How sketches work: a cognitive theory for improved system design

Evidence is presented that in the early stages of design or composition the mental processes used by artists for visual invention require a different type of support from those used for visualising a nearly complete object. Most research into machine visualisation has as its goal the production of realistic images which simulate the light pattern presented to the retina by real objects. In contrast sketch attributes preserve the results of cognitive processing which can be used interactively to amplify visual thought. The traditional attributes of sketches include many types of indeterminacy which may reflect the artist's need to be "vague". Drawing on contemporary theories of visual cognition and neuroscience this study discusses in detail the evidence for the following functions which are better served by rough sketches than by the very realistic imagery favoured in machine visualising systems. 1. Sketches are intermediate representational types which facilitate the mental translation between descriptive and depictive modes of representing visual thought. 2. Sketch attributes exploit automatic processes of perceptual retrieval and object recognition to improve the availability of tacit knowledge for visual invention. 3. Sketches are percept-image hybrids. The incomplete physical attributes of sketches elicit and stabilise a stream of super-imposed mental images which amplify inventive thought. 4. By segregating and isolating meaningful components of visual experience, sketches may assist the user to attend selectively to a limited part of a visual task, freeing otherwise over-loaded cognitive resources for visual thought. 5. Sequences of sketches and sketching acts support the short term episodic memory for cognitive actions. This assists creativity, providing voluntary control over highly practised mental processes which can otherwise become stereotyped. An attempt is made to unite the five hypothetical functions. Drawing on the Baddeley and Hitch model of working memory, it is speculated that the five functions may be related to a limited capacity monitoring mechanism which makes tacit visual knowledge explicitly available for conscious control and manipulation. It is suggested that the resources available to the human brain for imagining nonexistent objects are a cultural adaptation of visual mechanisms which evolved in early hominids for responding to confusing or incomplete stimuli from immediately present objects and events. Sketches are cultural inventions which artificially mimic aspects of such stimuli in order to capture these shared resources for the different purpose of imagining objects which do not yet exist. Finally the implications of the theory for the design of improved machine systems is discussed. The untidy attributes of traditional sketches are revealed to include cultural inventions which serve subtle cognitive functions. However traditional media have many short-comings which it should be possible to correct with new technology. Existing machine systems for sketching tend to imitate nonselectively the media bound properties of sketches without regard to the functions they serve. This may prove to be a mistake. It is concluded that new system designs are needed in which meaningfully structured data and specialised imagery amplify without interference or replacement the impressive but limited creative resources of the visual brain

Online region computations for Euler Diagrams with relaxed drawing conventions

