## Concept of positioning

We call positioning of a face on a plan or on a cylinder the operation that consists in projecting the face on a reference plan or cylinder (defined by the user).

The corresponding command is Locate faces .

## Positioning of faces

Different possibilities of faces positioning proposed to the user are presented in the table below.

Location The face is projected on …
on a plane

a plane defined by its equation:

Ax+By+Cz+D=0

(the A, B, C and D coefficients are defined by the user)

a plane defined by:

a standard plane, an axis and a rotation angle

on a cylinder

a cylinder defined by:

an axis, a center and a radius

The planes defined by a standard plane, an axis and an angle of rotation are the following planes:

• Plane OXY / Axis X and angle θ x: plane obtained by rotation of plane OXY around the axis X of an angle θ x
• Plane OYZ / Axis Y and angle θ y: plane obtained by rotation of plane OYZ around the axis Y of an angle θ y
• Plane OZX / Axis Z and angle θ z: plane obtained by rotation of plane OZX around the axis X of an angle θ z

Example : The figure near represents a plane P obtained by rotation of plane OXY about the axis X of an angle θ x.