Reviewing files that changed from the base of the PR and between 3ec30d8 and 47109b9.

• docs/api/_generated/newton.sim.ShapeGeometry.rst is excluded by !**/_generated/**
• docs/api/_generated/newton.sim.ShapeMaterials.rst is excluded by !**/_generated/**

• docs/api/newton_sim.rst (0 hunks)
• newton/__init__.py (0 hunks)
• newton/examples/example_anymal_c_walk_on_sand.py (1 hunks)
• newton/examples/example_mujoco.py (1 hunks)
• newton/examples/example_selection_materials.py (1 hunks)
• newton/sim/__init__.py (0 hunks)
• newton/sim/builder.py (14 hunks)
• newton/sim/collide.py (4 hunks)
• newton/sim/flags.py (1 hunks)
• newton/sim/model.py (2 hunks)
• newton/sim/types.py (0 hunks)
• newton/solvers/euler/kernels.py (6 hunks)
• newton/solvers/featherstone/solver_featherstone.py (1 hunks)
• newton/solvers/mujoco/solver_mujoco.py (5 hunks)
• newton/solvers/style3d/kernels.py (2 hunks)
• newton/solvers/style3d/solver_style3d.py (1 hunks)
• newton/solvers/vbd/solver_vbd.py (8 hunks)
• newton/solvers/xpbd/kernels.py (7 hunks)
• newton/solvers/xpbd/solver_xpbd.py (3 hunks)
• newton/tests/test_import_mjcf.py (1 hunks)
• newton/tests/test_import_urdf.py (2 hunks)
• newton/tests/test_import_usd.py (1 hunks)
• newton/tests/test_model.py (1 hunks)
• newton/tests/test_mujoco_solver.py (4 hunks)
• newton/utils/import_mjcf.py (2 hunks)
• newton/utils/import_urdf.py (2 hunks)
• newton/utils/recorder.py (2 hunks)
• newton/utils/render.py (5 hunks)
• newton/utils/selection.py (1 hunks)

• newton/init.py
• docs/api/newton_sim.rst
• newton/sim/init.py
• newton/sim/types.py

• GitHub Check: Run GPU Unit Tests on AWS EC2 (Pull Request)
• GitHub Check: Run GPU Benchmarks (Pull Request)

newton/utils/selection.py (1)

450-450: LGTM! Comment correctly updated to reflect new attribute naming.

The comment example has been properly updated from the old structured attribute format ("shape_materials.mu") to the new flat array format ("shape_material_mu"), which aligns with the removal of ShapeMaterials structs throughout the codebase.

newton/utils/import_urdf.py (1)

251-251: LGTM! Attribute names correctly updated for consistency.

The changes from builder.shape_geo_type to builder.shape_type are consistent with the broader refactoring that removed the ShapeGeometry structured types and simplified the attribute naming scheme. The functionality remains unchanged - these are still used to track the range of newly added shapes during URDF parsing.

Also applies to: 320-320

newton/sim/flags.py (1)

38-38: LGTM! Docstring enhanced for better clarity.

The expanded docstring properly clarifies that NOTIFY_FLAG_SHAPE_PROPERTIES covers shape transforms, geometry, and material properties. This improvement better reflects the scope of this flag, especially given the refactoring that replaced structured types with individual property arrays.

newton/solvers/style3d/solver_style3d.py (1)

191-191: LGTM! Consistent with material property refactoring.

The change from self.model.shape_materials to self.model.shape_material_mu aligns with the systematic removal of structured types in favor of individual property arrays. This change is consistent with similar updates across other solver modules and the corresponding kernel update in newton/solvers/style3d/kernels.py.

newton/tests/test_import_mjcf.py (1)

113-113: LGTM! Test updated for new attribute naming scheme.

The change from model.shape_geo_src[i] to model.shape_src[i] correctly updates the test to use the new simplified attribute name. The test logic and coverage remain unchanged - it still validates that meshes have the correct maxhullvert values after MJCF parsing.

newton/utils/import_mjcf.py (1)

768-768: LGTM! Attribute renaming aligns with refactoring.

The changes from builder.shape_geo_type to builder.shape_type are consistent with the broader refactoring to remove the ShapeGeometry structured type and flatten shape geometry attributes. The logic for determining shape count ranges for collision filtering remains correct.

