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TOPAS Graphical User Interface#

The Qt GUI adds a Parameter Control tab to TOPAS for quickly inspecting geometry, tweaking changeable parameters, running sequences, and capturing views. Use it for rapid prototyping; large production runs typically stay batch-only.

Version#

QT5 and QT6 are supported, and the selection of which version will be used by TOPAS is done at cmake time by adding the variables TOPAS_USE_QT and TOPAS_USE_QT6 (there is no default) as follows:

QT5 version active: -DTOPAS_USE_QT=ON -DTOPAS_USE_QT6=OFF
QT6 version active: -DTOPAS_USE_QT=ON -DTOPAS_USE_QT6=ON

The docker image only supports QT5

Enable the GUI#

Build TOPAS with Qt/OpenGL available. The GUI auto-activates on some platforms when OpenGL is requested when you add in your parameter file:
```
b:Ts/UseQt = "True"
```
Optional: to keep the default Geant4 Qt widgets use the following parameter, otherwise the TOPAS tab replaces them.:
```
Ts/IncludeDefaultGeant4QtWidgets = "True"
```
Run TOPAS normally; the Qt window opens with the TOPAS tab added.

Mouse controls (graphics window)#

Top-row Geant4 Qt icons control interaction: pick, zoom in/out, move (pan), rotate, perspective view, orthogonal view and exit. Use these to explore the scene while adjusting parameters.

Parameter Control#

Required-parameter prompts#

The “Select Component Type” dropdown is editable with type-ahead search.
When adding components from the GUI, any known required parameters are collected up front in a dialog.
String fields are auto-quoted if you omit quotes; numeric fields still expect units when applicable.
Leaving a field blank skips adding that parameter (useful when you plan to supply defaults via include files).

Parameter Control table#

Rows appear for parameters marked changeable: prefix the type with c/ic/dc etc. (for example ic:Ge/MyBox/HLX = 2). Non-changeable variants (i:...) are hidden.
Items in bold are read-only (e.g., geometry type/parent, scorer quantity/component, source type). Booleans use checkboxes; enums use drop-downs; other values are inline-editable with units.

Filter bar above the tree matches names or values. Edits apply immediately; invalid entries revert with a warning.
Hover over a parameter displays its full TOPAS parameter syntax

Context menu and duplication#

Right-click a geometry or source header in the tree to duplicate it.
Duplicate Geometry copies a component; you can override translation/rotation before creating the copy. Duplicates have not changable parameters.
Duplicate Geometry Tree copies a component and all descendants using a chosen prefix while remapping parents inside the subtree.
Duplicate Source is available only before the first run. Scorers cannot be duplicated because key scorer parameters are read-only.

Notes and tips#

Added components/scorers/sources start with suggested names; change them before creation if desired. A read-only notice can be suppressed via “Don’t show again.”
Save files from the GUI can be included in later runs to replay a GUI session in batch mode or as a starting point for scripted runs.
TsDicomPatient: when creating a geometry component using DICOM ensure that the image-to-material conversion parameters match with the name of the new component. E.g., in the examples/Patient/ files, the component name “Patient” is used, and HUtoMaterialSchneider.txt has parameters associated to this.
Extra sequence files listed in Ts/ExtraSequenceFiles run after the main sequence when you press Run.

Geometry Extensions#

User-defined Geometry Extensions can self-register via TsGeometryHub::RegisterGeometryType, so their types appear in the GUI selector automatically and can declare required fields for prompting.
All registered types are listed in the GUI; user-defined extensions built with -DTOPAS_EXTENSIONS_DIR=... shown heir own parameters.

Example: registering an extension component#

Add a small register in your component’s code before the constructor (recommended)

#include "TsGeometryHub.hh"
#include "TsMyCustomComponent.hh"

namespace {
  struct RegisterMyCustomComponent {
    RegisterMyCustomComponent() {
        TsGeometryHub::RegisterGeometryType({
            "TsMyCustomComponent",  // Canonical GUI name
            [](TsParameterManager* pM, TsExtensionManager* eM,
               TsMaterialManager* mM, TsGeometryManager* gM,
               TsVGeometryComponent* pgc, G4VPhysicalVolume* pv,
               G4String& childName) {
                return new TsMyCustomComponent(pM, eM, mM, gM, pgc, pv, childName);
            },
            /* DefaultsCreator */ nullptr, // optional; seed defaults if desired
            {   // Required-at-creation params; leave DefaultValue "" to force a GUI prompt
                {"s:Ge/{child}/InputFile", ""},  // string will auto-quote if user omits quotes
                {"dc:Ge/{child}/Size", "1. cm"}  // example with a default
            }
        });
    }
  } registerMyCustomComponent; // static instance
} // namespace

TsMyCustomComponent::TsMyCustomComponent(TsParameterManager* pM, TsExtensionManager* eM, TsMaterialManager* mM, TsGeometryManager* gM, TsVGeometryComponent* parentComponent, G4VPhysicalVolume* parentVolume, G4String& name) {;}

Notes:

Placing the register in the component’s .cc ensures registration happens when the extension is loaded; no changes to core are needed.
Use RequiredParameters to drive the GUI prompt; defaults are auto-added only when provided.

TOPAS Graphical User Interface#

Version#

Enable the GUI#

Mouse controls (graphics window)#

Parameter Control#

Toolbar actions#

Required-parameter prompts#

Parameter Control table#

Context menu and duplication#

Notes and tips#

More on extra sequence files#

Geometry Extensions#

Example: registering an extension component#