Method for detector description conversion from DD4hep to Filmbox

TL;DR

The paper tackles the mismatch between DD4hep-based detector descriptions and widely used industry 3D tools by introducing an automatic DD4hep–FBX converter. It maps DD4hep’s shapes, transformations, materials, and hierarchy into FBX’s polygonal surface-based representation, enabling direct import into Unity or Unreal for visualization, design, and outreach. Demonstrations on the CLIC full detector and sub-detectors for STCF and CEPC show faithful geometry transfer, with performance metrics indicating scalable conversion (tens of thousands of elements, hundreds of thousands of polygons) and practical trade-offs for large models. This work democratizes access to industrial visualization pipelines for HEP, facilitating detector visualization, simulation visualization, and outreach through VR/AR and cross-platform deployment.

Abstract

DD4hep serves as a generic detector description toolkit recommended for offline software development in next-generation high-energy physics~(HEP) experiments. Conversely, Filmbox~(FBX) stands out as a widely used 3D modeling file format within the 3D software industry. In this paper, we introduce a novel method that can automatically convert complex HEP detector geometries from DD4hep description into 3D models in the FBX format. The feasibility of this method was demonstrated by its application to the DD4hep description of the Compact Linear Collider detector and several sub-detectors of the super Tau-Charm facility and circular electron-positron collider experiments. The automatic DD4hep--FBX detector conversion interface provides convenience for further development of applications, such as detector design, simulation, visualization, data monitoring, and outreach, in HEP experiments.

Figures (16)

• Figure 1: Components of DD4hep detector geometry toolkit dd4hep_paper.
• Figure 2: Simple toy detector described with DD4hep and displayed in ROOT.
• Figure 3: Half sphere described by the mesh in FBX.
• Figure 4: Display of the BESIII detector in Unity with detector geometry data converted from GDML.
• Figure 5: Detector data flow in conversion from DD4hep to FBX.