Advanced CAD & Research Seminar: Readings: Spalter, Wesley, & Kalay Reading Response and Modeling Assignment---Topic: 3D modeling

Summary:

The book chapters “Building 3D Worlds-3D Geometric Graphics I” (Spalter & Wesley) and “On Geometric Modeling” (Kalay) deal specifically with mechanisms of computer aided 3D modeling tools and the pros and cons of each. Topics include volumetric sculpting, primitives, sweeps, polygonal meshes, NURBS, Boolean operations, digital clay/3D sculpting, sketch, and hierarchies. All of the operations benefit the field of interior architecture and its design process because of the 3d modelers they contain. Volumetric sculpting is achieved when “tools act like 3d painting brushes and erasers to buildup and sculpt away material” (Spalter & Wesley,1999). Primitives are premade general 3D shape tools like a sphere, cone, cube, torus, cylinder, a banana, and a dodecahedron (Spalter & Wesley,1999). All of these shapes are tools within 3D modeling programs. Sweeps include several commands, such as revolving, extrusion, and lofting (Spalter & Wesley,1999). Polygonal meshes describe the geometry of an object (Spalter & Wesley,1999). Digital clay/3D sculpting occurs when “pushing and pulling on the vertices and connecting lines of the object’s polygonal mesh” (Spalter & Wesley,1999). Sketch “produces 3D polygonal models” based on the user’s hand movements (Spalter & Wesley,1999). Hierarchies deal with more mechanical operations by organizing “model components by their ability to control each other” (Spalter & Wesley,1999).

Contextualize:

The benefit of these 3D modeling tools directly relates to interior architecture’s design process for product design. The utilization of the applications allows the designer to view products overall, generally, in-depth, and extremely realistically. 3D modeling acts as a visualization tool. Volumetric sculpting helps to build organic shapes, which are generally asymmetrical and much more difficult to achieve with other commands (Spalter & Wesley,1999). Primitives work well when an object possesses an overall symmetrical shape buildable with simplified objects. Instead of forming a primitive shape using several steps, it is done in one, delivering faster results. Sweeps allow for a similar time savings. A solid shape forms from designating the direction for the silhouette line of an object to follow. After drawing the 3D shape, the object’s surface contains a polygonal mesh. The process of NURBS uses the polygonal mesh containing nodes that a designer highlights and moves to contort and manipulate the object’s shape, a much simpler way to alter the object than with pen or pencil. Boolean operations “makes complex models by joining simpler ones (Kalay, 2004). These Boolean operations make any part of “a computational solid model” contain a measureable “surface, volume and other geometric properties” (Kalay, 2004). “Digital clay/3D sculpting enables designers to actually build upon or subtract from an object by using a pen tool that identifies the surface with pressure resistance that the modeler feels. Sketch acts as a digital sketchbook page for designers. Lastly, hierarchies demonstrate the actions of a moving or mechanical product.

Arugment:

Even with the usefulness of 3D modelers, there are some pitfalls. The design programs allow designers to attach a multitude of information into one file, yet too much information creates extremely large file sizes. It’s not as difficult as a physical model to make changes to, explore, and are easily “shared among interested parties indifferent geographical locations at the same or different times” (Spalter & Wesley,1999). The design process for thinking turns to generating new outcomes from avenues we may have never explored otherwise (Spalter & Wesley,1999). In addition, modelers like Sketch, complete object assemblies by automatically grouping components, unlike a physical model (Spalter & Wesley,1999). The display of objects is extremely realistic, such as with displaying textures. However, the display device used for viewng a 3D model is still 2D (Spalter & Wesley,1999). Also, the user’s feelings about the interaction with a space or product can only be assumed in any model or animation. Even topics that sound easy, like Boolean modelers are much more difficult to achieve because it depends on the complexities of the objects and what steps have been done prior to the operation. Many of these programs want to be all things for all people, but with the diversity within the design industry, many times the ability of each to help create and render lacks for certain disciplines. Therefore, the tools should never replace other forms of idea generation, but rather partner with to help push the imagination and process.

Evidence:

The argument that 3d modelers should be an additional tool and not the primary used for design exploration is because there are program issues that the 3D model still cannot address, whether due to program limitations or ‘operator error’. An example is Sketch. The hand renderings it produces seem accurate, but it has no numeric input so the 3D models are “only approximate models of a final ideas” (Spalter & Wesley,1999). In addition, Boolean operations cannot model all shapes (Spalter & Wesley,1999). This means with a digital print, separate shapes would need to made and attached, just like a physical model. Some of the most powerful information designers gather is user interaction, and currently the Behavior modeling models an object’s behavior, such as a stone falling to the ground if dropped, moving in an arc through the air when thrown, or colliding with other objects. Behavior modeling models come the closest in animating articulated attributes (Spalter & Wesley,1999).