3D ePortfolios: Challenges and Opportunities for the Display of Interactive Models of Building Designs

Robina Hetherington and Kevan Williams University of Central Lancashire

{REHetherington@uclan.ac.uk, KWilliams@uclan.ac.uk}

Abstract Architects conceive buildings as three dimensional

forms, often developing their designs using 3D CAD [Computer Aided Design] or visualization software. Yet their designs are usually presented to each other and to their clients as two dimensional artifacts: such as images or movies created from their CAD models.

In computing, interactive three dimensional worlds are ubiquitous, in particular in the fields of Gaming and Social Networking involving MUVEs [Multi-User Virtual Environments] such as Second Life.

This work explores the options available to students, whose work is primarily designed in three dimensions, to present their work digitally through 3D ePortfolios. It makes recommendations from a range of possible solutions as to the most suitable for the implementation of online ePortfolios which contain interactive models of building designs.

Keywords--- 3D ePortfolios, WWW, CAD

1 Introduction

Architectural design work is usually mounted on large 2D display boards which are difficult and expensive to move around. However, the designs are often generated using 3D modelling and visualization software such as SektchUp, Revit or 3ds Max. The design can be rendered out as a video of, for instance, a fly through or around the design. This, however, loses the flexibility and interactivity that a 3D model can facilitate. A model will enable the user to examine one aspect in detail, or look at the building from another angle. Providing this degree of interaction on computers, by clients and employers, without the software used in the generation of the design, can be difficult with additional software required to enable them to be viewed. In addition, most exhibitions or portfolios require the inclusion of supplementary contextual information.

This work examines, using the examples of student work, the alternative technologies available for the development of 3D ePortfolios, the challenges they

present and presents a plan for their implementation with a small group of Architectural Technology students in a University scenario.

2 3D ePortfolios

This section explores the concept of the ePortfolio in relation to published work and establishes the research goals.

2.1 ePortfolios

There is a considerable body of research into the use and creation of ePortfolios. [1] JISC has supported significant research into the use of ePortfolios, but primarily in the context of personal development planning and continuing professional development. [2]

There are three types of ePortfolios: the ‘learning portfolio’ which documents a student’s achievement; a ‘credential portfolio’, used for registration or certification purposes, and a ‘showcase portfolio’ used by students to supplement a CV. [3] The subject of this work falls within the latter category, in which the student uses it to show or evidence their achievements. The creation of the ePortfolio itself also develops skills and reflective practices which add to the student’s personal and professional development. [1]

An ePortfolio offers practical benefits to the student; the work is easy to store and retrieve, it gains longevity as it can be added to as their career progresses. It is very portable and less costly than creating display boards. The work can be made both available to a wider audience, but at the same time secure, by the use of password protection technologies. [1] The development of the skills required and understanding of the transfer and organisation of information and data on the Internet can make the student more attractive to employers, especially in difficult economic times. [4]

A significant advantage that an ePortfolio has over a traditional paper CV is that in addition to text, graphic, audio and video material can be included. [1] However, the development of a suitable interface to contain and navigate the content of the ePortfolio is complex, requiring a different and more sophisticated approach to

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that of simply creating an on-line version of the 2D displays.

The electronic storage and availability, through suitable interfaces, of work by previous cohorts of students can bring significant advantages to the teaching team. The ability to show past examples of work has been demonstrated to raise standards through the students gaining a clearer understanding of what is expected for a particular type of design brief. [5, 6] The institution also gains through the ability to showcase work to prospective students.

