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Previous issue date: 2014-02-25 / Panoramic rendering is the visualization of three-dimensional objects in a virtual environment
through a wide viewing angle. This work investigated if the use of panoramas
is able to promote faster searches in a virtual environment. Panoramas allow the presentation
of space through less need to change the orientation of the camera, especially for
the case of projections spanning 360? surrounding the user, which can benefit searching.
However, the larger the angle, more distorted is the visualization of the environment,
causing confusion in navigation. The distortion is even bigger when the user changes
the pitch of the camera, by looking up or down. In this work we developed a technique
to eliminate specifically the distortions caused by changes in pitch, which was called
hemispheric projection. Experiments were done to evaluate the performance of search
navigation through perspective, cylindrical and hemispherical projections. The results
indicate that navigating with perspective projection is superior than navigating with panoramic
projections, possibly due to factors such as (i) lack of experience of the participants
in understanding the scenes displayed as panoramas, (ii) the inherent presence of distortion
in panoramic projections and (iii) a lower display resolution because the objects are
presented in smaller sizes in panoramic projections, making the perception of details more
difficult. However, the hemispherical projection was better than the cylindrical, indicating
that the developed technique provides benefits for navigation compared to current techniques
of panoramic projection. The hemispheric projection also provided the least amount
of changes of camera orientation, which is an indication that the hemispheric projections
may be particularly useful in situations where there are restrictions on the ease to change
the orientation. Future research will investigate the performance of cameras interactions
on slower devices, such as using only keyboard, or brain-machine interfaces / Renderiza??o panor?mica ? a visualiza??o de objetos tridimensionais em um ambiente
virtual atrav?s de um largo ?ngulo de vis?o. Este trabalho procurou investigar se a
utiliza??o de panoramas ? capaz de agilizar buscas em um ambiente virtual. Panoramas
permitem a apresenta??o do espa?o atrav?s de uma menor necessidade de modificar a orienta??o
da c?mera, principalmente para o caso de proje??es que englobam os 360 que
cercam o usu?rio, o que pode beneficiar as buscas. Contudo, quanto maior o ?ngulo, mais
a visualiza??o do ambiente ? distorcida, provocando certa confus?o na navega??o. A distor??o
? ainda maior quando o usu?rio modifica a inclina??o da c?mera, ou seja, ao olhar
para cima ou para baixo. Neste trabalho foi desenvolvida uma t?cnica para eliminar especificamente
as distor??es provocadas pela mudan?a de inclina??o, a qual foi denominada
proje??o hemisf?rica. Foram realizados experimentos buscando avaliar o desempenho na
navega??o de busca atrav?s das proje??es em perspectiva, cil?ndrica e hemisf?rica. Os
resultados indicam que a navega??o por proje??o em perspectiva ? superior a navega??o
por proje??es panor?micas, possivelmente devido a fatores como (i) pouca experi?ncia
dos participantes em compreender cenas exibidas de forma panor?mica, (ii) a inerente
presen?a de distor??o nas proje??es panor?micas e (iii) a menor resolu??o de visualiza??o,
pois os objetos s?o apresentados em tamanhos menores nas proje??es panor?micas,
dificultando a percep??o de detalhes. Contudo, a proje??o hemisf?rica se demonstrou melhor
do que a cil?ndrica, indicando que a t?cnica desenvolvida proporciona benef?cios para
navega??o em compara??o com as t?cnicas de proje??o panor?mica atuais. A proje??o
hemisf?rica tamb?m proporcionou a menor quantidade de modifica??es da orienta??o da
c?mera, o que ? um ind?cio de que as proje??es hemisf?ricas podem ser particularmente
?teis em situa??es onde existem restri??es na facilidade de alterar a orienta??o. Pesquisas
futuras investigar?o o desempenho das c?meras sobre dispositivos de intera??es mais
lentos, como o uso apenas de teclado, ou interfaces c?rebro-m?quina.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/18689 |
| Date | 25 February 2014 |
| Creators | Brand?o, Daniel Soares |
| Contributors | CPF:47337761368, http://lattes.cnpq.br/4022950700003347, Campos, Andr? Mauricio Cunha, CPF:00761944700, http://lattes.cnpq.br/7154508093406987, Oliveira, Jauvane Cavalcante de, CPF:46168834330, http://lattes.cnpq.br/4054756781423727, Santos, Selan Rodrigues dos |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Sistemas e Computa??o, UFRN, BR, Ci?ncia da Computa??o |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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