Drawing equirectangular VR panoramas with ruler, compass, and protractor

This work presents a method for drawing Virtual Reality panoramas by ruler and compass operations. VR panoramas are immersive anamorphoses rendered from equirectangular spherical perspective data. This data is usually photographic, but some artists are creating handdrawn equirectangular perspectives to be visualized in VR. This practice, that lies interestingly at the interface between analog and digital drawing, is hindered by a lack of method, as these drawings are usually done by trial-and-error, with ad-hoc measurements and interpolation of pre-computed grids, a process with considerable artistic limitations. I develop here the analytic tools for plotting all great circles, line images and their vanishing points, and then show how to achieve these constructions through descriptive geometry diagrams that can be executed using only ruler, compass, and protractor. Approximations of line images by circular arcs and sinusoids are shown to have acceptable errors for low values of angular elevation. The symmetries of the perspective are studied and their uses for improving gridding methods are discussed

Cadavre Exquis: motion-controlled interactive film

This interactive film, a variation on the surrealist game Cadavre Exquis, seeks the possibility of subverting the filmic discourse by exploring psychosomatic processes that may give the viewer different perceptions of cinematic time, by providing the possibility of intervening into the narrative in a disruptive way.info:eu-repo/semantics/publishedVersio

Spazi digitali e modelli immersivi: applicazioni di prospettiva cubica

Composition exercises of increasing difficulty are aimed at assessing the acquisition of the rules of cubical perspectives previously elaborated. The built environments were made immersive thanks to dedicated software. The operator is thus virtually projected into the centre of the cubical space and is, therefore, free to visualize the entire space to analyse each aspect considered. The experience allows to self-correct the discontinuity errors made in the execution of cubical perspectives which become evident in the virtual space. It also enables to verify the quality of the extracted/abstracted composition rhythms, as well as inductively adjust the ratios and proportions of the sketched elements. Amongst the achieved objectives, the main result is a significant step forward in the use of analogue/digital methods for an architectural drawing for cognitive, conformative and communicative purposes.Applicazioni di difficoltà crescente mirano a valutare l’acquisizione delle regole di prospettiva cubica precedentemente elaborate. Gli ambienti costruiti con questo metodo sono stati resi immersivi con l’ausilio di software dedicati. L’operatore è virtualmente proiettato al centro di uno spazio ideale è quindi libero di visualizzare l’interno per analizzare gli aspetti rappresentati. L’esperienza permette allo studioso di auto-correggere gli errori di discontinuità commessi nell’esecuzione piana resi evidenti nella simulazione virtuale. Il sistema consente, inoltre, di verificare la qualità dei ritmi di composizione architettonica estratti/astratti, nonché di modificare induttivamente i rapporti e le proporzioni degli elementi abbozzati. Tra gli obiettivi raggiunti, un significativo passo in avanti nell’utilizzo integrato dei metodi analogici/digitali ai fini conoscitivi e dunque, conformativi e comunicativi. Tra gli obiettivi prefigurati, la promozione di nuovi metodi e categorie per esplorare in modo concreto le potenzialità future della rappresentazione architettonica

Legendrian varieties and quasi-ordinary hypersurfaces

Tese de doutoramento, Matemática (Geometria e Topologia), Universidade de Lisboa, Faculdade de Ciências, 2011This thesis is a study of the Legendrian Varieties that are conormals of quasi-ordinary hypersurfaces. In the first chapter we study the analytic classification of the Legendrian curves that are the conormal of a plane curve with a single Puiseux pair. Let m,n be the set of Legendrian curves that are the conormal of a plane curve with a Puiseux pair (m, n), where g.c.d.(m, n) = 1 and m > 2n, with semigroup as generic as possible. We show that the quotient of m,n by the group of contact transformations is a Zariski open set of a weighted projective space. The main tool used in the proof of this theorem is a classification/construction theorem for contact transformation that has since proved useful in other instances. In the second chapter we calculate the limits of tangents of a quasi-ordinary hypersurface. In particular, we show that the set of limits of tangents is, in general, a topological invariant of the hypersurface. In the third chapter we prove a desingularization theorem for Legendrian hypersurfaces that are the conormal of a quasi-ordinary hypersurface. One of the main ingredients of the proof is the calculation of the limits of tangents achieved in chapter two.Fundação para a Ciência e Tecnologia, Portugal, PRAXIS XXI/BD/15915/98