AbstractEuler diagrams are an accessible and effective visualisation of data involving simple set-theoretic relationships. Efficient algorithms to quickly compute the abstract regions of an Euler diagram upon curve addition and removal have previously been developed (the single marked point approach, SMPA), but a strict set of drawing conventions (called well-formedness conditions) were enforced, meaning that some abstract diagrams are not representable as concrete diagrams. We present a new methodology (the multiple marked point approach, MMPA) enabling online region computation for Euler diagrams under the relaxation of the drawing convention that zones must be connected regions. Furthermore, we indicate how to extend the methods to deal with the relaxation of any of the drawing conventions, with the use of concurrent line segments case being of particular importance. We provide complexity analysis and compare the MMPA with the SMPA. We show that these methods are theoretically no worse than other comparators, whilst our methods apply to any case, and are likely to be faster in practise due to their online nature. The machinery developed for the concurrency case could be of use in Euler diagram drawing techniques (in the context of the Euler Graph), and in computer graphics (e.g. the development of an advanced variation of a winged edge data structure that deals with concurrency). The algorithms are presented for generic curves; specialisations such as utilising fixed geometric shapes for curves may occur in applications which can enhance capabilities for fast computations of the algorithms' input structures. We provide an implementation of these algorithms, utilising ellipses, and provide time-based experimental data for benchmarking purposes

조경 드로잉의 역사와 디지털 재현의 '포토-페이크'에 대한 비평

학위논문 (박사)-- 서울대학교 대학원 : 조경학, 2017. 2. 배정한.이 연구는 디지털 조경 드로잉의 시각화 테크닉과 컴퓨터 테크놀로지의 이용 방식이 역사적으로 어디서 비롯되었는지를 파악하고, 이를 바탕으로 최근 디지털 조경 드로잉에 나타나는 회화적 사실주의에 대한 열망을 해석하고자 하였다. 구체적으로, 손에서 컴퓨터에 이르는 조경 드로잉 테크닉의 역사를 포괄적으로 검토하고, 드로잉 매체가 손에서 컴퓨터로 이행하는 과정에서 컴퓨터 테크놀로지가 담당했던 역할을 파악한 후, 현재의 디지털 프리젠테이션 드로잉에 만연한 사실주의적 묘사 경향을 비판적으로 진단하였다. 먼저, 손 드로잉의 역사를 검토하여 조경 드로잉의 특성과 변천 과정을 개관하였다. 조경 드로잉은 도구성과 상상성이라는 호환가능하고 상대적인 두 특성을 지니고 있고, 그러한 특성은 투사, 퍼스펙티브 뷰, 다이어그램이라는 구체적 드로잉 유형으로 구현되어 왔다. 이러한 드로잉 관습은 뚜렷이 구별된다기보다 오히려 상호 보완적으로 혼성화되면서 설계 경관에 대한 비전을 시각화해 왔는데, 특히 식물 소재는 회화적 퍼스펙티브 뷰의 형식을 취한 채 투사 드로잉과 혼성화되는 경향이 있었다. 물론, 특정 지역과 시기에 특정 정원 양식에 적합한 드로잉 유형이 등장하고 때때로 우세하는 방식으로 나타났다. 16세기 이탈리아 르네상스 정원과 17세기 프랑스 바로크 정원 설계에는 투사 드로잉이 중요했고, 18세기에서 19세기 초 영국 풍경화식 정원 드로잉에서는 회화적 묘사가 강조된 퍼스펙티브 뷰의 형식이 선호되었다. 19세기 중후반 조경이라는 영역이 확립되어가던 시기의 미국에서 드로잉은 용도에 따라 분화되고 대상지 조사에 적합한 맵 오버레이 기법이 등장하기 시작하였고, 20세기 초중반 미국의 모더니스트는 설계 전략을 시각화하기 위해 다이어그램을 이용하기 시작했다. 하지만 이러한 다양한 드로잉 방식은 그것이 출연한 이후에는 대체로 공존해 왔고, 드로잉의 도구성과 상상성은 종종 상호 보완적으로 혼성화되어 설계 경관을 시각화하였다. 둘째, 현재 조경 설계에 이용되는 주요 시각화 테크닉의 매체가 손에서 컴퓨터로 이행하던 시기를 검토하여 이 때 컴퓨터 테크놀로지가 담당했던 주요 역할을 분석하였다. 대체로 컴퓨터는 손 드로잉의 테크닉을 모방하거나 컴퓨터 파일의 형식으로 번역하는 기계적 도구로 기능했다. 먼저, 경관 정보를 과학적으로 시각화하는 이안 맥하그의 맵 오버레이 기법, 일명 레이어 케이크의 매체가 손에서 GIS 소프트웨어로 이행하는 1970–80년대에, 컴퓨터는 손으로 처리되던 맵 오버레이 분석의 인벤토리, 가치 평가, 시각화를 대신 처리해주는 효율적 기계 도구로 기능하였다. 또한, 캐서린 구스타프슨과 조지 하그리브스는 1980–90년대부터 랜드폼을 스터디하기 위해 물리적 모형을 만들어왔고, 이 과정에서 CAD 소프트웨어는 그러한 모형을 시공 도면이라는 투사 드로잉으로 번역하는 모사 도구로 기능하였다. 1980–90년대 이브 브리니어, 아드리안 허즈, 제임스 코너 등이 만들어온 물리적 재료를 이용한 콜라주와 몽타주 기법도 1990년대 후반부터 포토샵으로 대표되는 그래픽 소프트웨어를 통해 제작되고 있는데, 이 과정에서도 그러한 소프트웨어는 대체로 수작업과 유사한 절차를 처리하는데 이용되고 있었다. 예외로, 제임스 코너는 2001년 프레쉬킬스 공모전 당선작에서 그래픽 테크놀로지의 잠재력을 활용하여 플랜 콜라주라는 테크닉을 발명하고 이를 설계 아이디어를 발전시키는 생성적 도구로 이용했다. 셋째, 최근 디지털 프리젠테이션 드로잉에 만연한 사실주의적 묘사 경향을 비판적으로 진단하였다. 대중과의 의사 소통이 점차 중요해지면서 조경 설계에서 프리젠테이션 드로잉의 제작이 차지하는 비중이 커지고 있고, 여기서 경관의 외양을 사실적으로 묘사하려는 경향이 있다. 조경가는 역사적으로 설계 경관의 외양을 회화적으로 묘사하는 기법에 익숙했고, 포토샵과 같은 그래픽 소프트웨어는 그러한 기법을 효과적으로 처리해내는 도구로 이용되고 있다. 이러한 경향은 사진 합성을 통해 만들어지는 퍼스펙티브 뷰에서 잘 드러나는데, 포토샵의 다양한 명령어를 통해서 사진 재료의 조립 흔적이 지워지고 회화적 환영을 만들어내는 다양한 효과가 덧입혀져 현실의 경관을 포착한 한 장의 사진처럼 보이도록 생산되고 있다. 이 연구는 그러한 시각화 기법과 이미지를 포토-페이크로 정의하고, 근래에 개최된 국제 공모전 출품작의 프리젠테이션 드로잉을 사례로 하여 그것의 구체적 조건을 분석했다. 포토-페이크의 조건은 보이지 않는 프레임과 관찰자의 자리, 환영을 만들어내는 방법, 배경으로서의 경관과 구경꾼으로서의 인물, 그리고 디지털 아우라이다. 포토-페이크 제작에는 이전의 수작업에서 이용되던 테크닉이 재등장하는데, 그러한 기법은 18세기 픽처레스크 미학이나 17세기 역사주의적 풍경화를 비롯한 시각 문화의 영향을 받고 있었다. 포토-페이크 이미지는 대중들의 시선을 쉽게 사로잡을 수 있는 효과적 의사 소통 수단이지만, 동시에 시각 이미지라는 한계 때문에 경관의 다감각적 특성을 온전하게 시각화하기는 힘들다. 따라서 그러한 기법은 조경가의 설계 경관에 대한 비전을 잘 드러내도록 활용되어야 할 것이다. 또한 경관의 외양뿐만 아니라 기능 정보를 시각화하는 삼차원 모델링 기법, 다양한 드로잉 유형과 테크놀로지의 혼성적 이용 방식은 경관의 다채로운 국면을 탐구하고 설계 아이디어를 발전시키는 창조적 도구로 활용될 수 있다. 조경가의 설계 아이디어를 곧바로 현실에 조성할 수 없다면, 그러한 아이디어는 불가피하게 어떠한 형식이든 시각화의 과정을 거치게 된다. 