Introduction
The world of 3D graphics has revolutionized the way we interact with digital content, providing immersive, lifelike experiences right in our web browsers. With libraries such as Three.js, tools like Blender, and various 3D file formats, we can create captivating and interactive 3D environments and models.
This chapter aims to give you an overview of these topics, along with a lexicon of key 3D terminology.
Introduction to Three.js
Three.js is a popular JavaScript library that simplifies the process of working with 3D graphics on the web. It provides an easy-to-use API for creating and manipulating 3D objects, handling 3D animations, loading 3D models, and more. Three.js sits atop WebGL, a JavaScript API for rendering 2D and 3D graphics in a web browser without the use of plug-ins.
To use Three.js, you'll need a basic understanding of JavaScript. Once you have that, you can begin creating scenes, setting up cameras, and creating and manipulating 3D objects — all within your web browser. To learn three I would refer you to Three-js Journey!
Blender: A Powerful 3D Creation Suite
Blender is an open-source 3D creation suite that supports the entirety of the 3D pipeline—modeling, rigging, animation, simulation, rendering, compositing, and motion tracking. It's versatile, robust, and best of all, free. While the learning curve can be steep, the vast community and abundance of tutorials make it an excellent tool to get started with 3D modeling and animation for the web.
Once you've created a 3D model or animation in Blender, you can export it to a web-friendly format (like GLTF or OBJ), and then load it into your web application using Three.js.
Understanding 3D Terminology
When starting with 3D, there are some fundamental terms you should familiarize yourself with:
- Mesh: A mesh is a collection of vertices, edges, and faces that define the shape of a 3D object. It's the "skin" that covers the object you're creating.
- Vertex: In the world of 3D, a vertex is a data structure that describes certain attributes, like the position of a point in 2D or 3D space or multiple points on a surface.
- Face: In 3D modeling, a face refers to the flat or curved surface of a 3D model.
- Edge: An edge is a line segment connecting two vertices in a polygon mesh.
- Baking: Baking is the process of taking information like lighting, textures, or animation, and "baking" it into texture maps or the 3D model itself. This allows complex effects and details to be reproduced efficiently in real-time environments, like a web browser.
Common 3D File Formats: GLTF and OBJ
Once you have created a 3D model in a tool like Blender, you'll need to export it in a format that can be used on the web. Two of the most commonly used formats are GLTF and OBJ.
- GLTF (GL Transmission Format): This is a royalty-free specification for the efficient transmission and loading of 3D scenes and models by applications. GLTF was designed to minimize both the size of 3D assets and the runtime processing needed to unpack and use those assets. It's often referred to as the "JPEG of 3D."
- OBJ (Object File): OBJ is a simple data-format that represents 3D geometry. It's a common export format from many 3D tools like Blender and is widely supported.
These formats allow for a 3D model created in Blender (or other 3D software) to be exported and then used in a Three.js scene.
Remember, the world of 3D for web is vast and constantly evolving. This chapter serves as a fundamental starting point, but there are many more concepts, tools, and techniques to explore as you delve further into the 3D realm.
Key Considerations
It's crucial for producers to understand not just the technicalities of 3D modeling and development, but also the unique challenges, best practices, and considerations in these domains. Let's cover a few of these aspects:
- Complexity and Performance: Remember, every detail added to a 3D model increases its complexity and can impact the model's loading time and performance on the web. 3D models should be as simple as possible without sacrificing the necessary level of detail. This is particularly important for mobile devices, where performance is more constrained.
- Optimization: Part of a 3D artist's job is optimizing a model to look as good as possible while containing the fewest polygons or vertices. The process of reducing the number of polygons in a 3D model is known as 'poly count reduction' or 'mesh simplification.' This process should be kept in mind during the modeling stage.
- Textures: High-resolution textures can make a model look realistic, but they can also significantly increase the load time and negatively impact performance. Texture optimization, which includes techniques such as texture compression, mipmap levels, and baking, is a crucial part of preparing a 3D model for the web.
- Real-Time Rendering: Unlike in pre-rendered 3D graphics, real-time rendering (like in a web browser) has strict performance requirements. Techniques such as baking can be used to pre-compute complex lighting and shading in a texture, reducing the real-time computation required.
The Handover Process from 3D Modelling to Development
For a smooth transition from 3D modeling to development, it's essential to have a clear handover process. Here are some steps to consider:
- Finalizing the Model: Before handing over the model, ensure that it's finalized and optimized. This includes the geometry, textures, and any animations or other features.
- Exporting the Model: The model needs to be exported in a format that's compatible with the web and agreed upon by the 3D artist and the developer. As mentioned, common formats include GLTF and OBJ.
- Documentation: The 3D artist should provide clear documentation about the model, its features, and any specific requirements for implementation. For instance, if a model has animations, there should be clear instructions on how to trigger them.
- Collaboration: Ongoing collaboration between the 3D artist and the developer is crucial. There may be adjustments and iterations needed after the model has been implemented, and maintaining open communication channels can help quickly resolve any issues.
3D for the web involves a balance between aesthetics and performance. While the goal is to create visually appealing and interactive 3D content, it must be done in a way that is optimized for real-time rendering and respects the performance constraints of the user's device.
Exercise
Downloading a free GLTF 3D file from Sketchfab and load it onto a GLTFviewer to test it.
