Table of contents
1.
Introduction
2.
What is the Process of 3D Modeling?
3.
3D file formats
4.
Proprietary 3D file formats
4.1.
Neutral 3D file formats
5.
Common 3D file formats
5.1.
gLTF/GLB
5.2.
FBX
5.3.
OBJ
5.4.
COLLADE
6.
Which 3D file format to choose
7.
High-Poly Models vs Low-Poly Models
8.
Static and Motion Usage
9.
The Complexity of the Geometry
10.
Detalization
11.
Frequently Asked Questions
11.1.
What is augmented reality?
11.2.
How is AR different from VR?
11.3.
What are the examples of AR applications in real life?
12.
Conclusion
Last Updated: Mar 27, 2024
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3D Assets and modeling

Author Ayush Tiwari
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Introduction

3D modeling is a computer graphics approach for creating a three-dimensional digital representation of any item or surface. An artist manipulates points in virtual space (called vertices) with specific software to create a mesh: a collection of vertices that form an item. By deforming the mesh or by modifying vertices, these 3D objects may be constructed automatically or manually.

Video games, film, architecture, art, engineering, and commercial advertising are all examples of where 3D models are employed.

Character animation and special effects need the use of the 3D modeling process, which creates a digital entity that can be completely animated.

The mesh, which is best characterized as a collection of points in space, is at the heart of a model.

What is the Process of 3D Modeling?

An artist usually starts by creating a primitive, such as a cube, sphere, or plane. The primitive is only a beginning point for modeling.

The artist will extend and manipulate this basic form with numerous modeling tools. It's generally always a good idea to start small and work your way up in 3D modeling.

 

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3D modeling is a precise process that often necessitates the meticulous placement of individual vertices to acquire the target object's right shapes.

Polygons make up the mesh's exterior, which can be dissected into smaller shapes to add more complexity. If the 3D model is to be animated, these subdivisions are extremely important.

These additional polygons will be required for any joints that must bend, such as a character's knee or elbow.

There are several tools available to help speed up the modeling process. Most applications feature a mirroring technique that allows the artist to create a symmetrical model by merely working on half of the object—or even a quarter of it.

3D file formats

Simply put, a 3D file format is a file format that holds data about 3D models. Geometry (its shape), look (its color, texture, and/or materials), scene (the location of a light source, camera, or other objects around the 3D model), and animations are all examples of this (how the 3D object moves, including skeletal information and morphs).

The 3D information is stored in 3D models as either plain text or binary data.

Because each 3D software package has its own file format that is suited for that software, there are literally hundreds of 3D file types accessible. Blender, for instance, has BLEND, AutoCAD has DWG, Clo has .zprj, and Browzwear has .bw, to mention a few.

With hundreds of 3D file formats to choose from, it's difficult to know which one to use or how it compares to others. We've highlighted the greatest 3D file formats for 3D online and AR, as well as their best use cases, to remove the guessing out of 3D file formats.

Proprietary 3D file formats

The issue with proprietary 3D file formats is that practically all of them are proprietary, which means they can't be read by other programmes.

Assume you're working using Blender and your 3D fashion designer colleague is working with Browzwear. You have a 3D model that you need to share with a colleague, but you can't work on it together because you're working with separate proprietary 3D file formats. Blend is not compatible with Browzwear and. Blender will not accept bw files.

What is the answer? FBX or neutral 3D file formats While FBX is a proprietary format, it is widely used as an exchange format by numerous software products.

Neutral 3D file formats

Neutral (or open source) 3D file formats were created to address the issue of interoperability. These nonproprietary formats act as a bridge between two proprietary formats.

As you may expect, designers and 3D artists are big fans of these neutral formats. If you want to share your 3D model with a colleague who isn't using the same 3D design programme as you, you may convert it to a neutral 3D file format and send it to them to import into their programme. If you export an FBX from Browzwear, for example, you can import it into Blender. You can continue to utilise various software while communicating with others with minimal effort.

Common 3D file formats

Most 3D modelling software platforms now handle neutral 3D formats, but converting a 3D file too many times might cause problems. To avoid unwanted conversions, you must still choose the appropriate neutral 3d format from the start.

Here are the eight most prevalent 3D file formats and why they should be on your radar to help you pick the appropriate 3D format for your purposes.

gLTF/GLB

gLTF/GLB is an open source, neutral format. This format was established by the Khronos Group for 3D online, AR, VR, games, and 3D advertising. It is the first truly well-defined 3D standard. Geometry, materials, textures, colours, and animations are all supported by this file format. This incorporates PBR (Physical Based Rendering), which improves the realism of shadows and light.

Because gLTF is built on JSON, some data, such as textures (JPEG or PNG), shaders (GLSL), and geometry and animation data, is stored in external files (BIN). All of this information is stored internally in GLB files. This file format is always being improved and updated by the Khronos group. It is gradually establishing itself as the industry standard for 3D shopping.

