[FEATURE] Decouple FEM render geometry from sim geometry (multi-sub-mesh + double-sided normal pass)#2904
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[FEATURE] Decouple FEM render geometry from sim geometry (multi-sub-mesh + double-sided normal pass)#2904ACMLCZH wants to merge 7 commits into
ACMLCZH wants to merge 7 commits into
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Introduce a `render_meshes` + `sim_vert_maps` model on FEMEntity so the visualizer can draw the user's original input surface (multi-sub-mesh GLBs supported) while the FEM solver retains its own tet-boundary topology for physics. Changes: - FEMEntity.sample() builds `_render_meshes` (list[gs.Mesh]) and `_sim_vert_maps` (list[np.ndarray]) via `gs.Mesh.from_morph_surface` and a new `_merge_elements` helper that dedupes vertices across sub-meshes and remaps element indices. - FEM solver drops the `surface_render_f` (triangle-indices) and `surface_render_uvs` (per-vertex UV) fields; rendering topology / UVs now live on FEMEntity's per-sub-mesh `Mesh` objects. - `get_state_render(f)` returns sim vertex positions only. - Rasterizer + raytracer iterate per-sub-mesh and key static nodes by `(env_idx, entity.uid, sub_idx)`. - `mesh_to_elements` signature change: accepts a trimesh directly, returns (verts, elems) only (UVs come from the input render mesh). - `gs.Mesh.from_morph_surface` returns a list for primitive morphs too — uniform return type makes consumers simpler. - `test_interior_tetrahedralized_vertex` updated to assert the new invariant: viz vertices = sim_verts[sim_vert_maps[0]].
…-world into pr/fem-render-meshes
duburcqa
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duburcqa
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| def mesh_to_elements(mesh, tet_cfg=dict()): | ||
| tet_file_path = mu.get_tet_path(mesh.vertices, mesh.faces, tet_cfg) | ||
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| # loading pre-computed cache if available |
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| # Verify that the visualizer mesh's vertices correctly track the FEM sim's | ||
| # surface vertices through `fem.sim_vert_maps`. The visualizer mesh | ||
| # (`render_meshes[0]`) holds the *pre-tet-split* input surface (e.g. 12 box | ||
| # triangles), while `fem.surface_triangles` is computed from the *post-split* | ||
| # tetrahedral elements (with mid-edge Steiner subdivisions). The two meshes | ||
| # differ in granularity *by design* — so comparing triangle sets is not the | ||
| # right invariant. The correct invariant is that the renderer's per-vertex | ||
| # buffer updates from `sim_verts[svm]` produce vertex positions consistent | ||
| # with the sim state. |
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…-world into pr/fem-render-meshes
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Summary
Decouple FEM rendering geometry from simulation geometry.
FEMEntitynow carriesrender_meshes: list[gs.Mesh]andsim_vert_maps: list[np.ndarray].sim_vert_mapsis used to map rendering vertices inrender_meshesto simulation vertices fromFEMSolver.FEMEntityalso support segmentation ingeomlevel.[BUG FIX] Support double-sided normal shader for pyrender
Visual
Pair 1 — Ducks (Left Rigid, Right FEM)
Pair 2 — multi-geom FEM rendering (Trashbag_rope.glb)
Before: a uniform user-supplied surface is applied to the whole entity — what the pre-PR solver-side rendering produced (one
entity.surfacefor all sub-meshes). After: each sub-mesh keeps its own GLB material viarender_meshes— the channel's yellow rim is now distinct from the bag body.Snapshots
Genesis-Intelligence/snapshotsupdated →4910d05d2a40de6890263bf92376b389d660d7fb(6 PNGs across 2 commits).tests/utils.py:HUGGINGFACE_SNAPSHOT_REVISIONbumped to match.Next Step
render_meshes.render_meshes.Test plan
pytest tests/test_fem.py— all 6 parametrizes pass against the new render_meshes structure.pytest tests/test_render.py— 64 passed; the multi-sub-mesh FEM render snapshots (rgb/depth/seg/normal) pass via HF revision pin; updatedtest_segmentation_mapformula at"geom"level accounts for per-sub-mesh FEM seg tuples.