# Creating Audio Object-Focused Acoustic Environments for Room-Scale Virtual Reality
## 3 Methods  
The paper proposes a multimodal, (audio) object-focused methodology for the creation of acoustic environments presented in room-scale VR. Generally, the methodology builds on the production cycle of game audio, as described in [24; 50], but affects steps in the sound generation and implementation process. Traditionally, surrounding ambiences would be created in a digital audio workstation (DAW) and the mixed result is imported as a single sound file (or a collection of sound files corresponding to stems/tracks of this audio mix) into the audio middleware/game engine for playback [5]. This approach means that the structure and parts of the mix of the acoustic environment would be defined in the DAW, with the audio middleware providing \begin{table}
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**Title** & **Type** & **6-DoF** & **6-DoF Audio** & **Diegetic Music** & **Generative Music** & **Surrounding Ambiances** & **Music Mapping** \\ \hline Virtual Virtual Reality 2[9] & Adventure & yes & partial & no & no & yes & no \\ \hline Half-Life: Alyx [17] & FPS shooter & yes & partial & partial & no & yes & object \\ \hline Zylia Concert Hall [19] & Music & yes & yes & yes & no & no & avatars \\ \hline [PERSON] et al., 2021 [21] & Music & yes & yes & yes & no & no & level meters \\ \hline [PERSON] et al., 2018 [6] & Music & yes & yes & yes & no & no & avatars \\ \hline [PERSON] et al., 2020 [25] & Music therapy & n/a & n/a & n/a & no & n/a & visualizations \\ \hline The Climb 2 [26] & Sport & yes & partial & no & no & yes & no \\ \hline The Mage’s Tale [27] & Action RPG & yes & partial & no & no & yes & no \\ \hline [PERSON] et al., 2016 [34] & n/a & n/a & n/a & no & evolutionary & n/a & visualizations \\ \hline Washburn and Khosmod, 2020 [35] & n/a & n/a & n/a & n/a & multi-agent expert system & n/a & visualizations \\ \hline Spore [36] & Simulation & no & no & no & rule-based & yes & objects \\ \hline Beat Saber [41] & Music & yes & partial & no & no & multimodal \\ \hline
12 Sentiments & Music & n/a & partial & partial & n/a & no & multimodal \\ \hline Rez Infinite [47] & Music & no & no & partial & rule-based & music & multimodal \\ \hline Eleven Table Tennis [48] & Sport & yes & yes & yes & no & n/a & object \\ \hline Vacation Simulator [43] & Simulation & yes & yes & partial & no & yes & object \\ \hline Please, Don’t Touch Anything! [49] & Puzzle & yes & partial & partial & no & yes & object \\ \hline \hline \end{tabular}
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Table 1: Comparison of differences and similarities of the cited experiences/papers regarding 6-DoF audio, generative audio, diegetic music, and the mapping of the music’s features to other senses or objects, i.e., visualizations of rhythms or representation by visible objects. “n/a” is entered if there is not sufficient information available to identify a characteristic. some degree of flexibility over audio playback via adaptive audio. This process would lead to the issues mentioned in the paper's introduction. In contrast, the paper's approach uses the DAW to produce a (detailed) collection of sound files corresponding to localized, single audio objects or point sources of an acoustic environment instead. Each object would be associated with an event in the audio middleware, and its playback and real-time effects are defined by rules, which are specified in the game engine. The game engine, thus, implements the structure of the acoustic environments and uses the audio middleware predominantly as a sample player rather than as a sequencer. In this way, the paper combines an object-focused approach with multimodal rule-based systems and adaptive and 3D binaural audio in 6-DoF. The governing system defines an object's behavior on all its sensory, interactive, and spatial representations using rules, as conceptualized using the example representations in Figure 1. In this way, object behaviors can be defined in many modalities and mapped to sounds by the designer.