zephyr

Results 4 issues of zephyr

Changes: * Do triplane sampling in a block based manner, reduced VRAM usage. This version can generate 1024^3 on 3090 in 33 seconds, use only 13GB VRAM. Actually this version...

I set marching cubes resolution to highest(320), there is significant jagged edges. ![2024-03-18 222250](https://github.com/VAST-AI-Research/TripoSR/assets/6714068/42010b45-de31-42e5-88b7-3249a3dd12f1) The model outputs density fields, I think using distance field will get better mesh quality?

I think the compiler need to be customizable.

### Your current environment ```text PyTorch version: 2.3.0+cu121 Is debug build: False CUDA used to build PyTorch: 12.1 ROCM used to build PyTorch: N/A OS: Ubuntu 22.04.3 LTS (x86_64) GCC...

bug