All you need to know about 3D file formats
Which 3D file formats are there? How do they compare? What should you use? We simply explain the most common 3D file formats used today: STL, OBJ, FBX, COLLADA, 3DS, IGES; STEP, and VRML/X3D.
A 3D file format is used for storing information about 3D models. You may have heard of the most popular formats STL, OBJ, FBX, COLLADA etc. They are widely used in 3D printing, video games, movies, architecture, academia, medicine, engineering, and earth sciences. Each industry has its own popular 3D file formats for historical and practical reasons. We will learn about 3D file formats and take a deep dive into the 8 most common 3D file formats in this article.
What is a 3D File Format?
The basic purpose of a 3D file format is to store information about 3D models as plain text or binary data. In particular, they encode the 3D model’s geometry, appearance, scene, and animations.
The geometry of a model describes its shape. By appearance, we mean colors, textures, material type etc. The scene of a 3D model includes the position of light sources, cameras, and peripheral objects. Finally, animation defines how a 3D model moves.
However, not all 3D file formats store all of this data. 3D file formats such as STL store only the 3D model’s geometry and ignores all other attributes. On the other hand, the format COLLADA stores everything.
STL and COLLADA are just two of the many 3D file formats that people use. We estimate that there are hundreds of 3D file formats currently being used in the wild!
How Many 3D File Formats are there?
The problem with 3D file formats is that there are literally hundreds of them. Every CAD software manufacturer such as AutoDesk and Blender has their own proprietary format which is optimized for their software. So if you use AutoCAD, you get a DWG file. If you use Blender, you get a BLEND file.
Proprietary 3D File Formats Hinder Interoperability
However, the presence of so many proprietary file formats is a big problem. Suppose you use AutoCAD (which is an AutoDesk product) and your friend uses Blender. Suppose that you also want to share your 3D model with your friend.
This is not so easy. Your AutoCAD software gives you a DWG file because it is the native AutoCAD format. But your friend’s software, Blender, can only work with a BLEND file. This means that the two of you cannot work on the same 3D model.
Neutral 3D File Formats Solve this Problem
To solve the problem of interoperability, neutral or open source formats were invented as intermediate formats for converting between two proprietary formats. Naturally, these formats have become hugely popular now.
Two famous examples of neutral formats are STL (with a .STL extension) and COLLADA (with a .DAE extension). They are widely used to share models across CAD software. If you want to share your 3D model, you convert the DWG file to a COLLADA file in a process called exporting and give your friend the COLLADA file. Your friend takes the COLLADA file and imports it into Blender, where the COLLADA file is converted to the native BLEND format. This way, you can continue to use different software and collaborate with others.
Proprietary vs. neutral is one of the most important dichotomies in the world of 3D file formats. Nowadays, most 3D modeling software supports reading and writing popular neutral formats. In addition, most software also support reading and writing to a subset of proprietary formats that are so popular that they cannot be ignored. We will discuss 8 such 3D file formats in this article. Here is the list, where the 3D file formats are marked with their type.
3D file format — Type
STL — Neutral
OBJ — ASCII variant is neutral, binary variant is proprietary
FBX — Proprietary
COLLADA — Neutral
3DS — Proprietary
IGES — Neutral
STEP — Neutral
VRML/X3D — Neutral
But before we discuss each these formats in detail, we will first take a look at the general features of a 3D file format and discuss the important things you should keep in mind when selecting a format for your project.
Alternate Titles
“Know Most Common 3D File Formats”, “Most Used 3D File Formats”, “Understand 3D File Formats”, “List All 3D File Formats”.
Dipesious Research Initiative
Dipesh Bhoir | Maharashtra, IN.
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- Email: dipeshbhoir@hotmail.com
