Coin3D: Controllable and Interactive 3D Assets Generation with Proxy-Guided Conditioning

Coin3D: Interactive and Controllable 3D Asset Generation

Creating 3D assets has often been a specialized task requiring significant expertise in modeling software. But what if we could simplify this process, making it accessible even to those without advanced skills? That's where Coin3D steps in with a fresh perspective on 3D asset generation.

What is Coin3D?

Coin3D is a framework that allows users to create 3D objects interactively and with ease. It takes the principles of 2D diffusion models used for generating images and adapts them for 3D. Instead of demanding extensive modeling knowledge, users can start with basic shapes—think cubes, spheres, and cylinders—and assemble these into a coarse proxy of the desired object. Then, Coin3D uses this proxy to generate detailed 3D assets.

Key Features of Coin3D

3D-Aware Control with Proxies

At its core, Coin3D uses simple geometric proxies as guides for generating 3D models. These proxies can be anything from a basic stack of shapes to more complex assemblies. Users can create these proxies using familiar tools like Tinkercad or Blender. By voxelizing these shapes and integrating them into a multi-view diffusion process, Coin3D can generate detailed 3D objects that closely follow the intended design.

Here's how the process works:

1. Input Creation: Users create a proxy using basic shapes and add corresponding text prompts.
2. Feature Extraction: The proxy is voxelized into a feature volume that guides the 3D generation.
3. Diffusion Process: This volume integrates with a multi-view diffusion model to produce consistent images from different angles, ensuring that all views of the 3D object are coherent.

Interactive and Responsive Generation

One of the standout features of Coin3D is its interactive workflow. Users can not only generate entire models but also make fine-grained edits to specific parts. For example, you could start with a basic model of a car and then interactively add or modify parts like wheels or mirrors without needing to redo the whole model. This involves:

• Proxy-Bounded Part Editing: Users can designate and edit specific parts of the proxy. The system ensures that only the selected parts are updated, while the rest remains consistent.
• Progressive Volume Caching: To enable quick previews from any angle, Coin3D caches the volumetric information. This means users can see the results of their edits almost instantly, making the modeling process much more intuitive.

Consistent 3D Reconstruction

Generating images from multiple angles is one thing, but ensuring these images translate into a consistent 3D model is another challenge. Coin3D addresses this with a volume-conditioned reconstruction strategy. By leveraging the 3D control volume during the reconstruction phase, Coin3D provides high-fidelity 3D models suitable for further use in computer graphics applications.

Performance and Comparisons

In terms of results, Coin3D demonstrates robust performance. The authors of the paper evaluated Coin3D against some existing methods like Wonder3D and SyncDreamer. The key metrics for evaluation included:

• CLIP Score: Measuring how well the generated object matches the text description.
• ImageReward and GPTEvals3D: Assessing the perceptual quality of the generated views.
• User Studies: Collecting feedback on user satisfaction with the generated models.

Across these metrics, Coin3D consistently showed better performance, particularly in how closely the generated objects matched the provided proxies and descriptions. This suggests that the 3D-aware control significantly enhances the quality and usability of generated models.

Implications

The implications of Coin3D extend beyond simply making 3D modeling easier. By providing an accessible way to create and edit 3D models interactively, Coin3D could democratize 3D content creation. This means more artists, designers, and even hobbyists could start creating high-quality 3D assets without needing deep expertise in 3D software.

Future Directions

While Coin3D already shows significant promise, there are clear paths for future enhancement:

• Broader Shape Library: Expanding the basic shapes available for proxies could make the system even more versatile.
• Real-Time Collaboration: Integrating real-time collaborative features could further enhance its utility for team-based projects.
• Advanced Editing Tools: Adding more sophisticated editing capabilities, such as texture manipulation or physics-based simulation, could push the boundaries of what users can create.

In essence, Coin3D represents a significant step forward in making 3D modeling more intuitive, interactive, and accessible to a wider audience. By leveraging both 3D-aware control and responsive workflows, it paves the way for a future where anyone can bring their 3D ideas to life with ease.