openfoam/src/fileFormats/fire

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                              AVL/FIRE fpma/fpmb
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fpma/fpmb are polyhedral formats (ASCII and BINARY).
The fpmaz/fpmbz are the same, but in compressed format.

The fpma/fpmb format can exported directly from within the FIRE GUI.
However, it is not recommended to import them directly.
Instead use the utility fire_wm_convert_file, fire_wm_convert_mesh
(or equivalents)
are used to rewrite the fpma/fpmb into the internal FIRE format.


~~~~~~
FORMAT
~~~~~~

NUMBER_OF_VERTICES
x0 y0 z0 x1 y1 z1 ... xN-1 yN-1 zN-1


NUMBER_OF_FACES
face-stream0
...
face-streamN-1


NUMBER_OF_CELLS
cell-face-stream0
..
cell-face-streamN-1


NUMBER_OF_SELECTIONS
selectionName[0]
selectionType[0] (2 = cells, 3 = faces)
numberOfIDs
id0 .. indN-1
<blank-line>



The face-stream:
    nvert vert0 .. vertN

The cell-face-stream:
    nface faceId0 .. faceIdN


CAUTION:
    The FIRE faces have inward-facing normals.
    The OPENFOAM faces have outward-facing normals!


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                 AVL/FIRE flma
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The AVL/FIRE flma format is very simple, but can only be used for 1D/2D shapes
and for 3D primitive shapes.

it is fairly easy to write and to parse.
For 3D polyhedra, the cell-types are non-obvious and not easily determined
- the fpma/fpmb format is preferred for that.


~~~~~~
FORMAT
~~~~~~
NUMBER_OF_VERTICES
x0 y0 z0 x1 y1 z1 ... xN-1 yN-1 zN-1

NUMBER_OF_CELLS
nv[0]
verts[0]
nv[N-1]
...
verts[N-1]
<blank-line>
NUMBER_OF_CELLS
type0 type1 ... type2
<blank-line>
NUMBER_OF_SELECTIONS
selectionName[0]
selectionType[0] (2 = cells, 3 = faces)
numberOfIDs
id0 .. indN-1
<blank-line>
...
selectionName[N-1]
selectionType[N-1] (2 = cells, 3 = faces)
numberOfIDs
id0 .. indN-1
<blank-line>


-- NOTES (flma) --
# vertex/cells are zero-based

    cell-types:
      1 = line
      2 = tri
      3 = quad
      4 = tet
      5 = hex
      6 = pyr
      8 = prism

    +---------------+---------------+
    |  shape        |  face-order   |
    +---------------+---------------+
    +  Tet(FIRE)    |  0 1 2 3      |
    +  Tet(FOAM)    |  3 2 0 1      |
    +---------------+---------------+
    +  Hex(FIRE)    |  0 1 2 3 4 5  |
    +  Hex(FOAM)    |  4 5 0 1 2 3  |
    +---------------+---------------+
    +  Pyr(FIRE)    |  0 1 2 3 4    |
    +  Pyr(FOAM)    |  0 4 3 2 1    |
    +---------------+---------------+
    +  Prism(FIRE)  |  0 1 2 3 4    |
    +  Prism(FOAM)  |  0 1 4 3 2    |
    +---------------+---------------+