설계 아이디어를 생성하고 발전시켜나가며 동시에 디지털 테크놀로지의 잠재력을 이끌어낼 수 있는 시각화 테크닉의 창조적 실험이 조경 이론뿐만 아니라 실천에서 충만해지길 기대한다.This dissertation explores historical landscape architectural visualization techniques and ways of using computer technology and then offers a critique of the pervasive trend towards realism in the recent digital landscape representation. Specifically, it examines historical representational techniques in landscape design from manual drawings to recent computerized visualsit also explores the role of computer technology in landscape representation during media transition from hand to computer and critically analyses the trends of realistic pictorial depiction in recent digital landscape visualization. Firstly, examining the history of manual drawings, this research provides a comprehensive understanding of the characteristics and functions of landscape representation and historical changes regarding specific techniques. Landscape architectural drawing has double functions, namely, illustration of not-yet-actualized landscapes (i.e. instrumentality) and generation of creative ideas (i.e. imagination), which are relative, interchangeable, and transformable. These characteristics have been embodied in the forms of particular types of drawing, projections, perspective views, and diagrams, whose characteristics are not so much clearly distinguishable as rather mutually complementary and hybridized in such a way that pictorial views of plants frequently are hybridized to projection drawings. Of course, particular drawing types or techniques have often emerged as suitable and thereby dominant forms, depending on particular historical styles of landscape design. Sixteenth-century Italian Renaissance gardens and seventeenth-century French formal gardens were generally visualized in the form of projections. Eighteenth-century and early nineteenth-century English landscape gardens were frequently represented in pictorial perspective view. In nineteenth-century America, the professional identity of landscape architecture started to be established and different drawing types were specialized depending on their respective functions. Furthermore, the map overlay method for site analysis emerged. Twentieth-century American modernists began to explore the diagram to deploy design strategies. However, such drawing types and methods have coexisted after their emergenceinstrumentality and imagination have been frequently hybridized for the visualization of future landscapes. Secondly, this work discusses the early history of the initial uses of major computer software to shed light on the major roles of such technologies in landscape visualization in the period of transition from conventional drawing tools. Computer technologies generally functioned as mechanical tools to imitate previous manual techniques and translate physical media into computer files. In the 1970s to 1980s, the medium of the map overlay analysis of Ian McHarg, namely, layer cake, changed from manual to computerized. In the transition of technologies, the computerized Geographic Information System served as a mechanical tool substituting the hand in that the GIS efficiently used methods similar to manual procedures, including inventory, evaluation, and visualization. Since the 1980s, Kathryn Gustafson and George Hargreaves have used physical modelling, such as sand and clay models, for landform study. In realizing such models on site, the CAD software generally functioned to translate three-dimensional (3D) models to two-dimensional (2D) construction documents, i.e. projection drawings. In the next two decades, landscape architects, including Yves Brunier, Adriaan Gueze, and James Corner, deployed the collage and montage using mixed media and photographic materials. Since the late-1990s, manual techniques have been increasingly produced using graphic editing software, such as Adobe Photoshop, which generally functioned as a tool to perform processes similar to those of manual techniques. In Lifescape, the