Learn 3D Modeling in Blender 2.8 (Episode 1 – Polygons and Primitives)
Have you ever been inspired looking at the cool 3d imageries from Pixar movies or mind-blowing VFX from Hollywood movies? If yes, then I welcome to understand the foundations on which 3D artists all over the world make these amazing graphics. That being said we need to understand the underlying fact that 3D is vast. Big Studios like Pixar have hundreds of people working for them and every top talent among them focuses on one specific task. And on top of that, they have world-class resources available at their service.
I am mentioning this only to provide you an idea of how big the 3D industry is and how it is there to learn.
That being said, everyone has to start somewhere and I hope this post will help understand the basics of 3D art. 3D Pipeline consists of many tasks such as modeling, texturing, rigging, animation, rendering, color grading, and so on. The one we are talking about today is modeling, which is the fundamentals aspect of 3D – nothing happens without modeling. In order to travel further down the pipeline, you need to have a well-working model with you.
Models are basically objects you have within your scene. Let’s say you are making an interior scene of the house. For that, you need to have models like tables, beds, plates, book racks – basically whatever lies within your house, including the house itself. Everything that’s inside the 3D art is the model. In order to start creating models, you need to have a deep understanding of how it’s formed. 3D software like Blender form models with the help of polygons.
What is Polygon?
Wikipedia defines polygon in this way:
Polygons are basically shapes that are connected via vertices using what’s called edges. The basics shapes that we learned during our childhood – most of them are polygons. Triangles, Rectangles, Pentagons, etc. are polygons. 3D Model is the complex product of the polygons that make up the shape we see. The specialty of the polygon is that polygons exist on a well-defined plane. If we connect two vertices together, then that makes up the line, the fact is we do not know the plane of the line because we do not have enough information. However, once we join 3 or more vertices together, then we have well-defined plane. These planes become much more relevant when creating 3D models. Although we are working on 3D, our computer is 2D, right? Hence the 3d image that we work on is the projection of the 3d model. But, as a 3d artist, all we need to understand is that polygons make up the 3D model.
Polygons are a super important topic to understand in 3D. Look at the rectangle, when we combine 2 triangles, it becomes a rectangle, right? A polygon can have either 3 or more vertices connected using edges. When we have 5 or vertices connected together, we call it n-gons. Ideally, we want to work with rectangles (or squares for that matter). The basic idea is to avoid n-gons and the triangle for modeling.
Here’s the thing:
When we create the model, most probably we need to animate it as well. Among all these shapes, only rectangles, and squares deform in a proper manner. We should definitely not need to know why it happens, all we need to know is the basic idea that is to use rectangles in most of our cases. This will probably come with practice – after spending quite some time in 3D animation, your intuition will say when to use n-gons (if that’s necessary)
What are primitives?
In geometry, primitives refer to objects which you can use to create other objects or shapes. Here’s the idea – while modeling you start with the primitive that closely resembles the shape that you’re making. For example, if you are creating a well – then it makes sense to start with a cylinder because that’s what it looks like in a close manner. Of course, real-world modeling looks a bit different. The basics always remain the same – you need to start with the primitive and then work on that. For example, human face closely resembles sphere, hence we start with sphere and tweak that in whatever we can to make it look like a face.
As I mentioned earlier, we do not just want it to look like the shape, we also want to make it functional so that there’s no problem in animating it later. For that, we need a good topology (more on this later).
Here are the few primitives that we use most of the time:
In Blender, there are few more primitives that we use. Here are a few of those: (a model is sometimes referred to as a mesh. The mesh is technically is a collection of polygons, since modeling is just the right arrangement of the polygons, it makes sense to refer to a model as a mesh.)
Let’s take this house as an instance.
This is mostly just a cube and plane. The wooden beams that I used are the cubes. The roofs, the walls, the door, and the window is just the plane. Of course, I have painted it using textures (texturing comes after modeling). Here are the objects or the sub-models that I used in order to create this model:
As a modeler, you need to develop an eye to watch how objects form and probably what’s the best way to get the job done. If you want to make a car, then you generally start with a cube – that’s because the body the car mostly resembles the cube. After that, you will use many modeling tools like extrude, bevel, and subdivide to create a car itself. Now important thing to note here is that model is a shape and not the final step. Sometimes, you may not your model to look like 100% the way you want you final product to look like – texturing can play a role in that. But the general rule is to work on it in a detailed manner so that other steps become quite easy.
In the next tutorial, we’ll discuss the modeling basics like translate, rotate, and scale and discuss vertices, edges, and face and how we can manipulate them.
Assignment: Study about the polygons as much as you can, learn about the vertex, edge, and scale (that will be a lot helpful in the next post).