DIRSIG renders scenes consisting of 3D facetized objects. The creation of these scenes using AutoCAD and the AutoLISP support routines are not discussed in this manual. To summarize the process, the AutoLISP routines include a command to output the current drawing to an ASCII file that contains the geometry and attributes of the objects. This custom output file is created by the dirsigdump command, and hence the generated output file is usually referred to as a ``dump'' file. This file is then processed by a formatting program to create the Geometric Database (GDB) file.
The .dump file forms a hierarchical structure of objects, parts and facets. The importance of the facet hierarchy no longer exists as of Release 3.1, however, the file format must still be observed. Many of the facet attributes are no longer support on a per-facet basis and have been shifted to per-material attributes (these attributes are marked as [unused]). The ``dump'' file is very handy, because objects can be easily relocated or rotated by simply changing the insert point or rotation angle for the given object.
The next page contains a summary of the ``dump'' file. The vertex section of the facet entry always contains 4 vertices. If the facet has only three vertices, one of the vertex coordinates will be repeated.
Table 34-1. DUMP Sample File
| OBJECT | KEYWORD: OBJECT |
| TRUCK_OBJ | Name of object |
| (0.0 0.0 0.0) | X, Y, Z insertion point for this object |
| 1.0 | X axis scale factor for this object |
| 1.0 | Y axis scale factor for this object |
| 1.0 | Z axis scale factor for this object |
| 0.0 | X/Y plane rotation angle (radians) for this object |
| PART | KEYWORD: PART |
| TRUCK_BACK1_ATTS | Name of part |
| (0.0 0.0 0.0) | X, Y, Z insertion point for this part |
| 1.0 | X axis scale factor for this part |
| 1.0 | Y axis scale factor for this part |
| 1.0 | Z axis scale factor for this part |
| 0.0 | X/Y plane rotation angle (radians) for this part |
| FACE | KEYWORD: FACE |
| TRUCK_BACK1_1 | Name of facet |
| painted_steel_side | Material name assigned to this facet |
| 27 | Material ID assigned to this facet |
| truck_back1 | Facet name [unused] |
| -1.0 | Facet temperature (-1.0 means computes) |
| 0.01 | Facet thickness [cm] |
| 1.8 | Facet self-generated power [unused] |
| 1.0 | Facet exposed area [unused] |
| null | [unused] |
| null | [unused] |
| null | [unused] |
| GEOFACE | KEYWORD: GEOFACE |
| (0.000000 152.400000 30.480000) | Vertex #1 Coordinates |
| (0.000000 0.000000 30.480000) | Vertex #2 Coordinates |
| (53.340000 0.000000 30.48000) | Vertex #3 Coordinates |
| (53.340000 152.400000 30.48000) | Vertex #4 Coordinates |
| POINT | GEOFACE POINT |
| (0.000000 0.000000 -1.000000) | Normal vector |
| EOFACE | KEYWORD: EOFACE |
| FACE | Another facet |
| TRUCK_BACK_12 | |
| EOFACE | KEYWORD: EOFACE |
| EOPART | KEYWORD: EOPART |
| PART | Another part |
| TIRE_1 | |
| EOOBJECT | KEYWORD: EOOBJECT |
| OBJECT | Another object |
| ROAD_1 | |
| EOOBJECT | KEYWORD: EOOBJECT |
| EOSCENE | KEYWORD: EOSCENE (Last line in file) |