{ brep
model filename;
}
filename - name of the file, but in the same directory of the
scene.
brep object are described in brp file format.
{ pbrep
vertices
3
0 0 0
1 0 0
1 1 0
0 1 0
faces
1
{ 1 { 4 0 1 2 3 } }
}
This is a simple object. It is a square in the plane x-y with edge of 1.
Remember this is an open brep, you cannot assume it will be a transparent object.
There are definite four vertices, which we call A for (0,0,0) , B for ( 1,0,0) , C for (1,1,0) , D for (0,1,0) . It is definite one face with one contour. A face can have more than a contour; in this case the first contour is the external contour, while the others are holes in the face.
Every face has a normal versor, which describes the external side of a face. We can tell this to the program with the order we put the vertices in the contour description:
x exit
. enter
ABCD anticlockwise
ADCB clockwise
If you have a hole, the order of the hole contour must be opposite to the external.
defbrep_name
name of the file .brp which describes the geometric model of the object.
The file .brp will have name defbrep_name + ".brp" and will be in the directory
where are all the models.
defbrep_costr
value for the hierarchy of the object. If the value is equal to zero,
no hierarchy will be used. Se the value is different from zero and a previus
hierarchy of the object already exist, this will be used ( also if it has
been created with a different value). If the hierarchy doesn' t exist,
the program will create a new with compactness value equal to the value.
File .brp
Definition of a geometric model of type Boundary Representation.
A face is defined by some contours. The first contour is the extern contour, which must be always included; the other contours describe the holes in the face.
A contour of a face is defined by the values of vertex indexes which limit it.
You must verificate the condition that all vertices of all contours in a face are complanar.