Beginner's terminology misconception
Hi all, I am a beginner in 3D modeling. I have trouble with the terminology. The term "geometry" appears very often in various videos/articles/documentation, but nowhere is it clearly stated what they mean by it. I've looked up the definition in various software glossaries, just browsed the Internet, looked in various dictionaries, but haven't found a satisfyingly clear answer. It seems to be something obvious to everyone.
For example, Maya refers to geometry: NURBS surface, NURBS curve, subdivision surface, or polygonal surface (mesh), dictionaries suggest translation as configuration, shape or form, spatial attributes. In Blender and Zbrush there is no definition, but they have geometry nodes/geometry. Adobe Start 3D series says that "geometry" is just a part of the 3d model besides lights, shaders and etc. Wikipedia says about Wavefront .obj file format that it just stores "geometry", and then it lists it. Polycount's glossary also has the definition. But each source defines the term differently.
As I understand it, 3d modeling is geometric modeling, that is, we use geometric objects to build a shape. So why aren't all these curves and vertices and stuff just called geometric objects? I haven't found a translation option for "geometry" as geometric objects or primitives. As if it means something else.
From my own paragraph above, I've already made some assumptions for myself. But it is nothing more than "kind of". What if I'm missing something? I think I just can't translate it into my native language to make it sound understandable.
English is my second language, in my native language "geometry" is various branches of the mathematical sciences.Perhaps it's just jargon/abbreviation or the term has a broader meaning in English.
Please help me understand, thanks in advance for your help.
Replies
When people say geometry, they just mean the vertices, edges, and faces that make up the visual surface of the model. It is not a precise technical term.
I think maya is classifying all of these different types of things together as geometry because they are just different methods to create the same end result. Sort of like in 2d painting apps, you can have vector or raster graphics. The math is different but the end result is you color some pixels on the screen.
Same idea with nurbs or polygonal surface.
"I have trouble with the terminology. The term "geometry" appears very often in various videos/articles/documentation, but nowhere is it clearly stated what they mean by it. I've looked up the definition in various software glossaries, just browsed the Internet, looked in various dictionaries, but haven't found a satisfyingly clear answer. It seems to be something obvious to everyone."
Its' just a generic - non specific phrase used to describe either a shape or object, usually represented by a series of connected points in 3D space which is widely understood together with other modeling terms, for a very long time.
yeah just a generic term that gets banded about like mesh or object or with nurbs calling them surfaces etc.... in maxscript there is a selection group called $geometry (objects that are renderable) which is a subset of $objects . In the sdk all renderables are derived from the the class GeomObject, though in meshes geometry is the vertices and topology would be the edges and faces :)