Settings

TunnelCAD has two levels of settings: project settings that are stored in the .tun file, and application settings that persist across sessions in a local configuration file.

Project settings dialog

Open the project settings dialog via File > Settings…. The dialog has a category list on the left and an editor panel on the right.

Project Settings page

• Project Name – the display name for the project, shown in the tab caption.

• Tunnels – a read-only grid listing all tunnel alignments in the project. Tunnel names can be edited directly in this grid.

Units page

See Units for the full description of unit settings available on this page.

Tunnel settings dialog

Open the tunnel settings dialog by double-clicking a tunnel in the project tree, or by right-clicking a tunnel and selecting Settings…. This dialog has three tabs.

General tab

Field	Description
Name	Tunnel name (unique within the project)
Description	Free-text metadata
Start Chainage	Beginning station value
End Chainage	Ending station value
Style	Alignment display style name

Line Definitions tab

A grid for managing measured line definitions. Each row represents one line definition with the following columns:

Column	Description
Name	Line identifier (used in cross-sections)
Layer	Drawing layer assignment
Color	Display color (double-click to open the color picker)
Dev. Line	Deviation reference line (dropdown of all measured and template lines)
Style	Section line style (dropdown from the shared style library)
Draw	Visibility toggle (checkbox — single-click to toggle)
Closed	Whether the line forms a closed polygon (checkbox — single-click to toggle)

Use the toolbar buttons to manage definitions:

• Add – creates a new measured line definition (prompts for name).

• Delete – removes the selected definition and all its data from every cross-section.

• Rename – changes the name of the selected definition across all cross-sections.

• Style Editor – opens the section line style editor to create or modify styles in the shared library.

Warning

Deleting a line definition removes all measured data for that line from every cross-section in the tunnel. This cannot be undone.

Template Lines tab

A grid for managing template line definitions with the following columns:

Column	Description
Name	Line identifier (used in templates)
Layer	Drawing layer assignment
Color	Display color (double-click to open the color picker)
Draw	Visibility toggle (checkbox — single-click to toggle)
Closed	Read-only checkbox, mirrors the template geometry’s closed state

Use the Add and Delete buttons to manage template line definitions. Deleting a template line removes its geometry from all templates.

Application settings

Application-level settings are stored in a JSON configuration file:

• Linux: ~/.config/TunnelCAD/settings.json

• Windows: %APPDATA%\TunnelCAD\settings.json

These settings include:

• Canvas background color – the background color of the drawing canvases.

• Window position and size – restored on next launch.

• Recent files list – the most recently opened project files.

Debug logging

TunnelCAD includes a built-in debug logging system for troubleshooting. To enable it, add "debugLog": true to the settings.json file:

{
  "debugLog": true
}

When enabled, timestamped log entries are written to iqcad_debug.log in the application directory. The log uses flush-per-write, so entries survive crashes. Logging is always compiled into the application but remains dormant until explicitly enabled.