Journey Into 3D #3

Last post I mentioned about terms & jargons used in 3D production. Here it is plus some other stuff too.

While modelling you'll come across words like Mesh, Polygon, Vertex, Edgeloop, Spline, NURBS, Patch, etc. I will try my best to tell you what it all means by breaking it down into category. But first of all, I'll tell about modelling methods available.



Polygonal & Sub-Division Modelling
This is my fav method. It is more like sculpting really. You take a block of basic shape and start shaving & adding polygons to form a more or less a complete shape. This is still blocky. Then come the Sub-Division level. Most 3D apps have a function to sub-divides your coarse polygons into smaller, more refine polygons. Some called it Meshsmooth/Turbosmooth. Some called it simply Subdivision.
Pros: Like sculpting, you can create almost anything with it. Iterative workflow meaning you could start with a stick and work up until its a sword or something. Very good for animation.
Cons: You need to have a clean mesh from the start to achieve a good final shape. I'll explain more later.



Patch Modelling
Patch modelling is like warping/wrapping/molding a thin, stretchable sheet into shapes. Take a square sheet, and pull the center edge out and you'll get a rounded edge. pull the center upward and you get a mound. Yes now you can model a pillow.
Pros: Very good for something curvy and smooth like...a pillow.
Cons: Very hard to get good sharp edges.



NURBS Modelling
It stands for Non-Uniform Rational B-Splines. Using NURBS make me feel like a scientist or something :). Anyway, it is much like Patch modelling but more mathematically intensive. NURBS (i like how it sounds...) work by taking math coordination functions like XYZ value and use tangent and stuff. Very genius-like. And very heavy on your computer.
Pros: same as Patch. More refine control and advanced toolset
Cons: same as Patch. Heavy




Spline-based Modelling
It is also called spline-cage modelling. Imagine you build a skeletal base, say a Hindenburg Zeppelin (that caught up in fire), then you apply sheets of coverings to the cage. You'll get a Zeppelin! (minus fire. that I will tell how to do later)
Pros: Tweakable, fairly accurate, almost able to build anything with a defined shapes.
Cons: The cage need to be in correct order and have corresponding 'support' cages. Organics modelling is somewhat tedious.


Next I will post more on this subject. So stay tuned *sips coffee*