A Survey of the Landscape Visibility Analysis Tools and Technical Improvements

Abstract

Visual perception of the urban landscape in a city is complex and dynamic, and it is largely influenced by human vision and the dynamic spatial layout of the attractions. In return, landscape visibility not only affects how people interact with the environment but also promotes regional values and urban resilience. The development of visibility has evolved, and the digital landscape visibility analysis method allows urban researchers to redefine visible space and better quantify human perceptions and observations of the landscape space. In this paper, we first reviewed and compared the theoretical results and measurement tools for spatial visual perception and compared the value of the analytical methods and tools for landscape visualization in multiple dimensions on the principal of urban planning (e.g., complex environment, computational scalability, and interactive intervention between computation and built environment). We found that most of the research was examined in a static environment using simple viewpoints, which can hardly explain the actual complexity and dynamic superposition of the landscape perceptual effect in an urban environment. Thus, those methods cannot effectively solve actual urban planning issues. Aiming at this demand, we proposed a workflow optimization and developed a responsive cross-scale and multilandscape object 3D visibility analysis method, forming our analysis model for testing on the study case. By combining the multilandscape batch scanning method with a refined voxel model, it can be adapted for large-scale complex dynamic urban visual problems. As a result, we obtained accurate spatial visibility calculations that can be conducted across scales from the macro to micro, with large external mountain landscapes and small internal open spaces. Our verified approach not only has a good performance in the analysis of complex visibility problems (e.g., we defined the two most influential spatial variables to maintain good street-based landscape visibility) but also the high efficiency of spatial interventions (e.g., where the four recommended interventions were the most valuable), realizing the improvement of intelligent landscape evaluations and interventions for urban spatial quality and resilience.

Spatio-Temporal Experience of Tour Routes in the Humble Administrator’s Garden Based on Isovist Analysis

“…In the future, combining isovist 3D with 3D scanning technology can be carried out to reconstruct the entire garden's three-dimensional landscape. Then, integrating the model with isovist 3D analysis techniques can be conducted to achieve a more intuitive and three-dimensional analysis of the spatio-temporal experience along the routes [70,71].…”

A Transect Method for Promoting Landscape Conservation in the Climate Change Context: A Case-Study in Greece

“…In this regard, specific viewpoints within the delineated landscape areas were identified which offer representative views of the landscape, and these views were assessed using a standard protocol. Evaluation utilized the landscape assessment protocol [17], which has been used under various assessment frameworks in recent years [72]. The visual assessment is a critical part of the field survey and the scoring of the fifteen metrics provided by LAP can be used independently (i.e., aesthetic attractiveness), in combinations or as a final index.…”

Machine-Learning-Enhanced Procedural Modeling for 4D Historical Cities Reconstruction

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