New Reflection Transformation Imaging Methods for Rock Art and Multiple-Viewpoint Display

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Obtención de mapas 2.5D mediante RTI (Reflectance Transformation Imaging) para su aplicación en el Patrimonio Escultórico, Arqueológico, Arquitectónico y Urbano.

Desde los orígenes, el ser humano ha tratado de encontrar métodos que mejoren o posibiliten alcanzar objetivos que el cuerpo humano es incapaz. Aunque éste es altamente complejo, no es perfecto y el ojo humano es limitado en términos de profundidad (visión estereo) y color. Por ello se crea el método de trabajo conocido como Flujo Clásico para RTI, que posibilita extraer información oculta de objetos con mínima variación de cota. 1. Realidad Objeto 2. Toma de Fotos Domo con Luces en determinadas posiciones y Cámara Cenital 3. Generación PTM RTIBuilder (X, Y, Normal Vector) 4. Visor RTIViewer (SnapShot) Este flujo de trabajo parte de un objeto de tamaño pequeño. Al cual se le aplica, junto a un par de esferas reflectivas, una serie de fotografías mediante una cámara cenital y diferentes posiciones de proyección de luz inscritas en un Domo geométrico para mantener las equidistancias a la superficie de análisis. Tras ello se pasa al trabajo en ordenador donde se genera un archivo de superficies de normales (*.ptm o *.hsh) mediante los algoritmos de Polynomial Texture Mapping o Hemispherical Harmonics en RTIBuilder. El cual puede ser analizado mediante el Visor que presenta el RTIViewer. Este Flujo de Trabajo Clásico no puede afrontar factores como la luz natural, transforma las direcciones de la proyección de la iluminación, o las dimensiones del objeto/edificación/terreno a trabajar. Es por ello que se propone el Nuevo Flujo de Trabajo RTI-DPh, la virtualización del Clásico Flujo de Trabajo RTI.Departamento de Urbanismo y Representación de la ArquitecturaMáster en Geotecnologías Cartográficas en Ingeniería y Arquitectur

Parametric Architectural Design Solutions – Some Observed Difficulties of Application

It is generally accepted that the restrictions of digital parametric design tools (DPDT’s) are currently shifting. Technology and interface can be engineered to overcome many complex problems within architectural processes, yet this does not necessarily mean solutions are easier to obtain; quite the opposite can occur. As architectural practitioners lean more towards the ubiquitous use of digital processes the decisions made by the designer can be overshadowed by the advantages of time saving technologies and heuristic rules of thumb. The various inherent interfaces of digital processes tend to conceal the real complexity and nuance of the set of possible solutions and analyses. The awareness of the workings of the tools and processes from a ‘base principle’ point of view could be a weak point in regards to the uptake by a new generation of architects who experience a growing simplification of interfaces within new digital design processes. This poses a problem for a profession which seeks to integrate technical skills knowledge into wider, sometimes loosely structured, set of processes. This research highlights the problems faced by architects, students, and specialists who aspire to apply innovative digital processes in a strategic manner. The concern which arises is this lack of understanding of how tools could be used reduces the ability to integrate them within design process. Theoretical literature falls short in providing robust guidance to the application of illunderstood design tools, further compounding the sincere integration of practical solutions. There are ways forward for developers to create new and updated tools, such as form modellers, design aids, and optimisation helpers, but these do not necessarily meet their full potential in providing integrated solutions. It is possible to improve our understanding of these potentials by looking at how these tools can be used in both practical and theoretical terms. In this thesis this is done by framing and answering the following research question: What are the characteristics of some of the observed issues and obstacles revealed in the practical application of digital parametric design tools in architecture? This question is adopted so that the obstacles of DPDT’s may be better understood and allow for better integration, better design outcomes, and better future use of powerful latent potential. This research defines the process of parametric design through analysis of literature and applies this to participantobserver case studies. It finds that a clarification of particular issues and obstacles can be useful to improved understanding of DPDT’s and that certain qualitative characteristics of these obstacles can constrain applications and avenues of exploration

Realistic visualisation of cultural heritage objects

This research investigation used digital photography in a hemispherical dome, enabling a set of 64 photographic images of an object to be captured in perfect pixel register, with each image illuminated from a different direction. This representation turns out to be much richer than a single 2D image, because it contains information at each point about both the 3D shape of the surface (gradient and local curvature) and the directionality of reflectance (gloss and specularity). Thereby it enables not only interactive visualisation through viewer software, giving the illusion of 3D, but also the reconstruction of an actual 3D surface and highly realistic rendering of a wide range of materials. The following seven outcomes of the research are claimed as novel and therefore as representing contributions to knowledge in the field: A method for determining the geometry of an illumination dome; An adaptive method for finding surface normals by bounded regression; Generating 3D surfaces from photometric stereo; Relationship between surface normals and specular angles; Modelling surface specularity by a modified Lorentzian function; Determining the optimal wavelengths of colour laser scanners; Characterising colour devices by synthetic reflectance spectra