revista de Ciências da Arte

Organizando-se agora no formato de número duplo, de modo a comportar dois números por ano, a revista digital Convocarte – Revista de Ciências da Arte mantém o mesmo propósito de promover o debate e edição de questões artísticas no espaço universitário, mantendo as coordenadas dominantes: convocar um número de especialistas em torno de um tema do mundo das artes, integrar trabalhos relevantes desenvolvidos nas fases curriculares e de projecto em mestrados e doutoramentos, sobretudo da FBAUL, e publicar trabalhos desenvolvidos em linhas de investigação do CIEBA. Assim, embora de funcionamento afecto à área científica de Ciências da Arte e do Património a Convocarte está aberta a outras especialidades interessadas em contribuir para a reflexão sobre as artes em geral, incorporando ensaios de predomínio teórico enraizado nos mais predominantes modos de discurso sobre arte, tais como História da arte, Crítica de Arte, Estética, Teorias da Arte ou Curadoria. (...) O nº2 organizou-se em torno de uma homenagem a uma figura importante das teorias da arte em Portugal, estratégia que Convocarte procurará manter nos próximos números. A intenção será deixar estudos sistematizados, entre o depoimento ou o ensaio, a memória e a reflexão, que estudem figuras marcantes da cultura portuguesa. (...) Neste número essa pasta foi dedicada a Rui Mário Gonçalves. Os textos são o resultado de uma sessão especial alargada a 2 de Maio no âmbito dos 2ºs Encontros com Críticos de Arte, com organização e coordenação de Fernando Rosa Dias, Cristina Tavares e Viviane Soares Silva, e decorridos ao longo das segundas do mês de Maio de 2016 na FBAUL (http://convocarte.belasartes.ulisboa.pt/index.php/2016/04/29/2o-encontros-com-criticos-de-arte/#more-325). A partir destes trabalhos reuniu-se um conjunto de estudos em torno de Rui Mário Gonçalves, com depoimentos e estudos sobre as mais diferentes facetas desta importante figura da cultura portuguesa: crítico de arte, historiador de arte, curador artístico, pedagogo e professor, político e activista, etc. A Convocarte orgulha-se de publicar os textos dessas comunicações, acrescentado de outros estudos, agradecendo a todos os colaboradores deste evento, que consideramos uma pasta que adianta contributos dando continuidade a estudos no catálogo de homenagem e no âmbito de apresentação da colecção do crítico de arte na SNBA, realizada pouco antes na SNBA.info:eu-repo/semantics/publishedVersio

MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

Plantar povoações no território: (re)construindo a urbanização da capitania do Piauí, 1697-1761

The Piauí province´s urbanization has kept up with since late 17th century a complex process dealt among Portuguese Crown, the regal representatives, the network woven by the Casa da Torre and by the resident population in its countryside. What it was content of Rodelas countryside has begun to build with territorial identity since the foundation of first parish in 1697. Structuring itself discontinuously in time and space, the Piauí had reformed in 1758, year of creation of its autonomous government. And had became urban in 1761 when the king D. José I and marquis of Pombal had framed by the royal letter written in June 19 a territory formed by six towns and one city. Thus, this paper purposes to reconstructing the Piauí province according to agents involved in the urbanization processes. It proposes to deconstructing Crown´s polices by means towns strategically placed in territory aiming at control and "remedy" of routine injustices practiced in Piauí´s hinterlands. The method of presenting this reconstruction draws on interconnection between text (manuscript documents) and image (maps and photography) which in their discourses have represented a Piauí as space of experiences apprehended as much in official dimension as inhabitant´s everyday life.A urbanização da capitania do Piauí acompanhou, desde finais do século XVII, um complexo processo negociado entre a Coroa portuguesa, os representantes régios, a rede clientelar urdida pela Casa da Torre e a população residente em seus sertões. O que antes era conteúdo dos sertões de Rodelas passou a construir-se como identidade territorial a partir da fundação da primeira freguesia, em 1697, dedicada a Nossa Senhora da Vitória. Estruturando-se descontinuamente no tempo e no espaço, o Piauí reforma-se em 1758, ano da autonomização do seu governo. E fez-se urbano em 1761, quando D. José I e o marquês de Pombal equacionaram, por meio da carta régia de 19 de junho, um território formado por seis vilas e uma cidade. Nessa direção, o objetivo deste artigo consiste em reconstruir o processo de formação da capitania do Piauí segundo os agentes envolvidos na urbanização do território. Propõe-se descortinar as políticas da Coroa por meio da oficialização de povoações estrategicamente locadas no território visando o controle e o "remédio" das injustiças rotineiras do Piauí. O método de apresentar essa reconstrução vale-se da interconexão entre texto (documentação manuscrita) e imagem (mapas e fotografias), que em suas entrelinhas representam um Piauí como espaço de experiências sentidas tanto na dimensão oficial quanto no cotidiano dos seus moradores

Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

Topologia, anamorfose, e o bestiário das perspectivas curvilíneas

Faz-se uma breve digressão pelo catálogo das perspectivas curvilíneas centrais, descrevendo algumas das suas propriedades topológicas, geométricas, e ópticas, enfatizando a sua ligação com o conceito fundamental de anamorfose com vista a esclarecer alguns equívocos clássicos relativos à posição fundamental ocupada pela perspectiva clássica.info:eu-repo/semantics/publishedVersio

Reconstruction of St. Michael’s Church, Hildesheim in cubical perspective

A method that considers cubical perspective as a special case of spherical perspective was recently presented in (Araújo et al. 2020). We recall and apply this descriptive geometry-based construction to the case study of St. Michael’s Church, Hildesheim. Some key elements of the church are used as a reference problem to introduce further details of the method, such as how to efficiently plot spatial points or make on-the- fly variations of the reference system while drawing. The purpose is to show the potential and solutions provided by the full method and to feature some fundamental properties of cubical perspective