3. Converting From/to ASCII
With the implementation of BRL-CAD’s machine-independent database format, the need for converting to or from ASCII format has rapidly diminished. Nonetheless, BRL-CAD still supports ASCII conversions, and release 6.0 introduced a new ASCII format. This format is simply a Tcl[1] script that (when executed by a properly empowered Tcl interpreter) rebuilds the database from which it was derived. In contrast, the old ASCII format consisted of a sequence of one-line records that corresponded to the old database format records.
1. Converting From ASCII
The asc2g
utility is used to convert ASCII format databases into the
new binary format. This utility will always create the new binary
format, but it will accept either of the two ASCII formats.
The usage for this utility is as follows:
asc2g
input.asc output.g
In this command, input.asc is a file previously created using
g2asc
and output.g is the name where the resulting binary
database should be stored.
2. Converting to ASCII
The converse of the asc2g
utility is the g2asc
utility, which is
used to convert from either the current database format or the
prerelease 6.0 database format to an ASCII format. Databases in the
new format will be converted to the new (Tcl script) ASCII format.
Databases in the old format will be converted to the old ASCII format.
The command for this utility is as follows:
g2asc
input.g output.asc
In this command, the input.g is a BRL-CAD database (old or new format) and output.asc is the name where the ASCII output is placed. As mentioned previously, the form of the ASCII output depends on which database format is used by the input database. If it is known that the input database is in the older BRL-CAD format, then the g2asc may be executed using redirected input and output, as follows:
g2asc < input.g > output.g
If this is attempted using the newer database format, however, an error message will be displayed and no conversion will be performed.