2.2 The display of buildings in 3D ePortfolios

There appears to be little research into ‘showcase’ ePortfolios in the visual disciplines and none in the context of adding 3D capabilities. Research into the role of integration of visualization technologies in Built Environment education found that the use of Virtual Reality and 3D immersive environments in teaching and learning was not widespread. However, as a communication tool, VR and 3D visualisation was demonstrated to improve students’ understanding of built environment elements. Exposure to the technology also helped students to become aware of its capabilities and its usefulness during their professional careers. [7]

X3D [eXtensible 3D], an application of XML [eXtensible Markup Language], has been used to create interactive ‘Information Rich’ 3D models of buildings. The models were embedded into web pages with contextual information passed between the model and the text display of the containing HTML [HyperText Mark-up Language] document.[8]

The innovative element of the research described in this paper is the representation of designs of buildings as 3D interactive models embedded within a student’s on-line ePortfolio. This research builds upon work previously carried out into pedagogical applications of 3D. [9]

2.3 Objectives

The first stage in the study of 3D ePortfolios is to establish recommendations regarding suitable technologies. The use of ePortfolios distributed via storage media such as CD and DVDs is relatively well established. However, this study is aimed specifically at web distributions as these would be easier for the student to update and thus remain current. The range of facilities to be considered in selecting the technology are the ability to:

• Play from a Weblink. It is probable that there would be a reluctance by the recipients of discs to load them into computers, but a link in an email presents less of a barrier. It is intended to test this hypothesis in a separate study which will measure perceptions along with an evaluation of the ePortfolios

• Appear quickly on the site visitor’s computer. The ePortfolio, as it will contain graphics and

models, will be large thus streaming technologies will be investigated as a means to speed up the display

• Provide a secure container with password protection

• Be updatable by the user • Enable feedback, for a potential employer to

comment on the work • Provide user-tracking data, to enable the student

and/or staff to measure the effectiveness of the distribution of the Weblink

• Limit the necessity for the site user to install software through the use of server technologies.

3 The technologies

The concept of computer users interacting in an online 3D environment was conceived as early as the 1980s. Books such as Gibson's 1984 Neuromancer and Stephenson's 1992 Snow Crash predicated the widespread use of Virtual Reality. In 1985 Farmer and Morningstar developed the online role-playing game Habitat for the Commodore 64. In 1994 the Web became 3D with the release of VRML (virtual reality modelling language), which reproduces 3D graphics in a browser.[10] However, although there is considerable interest and money being spent on alternative solutions, there is still no “killer application” such as HTML for Information Rich 3D over the Web. The next section outlines and discusses the possible technologies which could be used to create 3D ePortfolios.

3.1 Model generation

The technologies used for the 3D ePortfolios must be capable of accepting models generated by whatever software is used by the student. Architectural practices use a range of CAD software, with Autodesk's CAD products dominating the architectural sector. Graphisoft's ArchiCAD is currently the second most widely employed CAD product.[11] However the picture with Schools of Architecture, where funding for both software and hardware can be problematic, is more complex. Schools of Architecture recognize the need to prepare students for the needs of the profession, yet economic restraints and the desire to teach in a creative manner mean that they use a range of software which may not always reflect that used in industry. [12]

In a survey conducted by the Architect’s Journal, the range of software used in UK Universities was found to be very varied; Microstation, Vectorworks, Bentley, Rhino and Maya, were the most common amongst the schools surveyed. Also used were AutoCad, ArchiCad 3ds Max Studio, Bentley's Generative Components, Revit, Artlantis and Google SketchUp. [12]

At UCLan the Architectural Technology students are taught using a combination of SketchUp, AutoCAD, Revit and 3ds Max. Output from this software can be in either the proprietary file types or exported in a range of

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formats, such as VRML and DXF [Data eXchange Format], each with varying amounts of data retained.

3.2 Display of the model

The 3D ePortfolios require a combination of text, pictures, possibly video, possibly audio, and 3D. Four possible approaches to achieving the display of this material are outlined and discussed in the following sections.

3.2.1 Web technology solutions

HTML, has many advantages, it is relatively easy to author, either by coding or using an editor. It can incorporate all of the 2D media required. However, the provision of the 3D display is more problematic. The main open source Web 3D options are VRML, X3D and Collada [COLLAborative Design Activity]. They can be generated by most of the software identified as being found in Schools of Architecture by exporting the model. In the case of X3D, the exportation facilities are limited, but there is good provision for exportation as VRML which can then be converted to X3D. There are also plugins for many types of 3D software, such as 3ds Max or Maya, that will generate all three file types. Both X3D and COLLADA, because they are defined by an open standard XML schema, are ideal to contain and exchange digital contextual information, which make them suitable for embedding within a webpage. [8]

