Tile-based Maps Optimization for OM Virtual Environments

  • Bernardo Costa Cefet/RJ
  • Nicolas Nery Cefet/RJ
  • Pedro Henrique Gonzalez Cefet/RJ
  • Windson Viana UFC
  • Joel dos Santos Cefet/RJ


ENA is a mobile application for people with visual impairments who want to improve their Orientation and Mobility (OM) skills. It allows users to load personalized virtual maps of physical spaces, such as school buildings or mazes specially designed for OM training. The maps are created using a tile-based approach and could contain eight layers of tile matrices representing a floor, wall, or other objects. The map elements are enriched with 3D audio clues allowing users who are blind to navigate and accomplish OM tasks. In terms of loading large 3D environments, ENA had some inefficiencies. This performance issue is caused by the tool rendering method. It creates an object for every tile, even if there are contiguous areas of walls or fl oors made from the same material. We have developed two optimization algorithms integrated into ENA to address this issue. The first algorithm works on straight lines, while the second focuses on two-dimensional regions. These algorithms effectively reduce the number of objects created, resulting in a much faster and more efficient ENA tool.

Palavras-chave: Orientation and Mobility, Virtual Environments, Map Optimization


2023. The JSON data interchange syntax. [link].

Seth Chaiken, Daniel J Kleitman, Michael Saks, and James Shearer. 1981. Covering regions by rectangles. SIAM Journal on Algebraic Discrete Methods 2, 4 (1981), 394–410.

Ying Cheng, SS Iyengara, and Rangasami L. Kashyap. 1988. A new method of image compression using irreducible covers of maximal rectangles. IEEE transactions on software engineering 14, 5 (1988), 651–658.

Alex Clark. 2015. Pillow (PIL Fork) Documentation. [link].

Agebson Rocha Façanha, Ticianne Darin, Windson Viana, and Jaime Sánchez. 2020. O&M indoor virtual environments for people who are blind: A systematic literature review. ACM Transactions on Accessible Computing (TACCESS) 13, 2 (2020), 1–42.

Agebson Rocha Façanha. 2021. Customização de ambientes virtuais de orientação e mobilidade para pessoas com deficiência visual. Ph.D. Dissertation. Universidade Federal do Ceará.

Orly Lahav. 2022. Virtual Reality Systems as an Orientation Aid for People Who Are Blind to Acquire New Spatial Information. Sensors 22, 4 (2022). https://doi.org/10.3390/s22041307

Sina Sharif Mansouri, George Georgoulas, Thomas Gustafsson, and George Nikolakopoulos. 2017. On the covering of a polygonal region with fixed size rectangles with an application towards aerial inspection. In 2017 25th Mediterranean Conference on Control and Automation (MED). IEEE, 1219–1224.

G Scheithauer, Yu Stoyan, and T Romanova. 2009. Integer linear programming models for the problem of covering a polygonal region by rectangles. 2 (2009), 4–13.
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COSTA, Bernardo; NERY, Nicolas; GONZALEZ, Pedro Henrique; VIANA, Windson; DOS SANTOS, Joel. Tile-based Maps Optimization for OM Virtual Environments. In: CONCURSO DE TRABALHOS DE INICIAÇÃO CIENTÍFICA - SIMPÓSIO BRASILEIRO DE SISTEMAS MULTIMÍDIA E WEB (WEBMEDIA), 29. , 2023, Ribeirão Preto/SP. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2023 . p. 67-70. ISSN 2596-1683. DOI: https://doi.org/10.5753/webmedia_estendido.2023.235450.