| | Defines a non-persistent transformation in 3D space. <br>
This transformation is a general transformation.
It can be a Trsf from gp, an affinity, or you can define
your own transformation giving the matrix of transformation.
With a Gtrsf you can transform only a triplet of coordinates
XYZ. It is not possible to transform other geometric objects
because these transformations can change the nature of non-
elementary geometric objects.
The transformation GTrsf can be represented as follow :
V1 V2 V3 T XYZ XYZ
| a11 a12 a13 a14 | | x | | x'|
| a21 a22 a23 a24 | | y | | y'|
| a31 a32 a33 a34 | | z | = | z'|
| 0 0 0 1 | | 1 | | 1 |
where {V1, V2, V3} define the vectorial part of the
transformation and T defines the translation part of the
transformation.
Warning
A GTrsf transformation is only applicable to
coordinates. Be careful if you apply such a
transformation to all points of a geometric object, as
this can change the nature of the object and thus
render it incoherent!
Typically, a circle is transformed into an ellipse by an
affinity transformation. To avoid modifying the nature of
an object, use a gp_Trsf transformation instead, as
objects of this class respect the nature of geometric objects.
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1.8.5