GEOD

Commands

GEOD builds a geological cross-section from information entered by the user in a script written in a language specific to GEOD. This language is based on a relatively small set of commands, which can be grouped into several categories.

Basic geometric primitives

These commands are used to insert the main geometric elements required to construct a geological cross-section.

• point — adds a point to the cross-section.
• line — draws a polyline, for example to define the topographic profile.
• bezier — draws a Bézier curve, which is especially useful for quickly tracing a layer boundary or a fault.
• text — inserts text into the cross-section.

Geometric transformation commands

These commands automatically generate new geometries from previously defined curves or structures.

• offset — constructs an offset curve from another curve according to the thickness specifications provided by the user. This command is used to build layers of constant thickness, as well as variable-thickness units such as wedges or lenses.
• shift — constructs a translated version of another curve. This command is especially useful for drawing similar folds.
• bezoff — constructs a deformable Bézier curve. This command is particularly useful for animations, especially when layers need to be folded progressively.

Clipping and filling commands

These commands are used to restrict drawing operations to a given region of the cross-section, or to fill geological units with patterns.

• clip ... unclip — defines clipping masks. Any GEOD instructions placed between clip and unclip are restricted to a specific part of the cross-section, for example below the topographic profile and between two faults. These commands are therefore essential for constructing the section compartment by compartment.
• pattern — fills a layer with a lithological pattern. This command makes it possible to draw a pattern that remains consistent with the geometry of the layer boundaries.
• fill — fills a region with a general fill pattern, for example a small cross pattern for a granitic pluton.

Commands controlling the global properties of the cross-section

These commands define the general scale and layout of the drawing area and of the printed output.

• input — specifies the scale of the cross-section in the GEOD drawing area.
• output — specifies the printing scale of the cross-section.
• scale — enlarges or reduces the cross-section in the GEOD drawing area.
• origin — moves the origin of the drawing area, that is, the lower-left reference point.

Additional commands

The following commands are used to define variables, add legends, and enrich the graphical content of the cross-section.

• set — defines variables. In GEOD, a variable can store a numerical value or an array of values. Variables can also be used to store information related to lithological or fill patterns. They are particularly useful when one or more parameters are reused several times in the same cross-section.
• box — draws a box that can be filled with a lithological or fill pattern. This command is useful for constructing legends and title blocks.
• log — adds a log to the cross-section.

How to use this section

The command system of GEOD is intentionally compact, but many commands include numerous subcommands and options. In practice, the richest and most flexible commands are usually pattern and fill, because they control the graphical rendering of geological units.

To make navigation easier, each command is documented on a dedicated page with its syntax, main options, and examples of use. Use the links above to access the detailed documentation for each command.

Command reference