FBX

The FBX file format is a proprietary 3D file format. This format was created by Kardara. In 2006, AutoDesk bought them and continues to support FBX. In the film and video gaming industries, it is commonly used. Geometry, appearance (colour and texture), and animations are all supported (skeletal and morphs). FBX is a popular animation file format that can be exchanged between programmes such as Maya, 3DSMax, AutoCAD, Roman's CAD, and others.

OBJ

When used as an ASCII variation, OBJ is a neutral 3D format. It is, however, proprietary when used as a binary variation. This file format is used in 3D printing, graphics, and 3D scanning since it can store geometry as well as colour and texture information. A separate file with the extension stores colour and texture information in this file format. MTL. Although OBJ does not support animations, it is one of the most used 3D graphics interchange formats.

COLLADE

COLLADE is another neutral 3D file format developed by the Khronos Group. Geometry, appearance, scene, and animations are all stored in this file format. It's also one of the few file formats that can handle physics and kinematics. COLLADE, which was previously widely used, has dwindled in popularity as a result of its inability to keep up with modern technology. Instead of updating this format, the Khronos Group produced the new GLTF format.

Which 3D file format to choose

Before deciding on a 3D file format, we propose that you ask yourself the following questions:

  1. What characteristics do I require? You may require different capabilities in your ideal 3D file format depending on the business you work in.
  2. Which software will I employ? Because not all software supports importing and exporting of all 3D file types, you must select one that does.
  3. My collaborators use which software? The file format you select must be compatible with both your projects and those of your collaborators.
  4. What is the 3D file's intended use? GLB/GLTF and USDZ/USD, for example, are required for 3D online or AR experiences.

 

There is two main types of 3D model.

  1. High-Poly Models
  2. Low-Poly Models

High-Poly Models vs Low-Poly Models

Instead of prototypes and old-school photography, producers and marketers now have a plethora of new product promotion options thanks to 3D modelling. 3D models can be utilised for any CG service, including static rendering, 3D configurators, animation, and even interactive VR/AR applications, as you can see. The sole distinction is that high-poly models are required for some activities while low-poly models are required for others.

Thankfully, a multidisciplinary 3D modelling firm can produce any type of 3D model rapidly and save it in universal 3D formats such as obj, max, fbx, blend, mtl, and others. Client managers are also available 24/7 to answer questions about CG services and assist clients in selecting the appropriate modelling type.

So, what exactly are low-poly and high-poly models, and how do they differ? Both words are derived from polygon modelling, which is the process of creating 3D models using polygons. These are little closed geometric shapes that are merged into a single mesh that serves as a 3D object's surface. As a result, high-poly models have a lot of polygons, whereas low-poly models have fewer.

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Static and Motion Usage

Let's start with 3D model application because its structure is directly dependent on it. High-poly models, in particular, are ideal for static HR renders such as lifestyle shots, silo renders, close-ups, and cut-outs, as well as featured animation with a zoom effect. Because these are high-quality CGI, such models should be extremely detailed and precisely created.

Low-poly CG imagery is utilised for interactive 360° views, 3D configurators, games, and AR/VR imaging. These models must be compatible with rendering and gaming software. As a result, they should just have a few polygons so that any software can process them quickly.

The Complexity of the Geometry

The geometry of high-poly models is quite complex, as it is made up of numerous polygons of various shapes, especially when it comes to curved things. In this situation, CG artists meticulously construct the geometry and double-check it to avoid high-poly modelling problems such as chipping, obvious seams, holes in the surface, and so on.

Low-poly models are geometrically simpler and include fewer polygons. Because of this quality, 3D objects can be used in apps and on any digital platform. Retopology is used by 3D modelers to further improve the geometry.

Simply explained, 3d Max retopology is the process of lowering the number of polygons in a mesh. Thousands of polygons, or vertices and faces that comprise a mesh, make up the average-sized 3D object. This makes texturing and rendering without defects challenging. Retopology smoothes and lightens 3D models, allowing them to be rendered quickly while maintaining great visual quality.

Detalization

High-poly models can be thoroughly detailed with various decorations, additional decor, sophisticated design components, and so on, thanks to superior geometry. Naturally, a 3D model like this appears more realistic, and hence stunning. Complex 3D models for your furniture with inlay, forging, carvings, and other features require meticulous detailing. Even with high-poly 3D models for static CGI, CG specialists always undertake retopology with such complicated objects.

Low-poly objects, on the other hand, cannot be hyper-detailed. If your furniture has a lot of intricacies and fittings, yet you need it for a 360° view or a 3D configurator, CG artists will have to retopologize it. Otherwise, they'll be too big for the engine to render in real time.

Frequently Asked Questions

What is augmented reality?

Augmented reality (AR) augments your surroundings by adding digital elements to a live view. It is often done by using a camera on a smartphone.

How is AR different from VR?

AR uses a real-world setting while VR is entirely virtual. 

What are the examples of AR applications in real life?

Snapchat, Google street view, Pokemon Go, and Microsoft Hololens are some of the examples of AR applications in real life.

Conclusion

I hope this blog helped you provide some meaningful insights on about various 3D modeling technique that is influencing and impacting the AR industry.

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