
p	- Center of rotation and origin for optional scaling
rot	- Counterclockwise angle of rotation

Optional parameters

sx	- Scalefactor in X-direction, default = 1
sy	- Scalefactor in Y-direction, default = sx
sz	- Scalefactor in Z-direction, default = sy

Attributes

PEN	- Pen or colour number
LEVEL	- Level number
BLANK	- Visible(0) or invisible(1)

Example

tform_rotp(#1,vec(100,100),45);

An anticlockwise rotation of 45 degrees in the XY-plane with X=Y=100 as centre.

tform_rotp(#1,vec(100,100),-20,2.5);

A clockwise rotation of 20 degrees around X=Y=100 and simultaneous scaling in X and Y and Z with a factor of 2.5.

Comments

In a 2D module scaling in the Z-direction has no meaning.