3D modelling is a highly technical skill that we are lucky to be able to utilise at Stada Media. A 3D model used for animation or visualisation can create an incredibly immersive experience of a product that is otherwise difficult to represent appealingly to customers.
Read our blog post on how using 3D animation can greatly improve your marketing here.
In this post we’ll take you through the basics of 3D modelling and the usual process when creating a 3D model for a client.
When thinking about the process of 3D modelling, we’ll first quickly talk about what 3D modelling is and what types are out there.
What is 3D modelling?
3D modelling is the process of developing a mathematical representation of a 3D surface or object using specialised software.
(3D models can also be physically created through 3D printing, but this post will primarily focus on 3D modelling for use in video.)
Types of 3D modelling
There are two main types of 3D modelling: CAD modelling and 3D modelling.
CAD modelling
CAD modelling is used in engineering and its end use is physical products. This is where 3D printing would feature.
3D modelling
3D modelling is used primarily for creative purposes and it has virtual end uses – think film, video games, video, etc.
Key terms
Check out this infographic for all the key terms you need to know in 3D modelling:
Solid 3D model = A 3D model that defines the volume of the object it represents. More realistic, but harder to build.
Shell or Boundary 3D model = A ‘hollow’ 3D model that represents the surface of the object, not the volume.
CGI = Computer Generated Imagery
Axis = X, Y, Z coordinates of the 3D space
Point = A one-dimensional point in the 3D space
Polygon = A 2D shape with 3 sides or more
Grey render = A preview render without textures
Mesh = The surface (geometry) of a 3D model
NURBS/Spline = A 2D curve or path
Texture = An image applied to the 3D model
Lighting = Placing lights in the scene
Rendering = Converting the 3D data into an image
Rigging = Setting a character up in order to animate it
Wireframe = A way of viewing the model as lines, outlining the mesh
Subdivide/subdivision = Dividing the polygons within a mesh
Although there are two main types of 3D modelling, we use shell or boundary modelling at Stada Media, so we will be focusing on this in this post.
3D modelling processes
Just as there are different types of 3D models, there are also different ways to create a 3D model.
Hard surface models
Polygonal modelling or Box modelling: The simplest form of modelling. It’s best suited to forming regular ‘hard edge’ objects or products. However, it’s not suitable for curved objects as the mesh is often needed to be subdivided to form the smooth curve.
NURBS modelling: NURBS modelling is using splines (as defined in the infographic above) to create the geometry of an object. It’s most suited to curved surfaces.
Photogrammetry: Using photographic images or ‘scans’ to create a 3D object.
Organic models
Sculpting: Sculpting is used to create highly detailed, organic (natural) models such as trees, rocks, etc. It’s much more time consuming than hard surface model processes, and is relatively specialised.
Texturing and lighting
After the basic 3D object has been created, it needs texture and light to make it into the realistic model you see in the finished product.
At this stage, it becomes clear why a 3D model is able to look so similar to its real-world counterpart.
This is because the processes involved aim to imitate how light and texture behaves in the real world.
First, to achieve texture, various mapping techniques are used. After that you need to add lighting.
Mapping techniques to create texture
Cubic mapping: Cubic mapping uses the 6 faces of a cube as the map shape.
Projection mapping: Projection mapping projects the 2D image of the texture onto the 3D object from a virtual camera.
UV mapping: Unwrapping the U and V (X, Y & Z) coordinates of the object as a 2D plane that is mapped to the surface. UV mapping is often more time-consuming, so keep this in mind when thinking about the turnaround time for your project.
Lighting
Point lights emit rays from a single point.
Spot lights emit rays from a single point in a cone.
Directional lights emit rays in a parallel or linear direction to the whole scene.
Area lights emit rays from a plane or surface.
After texture and lighting, and approval from your client, you are ready to render your 3D model.
Rendering
As explained in the above infographic, rendering is the process of converting the 3D data into an image.
Rendering softwares are usually stand-alone programmes that we often refer to as render engines.
Rendering mainly works via a process known as ray tracing.
Ray tracing replicates the way light behaves by firing rays at the 3D object.
Ray tracing is often used in conjunction with Global Illumination (GI).
Global Illumination mimics the way light bounces to create more realistic lighting within the render.
Now you know the techniques involved in creating a 3D model, but what about creating a 3D model as part of a client project?
Overview of a typical 3D project
1. You discuss the client project with both the client and your team to determine a turnaround time.
2. You receive the client brief along with any assets you may need – usually CAD models or drawings. Then check these over to ensure they can be opened and used.
3. The modelling process begins. This stage usually involves cleaning up the topology of the CAD models.
4. You send the model to your client as a grey render to check the model’s geometry is correct.
5. If you only have a short turnaround time, the textures are applied now.
6. You receive the first round of amends for the model.
7. Once the amends are approved, you rig and/or animate the animated elements of the model.
8. You then render the animation out again as a grey render and send to your client for approval.
9. The model gets more amends.
10. Next, you apply your textures to the model. Stills of it are then sent to the client.
11. Amends – again!
12. Hopefully, you will now be able to start the final animation, or full-resolution renders of stills.
13. Once the rendering is complete, you send the finished product to your client.
14. Pray for no more amends!
In this post we’ve given you a full look into how we create 3D animations and visualisations for clients.
It can be a tricky and lengthy process, but luckily we have the talent in-house to overcome any challenges and come out the other side with a fantastic 3D creation exploding with WOW!
Interested in our 3D services? Let’s talk today about what we could do for you.
If you want more insight into video production, have a gander at our other blog posts right here!