Figure 1 X3D model embedded within an HTM

document

Figure 1 shows a model in the X3D format, embedded within an HTML document. The model was generated using Blender and displayed using the Flux plug-in [now called Vivaty]. In addition to the normal interactivity provided by the plug-in (rotate, zoom, camera position) this application utilizes sensor detection to dynamically alter the text displayed in the Webpage. It also enables different states (times) of the model to be displayed, controlled by hypertext links within the

Webpage which send messages to the model scene graph. Animation has also been included in this model.

However, there are a number of difficulties with this approach. In particular there will be a requirement to transfer files to a public servers by students and most server administrators would regard this as a significant security risk. There is also the need for the website user to download and install a 3D plug-in. There can be inconsistencies in the display between browsers. In addition there would be a need for the student to be competent in HTML, JavaScript and XML coding. [13]

3.2.2 CAD software

There are a number of propriety viewers capable of displaying 3D models from the major CAD software companies. Autodesk have developed Autodesk Design Review [formerly called DWF Viewer]. Figure 2 shows a student design displayed in AutoDesk’s Design Reviewer. Bentley provide Bentley View. Both viewers provide display, measuring, and printing application for file types such as DGN [DesiGN], DWG, and DXF file formats. Design Review also provides the ability for the user to add notes. Cut-away sections can be created dynamically and shadows displayed on the client. The model can also be viewed in grayscale and Black and White. It is possible to publish Web pages using AutoDesk software which embeds the Reviewer into HTML.

Figure 2 3D model displayed in Autodesk

Design Review

However, these types of viewers have a major drawback for use in ePortfolios which is that they require the user to download and install a piece of software which is not a ‘standard’ plug-in. Also, if embedded within a webpage, there would again be a need for the student to be able to code HTML or use an editor to add other content such as images, text and audio. However, there are no precedents for adding the type of dynamic updating of both the Webpage and the model as discussed in the previous section.

3.2.3 Portable Document Format

PDF [Portable Document Format] was originally created by Adobe Systems in 1993 for document exchange. PDF is no longer a proprietary file format; it

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was officially released as an open standard in 2008. Each PDF file encapsulates a complete description of a fixed-layout document that includes the text, fonts, images, and 2-D vector graphics which compose the document. However, all versions of Adobe Acrobat from version 8 onwards incorporate the ability to display a 3D PDF document.

Figure 3 Printable version of a 3D model

embedded within a PDF document

3D PDFs contain a window, embedded into the document, though which a virtual model can be displayed and manipulated next to other content. On initially opening a PDF with 3D content, the model appears as an ordinary image and will print as such, see Figure 3.

Figure 4 Interactive 3D model in a PDF

document with display controls and Model Tree

The model becomes interactive once it is clicked when a 3D toolbar appears across the top of the window

containing the model, see Figure 4, which shows an interactive model in a PDF document. The toolbar controls give a high level of interactivity, including: play/pause control (for built-in animations), rendering control, lighting, layer/group display. The ‘Model Tree’ control feature allows further exploration of the model through turning ‘on’ or ‘off’ layers or groups within the model. This gives the user the ability to view a complete building model, or selected parts, for instance to see inside the model with external walls or the roof removed (provided the model has been built with the appropriate layers or groups). [14]

Figure 5 Model in displayed as an “Illustration”

render in a PDF document This solution is attractive in that it is relatively easy

to embed the model alongside other content within the pdf document. It affords high level of interactivity and display options which are built into the 3D display and hence do not require coding skills. Figure 5 shows the model set to an “Illustration” render, a feature built into the software. However, although the software to view a 3D PDF is free, the cost of Adobe Acrobat 9 Pro Extended, which is required to create one, is significant, considering 3D modeling software is also required to generate the model. Although the application requires software to be downloaded, it is reported to have nearly 100% penetration. [15] Another benefit is that the display of content is relatively consistent across browsers and platforms. There is some need for the students to develop skills with Acrobat, but these are probably the least demanding of the options.

