The definition of 3D

[bellinger]

I have been asked to get the opinion of some industry experts...thats all of you....on the definition of 3D

Here are the questions?

Can you present something in 3D on a screen which is in fact 2D?

To be a 3D presentation does an object have to rotate 360 degrees?

Is a photograph not the most relistic 3D image that can be produced?

[wcoleman]

I am surprised that you are not getting any responses. I don't fall into your category of industry experts - I am a college professor who develops a lot of web-based material for uses in my classes (and for anyone else in the world to use freely in theirs) - but I have some definite opinions on your questions, and a lot of experience with how students respond to 3D material.

1. In terms of processing the information there is relatively little difference between a 3D object and a series of closely related (in time and space) 2D views of aspects of that object. In other words, it is the ability to animate these views that makes 3D programming useful.

2. I don't think 360 degree rotation is essential, but some motion to show aspects of the object not accessible with a single shot is needed. If you are going to rotate at all why not do 360 degrees.

3. A photograph that makes good use of light can certainly give a good feel for the 3D character of an object, but both phtographers and artists have clearly demonstrated over hundreds of years (more, obviously for artists than photographers) how easy it is to trick the viewer.

The 3D web applications that are readily accessible to most of us due a decent job of bridging the gap between flat and true 3D. I always spend some time with my students talking about the idea of the presentation of a 2D slice of an nD space and they have no problems with such ideas. Obviously the skill of the designer and the quality of images rendered by the software are key here - a sense of perspective is very useful. When I introduce students to, for example, crystal structures or atomic orbitals, we will look at a variety of 3D renderings of the same thing - solid, wireframe, hidden lines, no hidden lines, perspective, various cases of lighting. What I am trying to do is help the students build a good "BS detector" so that they have the ability to sort out what is really part of the 3D object and what is an artifact of the representation.

Student response to these images is overwhelmingly favorable. It is very difficult for a photograph of any type to truly illustrate the 3D character of complex molecules. We make daily use of 3D molecular structures (visualized via a browser plug-in that reads atomic structure data files) and students quickly develop a far more sophisticated appreciation of 3D molecular structure than was previously possible. Additionally, many people have great difficulty seeing three dimensionality in 2D figures, and some of these people opted out of careers in areas such as mine (chemistry) as they felt their inability to do this was an insurmountable barrier. These people have little if any problem with the 3D images.

There is certainly a lot of literature out there about the physiology and psychology of perception of these images. I look forward to reading other responses.

Peace,

Flick

[St= Z]

Well I think peoples reluctance is rooted in the fact that there is no right or wrong answer, and the question begs a sort of surpufluos and relative answer.

But INMHO

something thats "3D" is anything that actually exists in all three dimensions.

a "3D image" is anything that references a third dimension with a visual cue.

Just my 2c