the channels menu / get intercol

channels menu

get intercol

Purpose
To read files in GIG's own Intercol format.

Introduction
GIG 3DGO and GIGVIZ feature a custom interpreted scripting language called Intercol. This Intercol used to be accessible to GIG users, but was encapsulated in later versions.

However, it still can be convenient to be able to read Intercol files. This is the case when special tools (e.g. converters) produce data in Intercol syntax. You can use this option to read such a file. Intercol files are commonly suffixed with the .int extention.

Preparation
The get intercol feature expects its input files to be in the intlib directory. This can either be the intlib directory in your ~/lib/intlib or ~/projects/my_prj/intlib. The file name must have the extension .int (in lower case).

Example

Assuming the user is currently in the directory where the Intercol file is stored, the Intercol file has the name test.int and the user's project is named 'convert', then the following command has to be executed:

cp test.int ~gig/projects/convert_prj/intlib

The intlib directory of the currently active project could also be accessed using the environment variable LD:

Example

mv test.int $LD

This command will move the file test.int to the intlib directory of the currently active project.

Usage
Now a copy of the Intercol file has been placed in the correct directory, select the get intercol button from the channels menu in the GIG interface. The selection submenu will then be displayed where you can make your selection.

Unexpected appearance of Nurbs models in GIG
Many CAD systems use B-spline or Nurbs surfaces to write their data to file. The default representation of Nurbs in the GIG interface is the Nurbs control polygon. This polygon often does not resemble the actual shape of the object. Choosing another display mode will show a better representation of the Nurbs.

In some cases, a Nurbs object will be regarded as 'solid' when it should be 'hollow' or the other way around. For example, a hollow cylinder in a CAD system might appear as a solid cylinder, with end planes, in GIG. In this case you can toggle the solid/hollow box in the solid construct menu for each individual Nurbs object.

Large CAD files
Sometimes a CAD model that has been converted to Intercol format produces a model that is too large for the standard configuration of GIG. In these cases, stack overflow error messages can appear while reading the Intercol file. Usually, this can be solved by copying a configuration file with larger configuration values to your home directory. This will cause GIG to require more swapspace. The large configuration file should not be necessary for Intercol files of less than 10 MB.

Example

Assuming the user is currently in the GIG home directory, then the following command has to be executed:

cp lib/intlib/confile.big confile

Restart GIG and convert the IGES file as described above.

Comments
Intercol files come in two versions: a crypted unreadable format and a human-readable ASCII format. Only the crypted format is accessible to customers.

The Intercol file format can describe much more than just model geometry. Parts of the GIG program itself are defined in Intercol. Such files can be found in the lib/intlib and projects/library_prj/intlib directories; they do not contain model information and should not be imported through the use of the get intercol button. Trying to read random Intercol files can cause random results.