How can I achieve photographic 3D environments on the Web?
QTVR is a type of movie file format that enables users to navigate photo-quality scenes. There is a 360 degree range of vision, although the movie displays are small: 320×240 pixels.
You can create panoramas or objects; panoramas can be zoomed to see details, while clicking and dragging is used to interact with objects. Mouse movements simulate the effect of turning your head in any direction — correct perspective is maintained as the user moves his viewpoint.
Images can be more detailed than rendered-on-the-fly 3D, because they are produced from scanned photographs or are pre-rendered scenes.
Apple’s compression technology means the scenes only require a few hundred kilobytes of space, so they can be downloaded fairly rapidly. Multiple nodes throughout the scene enable the viewer to shift viewpoints and move from room to room.
Creating the QTVR movie requires Apple’s authoring software, which costs $549, plus special photographic equipment and a Macintosh with at least 40MB of RAM. (The QuickTime Authoring Suite is designed for use by experienced photography/multimedia development teams; it’s not an end-user product.)
Viewing the scene requires a special player, freely available for Windows or Mac, from the Apple site: qtvr.quicktime.apple.com. If you want to combine panoramas with objects, you need to use an authoring package such as Hypercard 2.3, Apple Media Tool 2.0, Supercard 2.5 or Macromedia Director.
It is not possible to view the scenes or models with a VRML browser. It is possible to encapsulate a QTVR scene in a Director production and then use Afterburner and Shockwave to display it over the Internet.
Examples of QTVR available on the Web are fascinating, once you have downloaded the viewer and waited for the series of images to migrate onto your own machine. A wider audience has experienced the “Star Trek: The Next Generation Interactive Technical Manual” created by Peter Mackey as a CD-ROM, using Macromedia’s Director to present the QTVR environments.
3D Builder from 3D Construction Company is a Windows-based approach to creating models from photographs. In contrast to Apple’s SDK and its advanced photographic gadgetry required to produce suitable photographs, 3D Builder is simple to use and accepts regular 35mm photographs.
These photos do not need to be produced on carefully leveled equipment — the advanced math mapping functions within 3D Builder take care of image analysis and seam matching. Photos can be scanned in (as TIFF, JPEG, BMP and many other formats) or sourced from photo CD or digital camera. Plotting points are transferred from a grid onto the image, then 3D Builder analyses the geometry.
Single photos or multiple photos of large complex objects can be used to create wireframes of 3D models, sets, or interiors. Tools are provided to help you locate lines, points or faces of interest in your photos’ sources. Points in common to a series of pictures are identified for linking purposes. Then the conversion calculation is done and the 3D image is ready.
The file can then be exported to a rendering program or, the photos used to generate the solids can be used as texture maps to recreate the objects within 3D Builder. (Perspective correction is automatic.) In either case the finished scene or model can be exported as a VRML file. Touch up tools are available to edit texture maps directly.
To assess the quality of the conversion to 3D, the image can be viewed as input and as calculated — the vertices and axes are shown.
System requirements are modest: 386 or higher PC with 8MG RAM and any of the three Windows flavors. The program exists in a stand-alone version only (no IPAS for 3DStudio users), but it does have a preview mode, so modeling program users can assess the finished result before importing the model into their program.
3D Builder is the result of five years of development work by Carolyn Merritt, a freelance programmer based in Tennessee. She is reticent about what is “under the hood” of her product, refusing to even divulge what language was used in its authoring. She will say only that the program consists of very tightly integrated code, which Intel is very happy about.
The “math solver,” which is the heart of the program, combines a large number of geometry parameters from 2D images to produce the 3D result. Considering the size of her company and the size of the big fish eyeing it acquisitively, Carolyn has a secret a lot of people want to get their hands on. So far she has refused to consider offers to buy her company.
To view demonstrations of 3D Builder and to download a demonstration version of the software, visit 3D Construction Company’s Web site: www.3dconstruction.com. The full version costs $595 and comes with a manual tested by a seventh-grader for comprehensibility. Upgrades are planned (at low prices) to include a wish list of features from many companies and users.
Another authoring system used to create 360 degree views and models in Windows (but not in VRML) is the Virtual Reality Explorer (VRXplorer 2.0).This software was developed using the Asymetrix Multimedia Toolbook 3.0 by Paolo Tosolini. The Toolbook is a visual programming system using object-oriented design and an OpenScript compiler to enable rapid production of interactive applications.
The Multimedia version has a multimedia engine that can handle sound, video and animation. These capabilities have enabled VRX’s author to produce an author and a player, both of which are currently free, for research purposes only. Useful features for the Web include hotspots that link a behavior to a location and trigger either a video to play, music to be heard, a move to a new location or link to a new URL.
The software takes eight different images, each one shot horizontally at the same level at 45 degree intervals in a circle. Images at higher and lower elevations can also be included in the 8×4 2D array generated by the program. The player displays the images one at a time in the direction of view requested by the user.
To create Web products you will need additional resources from the Multimedia Toolbook, so this product does have its overhead. It is also dependent on the author’s skills in photography to line up the separate images correctly. It is an ingenious way to give the impression of VR, and its hotspots make it impressive in use. But the creation process does not give you the immersive effect achieved far more simply by 3D Builder in VRML, and you will still need a separate special viewer to see the scenes on the Web.
Find out more about VRX by visiting its Web site.