th2-tool

Small Python CLI to modify Therion .th2 files generated from TopoDroid to work better with Therion cartography style, and .th centerline files.

Quick Start

Run the script directly:

python3 th2_edit.py <file.th|file.th2|directory> [command] [options]

From this folder:

python3 -m unittest discover -s tests

If no command is provided for a .th2 file, the script applies all default conversions:

• line pit -> line floor-step
• line chimney -> line ceiling-step -reverse on
• line rock-border -> add or force -close on

For .th files, the script performs only backsight marking: it marks the station-to-station shot immediately after each extend left command as duplicate. This matches TopoDroid's backsight-before-foresight layout, retaining the backsight as survey data while excluding it from Therion's total-length calculation. The .th2 conversions and commands do not modify .th files.

Project Layout

• th2_edit.py: main CLI script.
• tests/: unit tests for conversion and CLI behavior.
• data/: sample and working .th2 files (for example data/AS-1p.th2).

Run commands from the repository root so paths like ./data/AS-1p.th2 work as shown.

Examples

Default conversion (no command):

python3 th2_edit.py ./data/AS-1p.th2 --in-place

Mark backsights in a centerline file (enabled by default):

python3 th2_edit.py ./data/Canyon.th --in-place

Leave .th backsights unmodified:

python3 th2_edit.py ./data/Canyon.th --no-mark-backsights --in-place

Process every .th and .th2 file directly in a directory. Directory input always writes changes in place without creating backups:

python3 th2_edit.py ./data --no-backup

Notes

• --in-place and --output are mutually exclusive.
• Single-file in-place changes create <name>.<extension>.bak by default; unchanged files are not rewritten or backed up.
• Use --no-backup to disable backup creation.
• --mark-backsights is enabled by default for .th inputs; use --no-mark-backsights to disable it.
• Directory input processes only immediate .th and .th2 files, not subdirectories. It always writes changes in place without backups and cannot be used with --output.