KhronosGroup
Implement Draco Encoding Compression algorithm
Hi all! I would like to implement the draco compression algorithm on my own for creating gltf/glb files, but it is not clear to me what is the algorithm to implement.
I found this docs: https://observablehq.com/@mourner/edgebreaker-the-heart-of-google-draco [https://faculty.cc.gatech.edu/~jarek/papers/EdgeBreaker.pdf](url)
But it is still not clear to me how I could start, do you have any suggestion on this? Any help would be much appreciated
Thank you in advance
The draco extension page has links to the official resources https://github.com/KhronosGroup/glTF/blob/main/extensions/2.0/Khronos/KHR_draco_mesh_compression
I think it's fair to say that only one implementation of the Draco encoder currently exists, and that encoder is integrated (as C/C++ or WASM) into many glTF creation tools. While there should be enough detail in the specification and linked resources to implement it from scratch, be warned that it's a large undertaking. Implementing a decoder from scratch might be more practical, if that's sufficient for your needs.
If you're OK with using the official Draco encoder in your own glTF/GLB creation pipeline, you can see how I implemented Draco encoding in my own tool, glTF Transform, below. The encoder.ts file contains most of the code you'll need:
- https://github.com/donmccurdy/glTF-Transform/tree/main/packages/extensions/src/khr-draco-mesh-compression
Thank you guys! Yes I understand that rewriting the encoder is a big job, let's say that I am interested in how the algorithm works other than reduce the size of geometry and implement it in a custom converter directly, but I didn't find the algorithm or the pseudo code, this is why I created the issue.
If you guys will find something about it, please tell me 😀
BTW I will consider using the official Draco encoder in my pipeline.
Here is the specification for the bitstream and decoder:
https://google.github.io/draco/spec/
I believe the exact implementation of an encoder is open to interpretation and not intended to be standardized, as long as the bitstream itself follows the specification.
There is a reimplementation from MPEG with more details description. Maybe you can take a look.
