trellis_sparse_mrp_mlx/trellis_sparse_mlx/__init__.py
John 93e31f9f80 Sparse DiT blocks for the SLAT flows
SparseDiTAttention / SparseProjectAttention / ModulatedSparseTransformerCrossBlock -
the sparse counterparts of the dense DiT pieces, attending within each batch item.

The modulation needs care: it is per batch item ([B, 6C]) while features are a flat
[N, C] stack, so each row must pick up its own item's shift/scale/gate. Broadcasting
would silently apply item 0's modulation to everything when B == 1.

Verified end to end: slat_flow matches upstream at correlation 1.00000000.
2026-08-02 12:10:31 +10:00

56 lines
2.0 KiB
Python

"""MLX implementation of the TRELLIS-lineage sparse module.
Microsoft's TRELLIS.2 sparse stack has been inherited, near-verbatim, by a growing
family of 3D generation models — LATO.2 and TencentARC's Pixal3D among them. All of
them hard-require spconv or torchsparse, neither of which has a Metal build, and that
single dependency is what keeps the whole lineage off Apple Silicon.
The blocker is one operation: submanifold 3x3x3 convolution. Every SparseConv3d in
these models is constructed `stride=1, padding=None`, which spconv dispatches to
SubMConv3d. Implement that in MLX and the rest is ordinary linear/norm/attention work.
Packaged separately from any one model so each port depends on a tested core rather
than vendoring its own copy.
"""
from .conv import SubMConv3d, build_indice_map
from .dit import (
ProjectAttention,
DiTAttention,
ModulatedTransformerCrossBlock,
MultiHeadRMSNorm,
TimestepEmbedder,
apply_rope,
rope_phases_from_coords,
SparseDiTAttention,
SparseProjectAttention,
ModulatedSparseTransformerCrossBlock,
)
from .tensor import SparseTensor, VarLenTensor, downsample, subdivide, upsample
from .ops import (
LayerNorm32,
SparseFeedForwardNet,
SparseGELU,
SparseGroupNorm32,
SparseLinear,
SparseMultiHeadAttention,
SparseResBlock,
SparseSiLU,
SparseTransformerBlock,
SparseTransformerCrossBlock,
)
__all__ = [
"SparseTensor", "VarLenTensor", "subdivide", "downsample", "upsample",
"SubMConv3d", "build_indice_map",
"SparseLinear", "LayerNorm32", "SparseGroupNorm32", "SparseSiLU", "SparseGELU",
"SparseResBlock", "SparseFeedForwardNet", "SparseMultiHeadAttention",
"SparseTransformerBlock", "SparseTransformerCrossBlock",
# DiT / flow-model pieces
"MultiHeadRMSNorm", "apply_rope", "rope_phases_from_coords", "TimestepEmbedder", "DiTAttention",
"ModulatedTransformerCrossBlock", "ProjectAttention",
"SparseDiTAttention", "SparseProjectAttention",
"ModulatedSparseTransformerCrossBlock",
]
__version__ = "0.1.0"