Open-Source Big Fat Fish 3D Model: An Unfinished Interactive Experiment

A Bilibili content creator encountered technical bottlenecks while attempting to create a "Big Fat Fish" 3D model and ultimately chose to open-source the model to a group file. Behind this seemingly simple share lies the typical challenges individual developers face in 3D modeling and interactive application development.

Original Intent: Let the Big Fat Fish Live in Your Phone

The creator's idea was quite playful: build a 3D version of "Big Fat Fish," put it in a mobile app, and let users interact with it—feed it white rice, or even give it an old phone so it can "play on a phone." This essentially combines a virtual pet with concrete operations, exploring a new form of interaction. According to the creator, the initial goal was to "finish it and put it in the software as a fun little development," and thereby share it with more people.

This idea reflects the creator's pursuit of emotional design: by giving a digital character life-like behaviors (eating, playing on a phone), it narrows the distance between technology and users. However, from idea to implementation, there is a technical gap.

Technical Bottlenecks: The Dual Challenge of Modeling and Rigging

The creator admitted, "I'm not very good at making wasabi" (here "wasabi" is likely a homophone or slip of the tongue for "modeling"), and "the thing I poked out is also weird." This points to two specific problems: first, the model's structure itself is unreasonable; second, action rigging is difficult. For a 3D character to achieve natural interaction, it needs not only a fine mesh but also skeletal rigging and an animation system. For non-professional developers, the learning curve for these steps is steep.

From the screenshot, the creator clearly encountered obstacles when trying to adjust the model. This "weird" feeling often stems from disproportionate proportions or poor topology, which makes subsequent rigging and animation difficult.

Skeletal rigging and skinning are the core technologies of 3D character animation. Skeletal rigging refers to building a virtual skeleton (joint hierarchy) inside the model and assigning model vertices to each bone by weight; skinning makes the mesh deform as the bones move. Rigging quality directly determines the naturalness of the animation: uneven weight distribution can cause the mesh to tear or collapse at the joints. For non-professional developers, common tools such as Blender's automatic weights can quickly generate basic rigs, but complex characters still require manual adjustment. In addition, topology (the distribution of mesh vertices and edge flow) is also crucial—reasonable topology simplifies rigging and supports deformation, while randomly generated meshes often have chaotic edge flow at the joints, causing strange distortions during animation. This is the deeper reason the creator felt the model was "weird."

Turning to 2D and the Decision to Open-Source

Faced with the high threshold of 3D, the creator decided to turn to 2D and continue exploring. The completed 3D model was placed in a group file for anyone who needed it. This choice is both a pragmatic assessment of their own abilities and a reflection of the spirit of open-source sharing—even if unfinished, the model itself still has reference value.

Open-source 3D models are not uncommon in individual development, but they usually come with incomplete or non-standardized issues. The creator did not specify the model format or license agreement, which may limit its reuse. However, for learners and enthusiasts, such resources can still serve as practice material.

Common formats and licenses for open-source 3D models deserve attention. Common formats include FBX (supports bones and animation, compatible with most game engines), GLTF/GLB (web-friendly, gradually becoming a standard), OBJ (static mesh only), and others. If the format is not specified, users must convert it themselves, which may lose rigging information. Regarding licensing, open-source licenses such as Creative Commons (e.g., CC BY, CC BY-SA) or MIT can clarify reuse rights; if not declared, all rights are reserved by default, making it difficult for others to use legally. For learning purposes, even an incomplete model can be imported into tools such as Blender to observe its topology and rigging setup, serving as a negative example or practice material. Therefore, including format descriptions and license declarations when open-sourcing can significantly improve the usability of the resource.

Lessons for Individual Developers

This attempt reveals several key points: first, 3D interactive application development requires interdisciplinary knowledge (modeling, rigging, programming), and individual developers can easily get stuck at one step; second, rapid prototype validation is important—after discovering the difficulty of the 3D route, the creator promptly switched to 2D, avoiding greater investment; third, community sharing can reduce duplicated work, and even imperfect models may help others.

From a broader perspective, playful projects like "Big Fat Fish" are valuable not only for the final product but also for the exploration process. Although the creator's share is brief, it truly reflects the trial and adjustment in independent development. For readers who want to try similar projects, it is recommended to start with 2D or simple 3D prototypes, gradually master the basics of rigging and animation, and then consider complex interaction.

Conclusion

The open-sourcing of the "Big Fat Fish" 3D model is an honest share of an unfinished experiment. It reminds us that bringing ideas to life requires technical support, and the open-source community is an important way to fill gaps in individual capabilities. Perhaps in the future, the creator's 2D version will bring a more complete interactive experience.

One-line Summary

A Bilibili creator, lacking 3D modeling and rigging skills, open-sourced the unfinished Big Fat Fish model and turned to 2D development.

Paragraph Summary

A Bilibili creator planned to make a 3D "Big Fat Fish" model and put it in a mobile app for feeding and other interactions, but was hindered by insufficient modeling and skeletal rigging skills. Unreasonable model structure and rigging difficulties led to a "weird" result. The creator ultimately turned to 2D and open-sourced the completed 3D model to a group file for others to use. This case reflects the multidisciplinary barriers individual developers face in 3D interactive application development and also demonstrates the value of rapid prototype validation and community sharing. The article suggests similar projects start with 2D or simple 3D prototypes and gradually master the basics of rigging and animation.