3.2.4 Multimedia software

The two main multimedia software options are Director and Flash, both now supplied by Adobe. Flash is pervasive across the Web with 99% penetration of the plug-in claimed by Adobe. [16] However true 3D has not been developed into the software, pseudo 3D can be created by ‘stitching’ a number of 2D images together, but this does not generate a true interactive experience.

Director has had good 3D capabilities for a number of years with the ability to import meshes into the application and add behaviors. It is excellent for the

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creation of multimedia content on CDs and DVDs, however, to deliver content over the web requires employing the Adobe Shockwave plug-in. However this may require the user to download the plug-in as, according to Adobe, the Shockwave Player is only currently available on 58.0% of Internet-enabled PCs. [16] There is also the additional cost of the software in addition to that of the 3D modelling application. The students would also have to gain multimedia authoring skills.

3.3 Comparison of alternatives

Table 1 summarizes the comparative strengths of the various solutions. As can be seen, all of the 4 alternatives will enable combination with other media. All solutions will require some additional training/skills from the students, ranging from coding skills to using multimedia software. However, if multimedia or PDF software is used there would be additional costs.

Web

te

chno

logi

es

CA

D s

oftw

are

3D p

df

Mul

timed

ia

No requirement for installation of non-standard software

Cross browser and platform compatibility

Ability to combine with other media

No requirement to develop additional skills

Ease to provide cut-away views of models

No significant cost in addition to 3D software

Animation Shadows Render control Lighting control Level of detail Key Not a good solution OK with major reservations OK with some reservations Good solution

Table 1 Comparison of solutions considered

The quality of the display of the model was relatively consistent. Only CAD viewer displayed shadows, but even those where not of a high quality. 3D PDF allows the user to alter the render and lighting display without requiring significant programming by the developer.

Animation can be achieved by all but the CAD viewers, with varying levels of control built into the viewer. With 3D PDF the developer can select how the model is displayed if the client machine cannot render with the given frame rate, by either slowing down the animation or sacrificing elements of the model. Programming by the developer is required with web technologies to allow any control of animation

Level of detail is handled differently. With web technologies, different versions of the mesh are created within the one model with varying degrees of detail, these are swapped according to the distance the user is from the subject. With 3D PDF there is only one mesh, but the amount of tessellation is set when the model is imported into the document which controls the detail. Thus the developer must decide the quality in advance or simply provide two separate documents: high or low quality with commensurate difference in file size, both created from the one detailed model.

3.4 Server issues

Because the ePortfolios are to be delivered over the Web, there will a need to be for server space. At UCLan, for security and administration reasons, students do not have direct write access to Web space. However, Adobe Acrobat Connect (formerly Breeze) is server software with which it is possible to allow students to place multimedia materials in a relatively secure manner through the use of ‘rooms’ or a space where they can upload their work.

Connect is server software used to create information and general presentations, online training materials, web conferencing, learning modules. The software uses a database back end and Adobe Flash client technologies to present the content to the user. The normal function of the software is to facilitate conferencing and training, however, because of its multi-functionality, it can be used for content storage and management. The management facilities allow many of the server requirements set out above in the objectives, in particular password protected logins, ease of updating and user feedback, without the need for the students to learn new coding skills. In addition the server can be used to stream content to enable rapid display on the users’ computer. Authoring tools such as Flash, Acrobat or Captivate can be used to generate content, making it ideal for ePortfolios. It would be an expensive option, unless already employed for teaching and conferencing purposes, as is the case at UCLan.

3.5 Recommendations

This section sets out a potential system for the implementation of ePortfolios, based on the discussion in the preceding section.

• A range of 3D modelling software such as AutoCad, 3ds Max and Sketchup to generate the models.

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• Adobe Acrobat to generate 3d PDF files and to display models with other content.

• Adobe Acrobat Connect to provide the server support with each student given access to their own space or “room”.

4 Future work

This paper has described the initial phase of a larger project in which the team has established the technological options. The recommendations will form the basis for a pilot study involving final year students of Architectural Technology. The next phase of the project will involve implementing a pilot study and collecting data.

