Exploring server/web-client event display for CMS

Abstract

The divergence of windowing systems among modern Linux distributions and OSX is making the current mode of event display operations difficult to maintain. In order to continue to support the CMS experiment event display, Fireworks, we need to explore other options beyond the current distribution model of centrally built tarballs. C++-server web-client event display is a promising direction that can maintain the full functionality of Fireworks, including operation from the full experiment framework. In addition, it brings new features like multi-user debugging and the possibility to implement more elaborate visualization of non-event data through remote access to independent services. We have been exploring mainly in the direction of Fireworks-based C++ server and thin web-client user interface as it allows for a large degree of reuse of existing algorithms as well as for full access to CMS data formats and accompanying functions that are crucial for the correct physics interpretation of event data. This paper presents the basic architecture of the system, discusses the communication protocol between server and client, and shows existing prototypes that demonstrate the feasibility of advanced event display features. *

RenderCore – a new WebGPU-based rendering engine for ROOT-EVE

“…Since ROOT version 6 provides a fully C++ standard-compliant interpreter, rootcling, including support for lambda expressions, it was possible to port several high-level Fireworks features into REve: support for physics collections & physics items, physics item filtering, and table-views with custom column expressions. Proof-of-concept implementation and design choices for REve and FireworksWeb were presented at CHEP-2018 [9] (client-server core, data exchange, remote method execution) followed a year later, at CHEP-2019, by a functional prototype of CMS FireworksWeb [10]. Towards the end of 2021, event-display service for CMS was deployed at CERN and at UC San Diego.…”