PC and Mac 3DMF Software
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Stereogram
Software Windows and Macintosh: The digital representation of 3D or 3DMF geometries (that is, finding suitable data structures with which to maintain spatial data) through software can be challenging, to say the least. Realbasic makes working with 3DMF objects in an RB3D space on a mac or windows uncomplicated and efficient. Traditionally, 3D graphics programmers have come at the "geometry representation" problem either by encoding shapes implicitly (using pure mathematics), or by representing shapes explicitly, via large grids or meshes. (The 2D analog to this situation is vector versus bitmap graphics.) The advantages of the pure-math approach include efficient use of RAM and resolution independence. This is what the 3DMF format and Realbasic do. The chief disadvantage of this approach is lack of flexibility: It's often just not practical to try to represent complex shapes in terms of, say, NURB patches. (NURB stands for non-uniform rational B-spline, and a patch is a surface based on curves. A somewhat more flexible alternative to implicit 3DMF modeling is explicit representation of geometry through vertex arrays. This time-honored approach has the advantage of letting the programmer model shapes of arbitrary complexity, to any desired degree of accuracy (RAM permitting). The downside of the brute-force 3DMF software "big mesh" method should be obvious: For all but the most trivial objects and scenes, we're talking about huge amounts of array indirection, array reallocation, and array storage. Even if RAM is no problem, managing all that 3DMF array data can be a nightmare. Most programmers would agree that the only reasonable way to approach this kind of data-manipulation 3d software nightmare is to impose an object paradigm on it, so that data is hidden when necessary, visible when necessary, and the division of responsibilities between and among objects can be known in advance and enforced. This is the approach taken by QuickDraw 3D 3DMF. QD3D 3DMF is an object-based system, in that just about everything is an object with a position in a well-defined hierarchy. Don't be put off by this if you're not an object-oriented programmer. To use 3DMF QuickDraw 3D, you don't have to know a bit of C++, because the API is entirely implemented in procedural C. (A Pascal interface is also available; check Apple's web site.) Realbasic is a great alternative. What's important here is that by encapsulating geometric data and methods in objects, Apple has succeeded in hiding a lot of the ugly details of geometry manipulation (and storage) from the programmer, while enforcing uniform behavior, yet allowing access, when necessary, to 3DMF objects' internals. And the good news is, you can use implicit or explicit geometries, or both. QD3D accommodates conics, quadrics, quartics, and NURB patches, as well as a rich set of polyhedral-mesh tools -- the best of both worlds.
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All of the below examples were made with 3D Maker:
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