brep object are described in brp file format.
The description of a simple file .brp:
{ 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.
5.5.2.4
Blob use only external model. The blob models are stored in .blb format, the same that the program Winblob. You can find it at:
ftp://ftp.povray.org/pub/povray/utilities/general/winblobs.zip
5.5.2.5.3