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Digital Ornament

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Digital Ornament Digital Ornament John Elys University of Wales Institute Cardiff / University of Lincoln Abstract Gaming software has a history of fostering development of economical and creative methods to deal with hardware limitations. Traditionally the visual representation of gaming software has been a poor offspring of high-end visualization. In a twist of irony, this paper proposes that game production software leads the way into a new era of physical digital ornament. The toolbox of the rendering engine evolved rapidly between 1974-1985 and it is still today, 20 years later the main component of all visualization programs. The development of the bump map is of particular interest; its evolution into a physical displacement map provides untold opportunities of the appropriation of the 2D image to a physical 3D object. To expose the creative potential of the displacement map, a wide scope of existing displacement usage has been identified: Top2maya is a scientific appropriation, Caruso St John Architects an architectural precedent and Tord Boonje’s use of 2D digital pattern provides us with an artistic production precedent. Current gaming technologies give us an indication of how the resolution of displacement is set to enter an unprecedented level of geometric detail. As modernity was inspired by the machine age, we should be led by current technological advancement and appropriate its usage. It is about a move away from the simplification of structure and form to one that deals with the real possibilities of expanding the dialogue of surface topology. Digital Ornament is a kinetic process rather than static, its intentions lie in returning the choice of bespoke materials back to the Architect, Designer and Artist. Introduction disappeared from the early modern designer’s lexicon, today advanced Gaming and CAD visualization modeling and CNC technologies will software share a diversity of program allow ornament back onto the center usages, each area has its selective stage. There is considerable potential for methodology on which parts of a program the resurrection of surface (D) texture/ it adopts, a particular modeling tool, a decoration within architecture, art and rendering capability or its animation design. capabilities. Software providers have made This area of research originated from provisions for all areas of production, a student request to create a meshed and this has in turn promoted an eclectic screen for a final year CAD visual. The overlap. Advances in gaming resolution easy option was to create a checker will figure heavily in the forthcoming transparency map to represent the years, leading software provision into mesh of the proposed screen, but there a sophisticated dialogue of increased were issues with that method of virtual topology. Historically, decoration representation. A checker transparency 68 would create the effect of a mesh on a advancements of the virtual world cannot planar object, but it would not be able be appropriated to become physical to carry the shadowing properties of a objects. Today, the texture map is far from modeled mesh object. The question arose being just a mere image-based activity; it that there must be a way of harnessing the has evolved into a powerful tool for the technology of D visual representation, in geometric displacement of topology. This this case the transparency map, to create introduces an exiting era of unparalleled a physical artifact rather than an illusion, detail, which in itself is quite ironic, and there must be a quicker method of considering the checkered history of construction. There always is. virtual representation. The appropriation of the visual D representation into a D model is the Texture Maps aim of the current research, and to explore and highlight the possibilities available. With such a large resource of D Why texture map? In the quest for more maps created for image production, the realistic imagery, one of the most frequent possibilities are endless - always a positive criticisms of early-synthesized raster thing for creativity. The basic toolbox images was the extreme smoothness of the render engine is not an exclusive of surfaces – they showed no texture, CAD Visual element; it appears in many bumps, scratches, dirt or fingerprints. genres of virtual representation, employed Realism demands complexity, or at least differently per incarnation. Gaming and the appearance of complexity. Texture animation are examples of the differing mapping is a relativity efficient means usage but they employ a different working to create the appearance of complexity methodology to that of the CAD visual without the tedium of modeling and Despite the differences between CAD rendering every 3D detail. (Heckbert visual elements animation and gaming, they 1986). do share the same rendering components in the creation of the desired effect. The Texture mapping is in essence research breaks down the complexity of an automated process to replicate a usage into the bare components. From complexity of surface. It is an important its early origins in 976, [this is as early historical precedent from which we can as it gets for the modern day Computer] get the first insight into the imaginative the texture map has become not just an processes developed by the early pioneers image-based activity; it has developed of textural reality. To date, the technique the potential to generate complexity of has remained a visual representation that detail once unimaginable. Is it time to avoids the tedium of physically modeling revisit the role that visualization, gaming the surface of D objects. In the early days and computer animation have in the real of virtual representation, a toolbox was world? formed to enhance the plain surfaces of The world of computer generation the computer D model. This was very is often referred to as the virtual world; much an image-based activity, employed to there is no reason why some of the produce an effect of realism. John Elys Digital Ornament 69 In 986, Paul Heckbert of Pixar Bump Map Evolution surveyed the use of texture mapping, and considering the hardware and software Jim Blinns paper “Simulation of available at that time, it was no surprise Wrinkled Surfaces” published in 978 is that there was so much methodology an iconic paper documenting his research developed in the world of visualization. [invention] into the making of what is Over a short 0-year period the major widely known now as a bump map. It components of today’s rendering software signaled for the first time a progressive environment were formed. Between movement towards the appearance of 97 and 985 texture mapping evolved true complexity and realism in the CAD from being a singular method of mapping environment. Pre 978 visualization and color onto a d object, to a multitude of gaming had lived in a flat raster based user-defined attributes. Figure 1 helps to world. illustrate and define the factions of the Blinn employed a technique that typical rendering palette. It is interesting mapped a grayscale D image to the that this collection of ‘effects’ are based surface of the D object. The grayscale on the original collection of advancements map is employed with a lighting module listed by Paul Heckbert in 985, and are to determine the height of the image very much still in use in today’s rendering based displacement, the white end of and animation programs. the grayscale determined the height of the displacement and the arrangement, • Surface Colour [Ed Catmull 97] and graduation of the source image • Specular reflection [James Blinn file determined the overall effect of 976] displacement of the surface. In essence, • Bump mapping [James Blinn978] the grayscale map is a height map used by • Transparency [Geoffrey Gardner the render engine in displacing the pixels 985] in the image rather than displacing the • Diffuse reflection [Gene Miller geometry of the actual object. 98] • Surface Displacement/ shadows maps [James Kajiya 85] (Heckbert. 1986). Figure 1. From left to right the application of a color map to a sphere. Figure 2. Bump mapping example. ACADIA 2006: Synthetic Landscapes Digital Exchange 70 Digital Making: Superficies: Integral and Applied Displacement mapping bump map on the left is heavily reliant on not only the grayscale map but on the lighting employed to define the image Displacement mapping is a further displacement. Bump mapping works well advancement in Blinn’s technique. It is as a means of imaging topology but the directly related to bump mapping in representation becomes more obvious the that it also uses a height map to model closer you get to it with the camera view. surface perturbations. The difference, A Bump map resides somewhere between however, is that displacement mapping image and surface. actually modifies the surface geometry, The image on the right is computed whereas bump mapping only affects using the displacement map method. The the normal vectors. In other words, displacements are worked out by physically displacement mapping adds geometric displacing the geometry of object to that detail to the mesh (Nuydens 00). of the map. In order to keep an effective workflow the actual displacement is not Polygon displacement can provide fully employed as physical polygon model, us with physical [virtual] surfaces of rather it acts as a geometrical code at the geometric complexity. It is true that the rendering stage. The difference in surface level of processing power, along with topology is self-evident; the displacement the complexity of mesh needed to gain appears physical rather than an effect a detailed object, can be overwhelming, and at close quarters, the sphere retains especially for animation and gaming. accurate topological detail. However, the evolution of the bump map into displacement is the initial stage of a Displacement baking process that automates the modeling of highly detailed objects; a process that does Displacement baking is a term used to away with the tedium of having to model describe the conversion of a displacement every little detail.
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