winning proposal in the Fresh Kills Park competition in 2001, as an exception, Corner fully exploited the potential of graphic software to explore creative visualization techniques, including plan collage, which was used to develop the design idea in the design process. Thirdly, this research offers a critique of the dominant trend towards realism in recent digital landscape representations. Since 2000, in landscape design, presentation drawings adopting a realistic depiction have gained increasing importance in communication with the public. Landscape architects, historically, have frequently used pictorial depictions of the appearance of landscapes as a dominant representational techniqueadvanced graphic editing software, including Photoshop, make it possible to achieve this desire for realism effectively. This trend is epitomized by perspective views using the composite photographic technique. In representations, discernible traces of cutting and assembling are removed, and visual effects are applied to create illusions via various commands and filters in the software. Thus, the complete representations are perceived as if they were a copy of an actual landscape. To refer to such representations, this dissertation coined the term photo-fake, whose several conditions (invisible frame and viewers position, illusions, landscape as theatre and human figures as spectators, and digital aura) were analysed by scrutinizing the visuals of recent international design competitions. These techniques often imitate previous manual methods, which historically date back to at least the eighteenth-century picturesque aesthetics and seventeenth-century historical landscape paintings. Whereas the photo-fake image can easily capture the publics eye, it is difficult for the static visuals to achieve full embodiment of all of the multisensory characteristics of a landscape. Thus, photo-fake techniques need to be exploited to deploy a designers specific vision of the not-yet-actualized designed landscape. Furthermore, digital modelling of landscape performance and various hybridized techniques with different drawing types and technologies provide the opportunity to explore various aspects of landscape and stimulate design ideas during the design process. If a designers vision of a future landscape cannot be immediately realized on the actual site, then such visions inevitably need to be visualized in other forms. Thus, visualization techniques, both to generate creative idea and exploit the potential of digital technology, need to continue to be simultaneously explored in landscape theory and practice.I. Introduction 1 1.1. Research Purpose 1 1.2. Research Objectives and Theoretical Perspective 5 1.3. Literature Review 6 1.4. Structure 11 II. Rethinking the History of Manual Drawing 14 2.1. Hybridization of Instrumentality and Imagination 14 2.1.1. Instrumentality and Imagination 14 2.1.2. Hybridization 24 2.2. Manual Drawings in History 37 2.2.1. Projection: The Italian Renaissance and French Formal Gardens 37 2.2.2. Pictorial Representation: The English Landscape Gardens 44 2.2.3. Diverse Specialization of Drawing: The 19th-century America and Frederick Law Olmsted 51 2.2.4. Emergence of Diagram: Modernism in America 57 III. Technological Transition 63 3.1. Hand and Computer Drawings 63 3.2. Transition from Hand to Computer 72 3.2.1. Scientific Visualization of Landscape Information: Map Overlay Method 72 3.2.2. Landform Simulation: Model Making 88 3.2.3. Exploration of Perspective View: Collage and Montage 100 IV. Digital Landscape Representations Photo-fake 124 4.1. Pictorial in Digital Landscape Representation 124 4.2. Photo-fake 134 4.2.1. Defining Photo-fake 134 4.2.2. Photo-fake Conditions 143 4.2.3. Opportunities and Limitations of the Photo-fake 156 4.2.4. Korean Landscape Architecture 160 4.3. Beyond the Depiction of Appearance 164 4.3.1. Modelling Landscape Performance 164 4.3.2. Hybridization Strategies 172 V. Conclusion 177 Bibliography 180 List of Illustrations 192 국문초록 201Docto