The students will be offered workshops to plan, design and implement their 3D ePortfolios. Questionnaires and structured interviews with students will be carried out. Two surveys are planned, one before and one after the students have created their ePortfolios. It will measure how well the system deals with the student requirements for display of their work. Qualitative questions will be asked, for instance: how important do they consider features such as animation, level of detail or rendering systems.

These surveys will be carried out using Bristol Online Surveys (BOS). The structured interviews, to gauge perceptions, will be undertaken by a member of staff not directly involved in the project to maintain objectivity. The use of multiple perspectives and data sources will be used to provide improved validity.

Structured interviews with local architectural practices will also be carried out to determine what it is that they are looking for in student portfolios and the technologies they would consider using on their own computers. It is envisaged that this would be a small sample, say 5 firms. The research is primarily qualitative, so consequently the richness of the data is important,

5 Acknowledgements

Thank you to Shaun Keeling for the use of his West Kirby model, Tom Craig for the use of his Castle model and Robert Irving for his Serpentine Pavilion model.

6 References

[1] P. Butler, "A Review Of The Literature On Portfolios And Electronic Portfolios", accessed on 18th December 2008,

http://eduforge.org/docman/view.php/176/1111/ePortfolio%20Project%20Research%20Report.pdf.

[2] JISC, "e-Portfolios: an overview ", accessed on 16th December, http://www.jisc.ac.uk/whatwedo/themes/elearning/eportfolios.aspx.

[3] K. Zeichner and S. Wray, "The teaching portfolio in US teacher education programs: What we know and what we need to know," Teaching and Teacher Education, vol. 17, pp. 613-621, 2001.

[4] H. Grierson, "The Internet as a Tool for Communication in Design Projects," CEBE Transactions, vol. 1, pp. 77-90 December 2004 2004.

[5] D. Brutzman and L. Daly, X3D: Extensible 3D Graphics for Web Authors: Morgan Kaufmann Publishing, . 2007.

[6] R. Hetherington, M. O’Doherty, T. Owens, L. Shannon, and C. Beaumont, "Raising Standards: A Dialogic Approach to Improving Computing Students," in 8th Annual Conference of the Subject Centre for Information and Computer Sciences, 2007, pp. 144 - 149.

[7] M. Horne and E. Thompson, " The Role of Virtual Reality in Built Environment Education," Journal of Education in the Built Environment, vol. 3, pp. 5-24, 2008.

[8] R. Hetherington, B. Farrimond, and P. Clynch, "Interactive Web Visualisation of Proposals for Site Developments," in 11th International Conference on Information Visualization, Zurich, 2007, pp. 613-622

[9] J. Bonar-Law, R. Hetherington, L. Parkinson, and T. Fleet, "Situated Learning in a Multi-User Virtual Environment " in The Higher Education Academy Subject Centre for Information and Computer Science's 2008 Annual Conference, Liverpool, 2008, pp. 150-153.

[10] B. Howarth, "Getting over that flat feeling," in The Guardian London, 2008.

[11] Revelation Research LLP, "2008 Architectural CAD User Survey: Summary Report", accessed on 16th February 2009, http://revresearch.co.uk/images/papers/Architectural%20CAD%20Software%20Survey%20Summary%202008.pdf.

[12] K. Alexander, "Digital Knowledge," Architect's Journal, 25 January 2008 2008.

[13] R. Hetherington, B. Farrimond, and P. Clynch, "Embodying and Extracting Data in Web3D Models of Proposed Building Developments," in International Conference on Computer Graphics, Imaging and Visualization (CGIV07), Bangkok, 2007, pp. 528-534

[14] H. Davies, "PDFs ready to enter the third dimension," in Building Design 2008, 2008.

[15] D. Halliday, "Acrobat 3D Enabled Innovation", accessed on 4th March 2009, http://blogs.adobe.com/dougatadobeplm/2007/08/.

[16] Millward Brown, "Shockwave Player Adoption Statistics", accessed on 8th March 2009, http://www.adobe.com/products/player_census/shockwaveplayer/.

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