Also applies to: 793-793

newton/examples/example_selection_materials.py (1)

205-205: LGTM! Material attribute access updated correctly.

The changes from "shape_materials.mu" to "shape_material_mu" correctly reflect the refactoring from structured ShapeMaterials type to individual material property arrays. The functionality for accessing and setting friction coefficients remains unchanged.

Also applies to: 210-210, 213-214

newton/tests/test_model.py (1)

252-252: LGTM! Test attribute references updated correctly.

The test assertions have been properly updated to use the new attribute names (shape_src, shape_type, shape_scale) instead of the old shape_geo_* prefixed names. This aligns with the refactoring to remove the ShapeGeometry structured type. The test logic and verification remain unchanged.

Also applies to: 256-258, 262-264

newton/utils/recorder.py (1)

183-183: LGTM! Serialization logic correctly updated.

The removal of special handling for ShapeMaterials and ShapeGeometry types in the serialization/deserialization methods is consistent with these structured types being removed from the codebase. The generic serialization logic for other supported types remains intact.

Also applies to: 227-227

newton/tests/test_import_urdf.py (1)

164-165: LGTM! Test assertions updated for new attribute names.

The test assertions have been correctly updated to use the new simplified attribute names (shape_type, shape_scale, shape_src) instead of the old shape_geo_* prefixed names. This maintains test coverage while aligning with the refactoring to remove the ShapeGeometry structured type. The test logic and verification conditions remain unchanged.

Also applies to: 184-185, 187-188, 194-196

newton/solvers/style3d/kernels.py (1)

151-151: LGTM! Consistent parameter type refactoring.

The replacement of ShapeMaterials structured type with shape_material_mu: wp.array(dtype=float) aligns perfectly with the broader refactoring to remove structured material types in favor of individual arrays. The parameter is correctly passed through to evaluate_body_particle_contact on line 181.

Also applies to: 181-181

newton/tests/test_import_usd.py (1)

252-252: LGTM! Test attributes correctly updated.

All attribute renamings follow the consistent pattern of removing the geo infix from shape geometry attributes:

• shape_geo_type → shape_type
• shape_geo_src → shape_src
• shape_geo_scale → shape_scale

The test logic remains unchanged and correctly validates the refactored model structure.

Also applies to: 255-255, 261-261, 265-267, 271-271

newton/examples/example_mujoco.py (1)

107-107: LGTM! Attribute references correctly updated.

All references to articulation_builder.shape_geo_src have been consistently updated to articulation_builder.shape_src, maintaining the mesh simplification functionality while aligning with the refactored attribute naming convention.

Also applies to: 109-109, 115-115, 120-120

newton/examples/example_anymal_c_walk_on_sand.py (1)

168-168: LGTM! Mesh processing attributes correctly updated.

The attribute references have been consistently updated to follow the new naming convention:

• shape_geo_src → shape_src for accessing mesh data
• Shape scale now accessed via shape_scale

The collision shape filtering and mesh merging logic remains intact and functional.

Also applies to: 172-174

newton/solvers/xpbd/solver_xpbd.py (3)

314-314: LGTM! Material property parameter correctly updated.

The replacement of model.shape_materials with model.shape_material_mu correctly provides the friction coefficient array to the particle-shape contact solver, aligning with the refactoring to use individual material property arrays.

---

519-519: LGTM! Rigid contact material parameter correctly updated.

The replacement of model.shape_materials with model.shape_material_mu correctly provides the friction coefficient to the rigid body contact position solver.

---

633-633: LGTM! Restitution kernel parameters correctly updated.

The changes properly update the restitution kernel call:

• model.shape_materials → model.shape_material_restitution provides the specific restitution coefficients
• Contact thickness correctly split into rigid_contact_thickness0 and rigid_contact_thickness1 for more granular control

Both changes align with the broader refactoring to use individual property arrays.

Also applies to: 638-639

newton/solvers/featherstone/solver_featherstone.py (1)

401-405: LGTM! Correct implementation of material property flattening.

The replacement of the single model.shape_materials parameter with individual material property arrays (shape_material_ke, shape_material_kd, shape_material_kf, shape_material_ka, shape_material_mu) correctly implements the PR objective to remove structured types and use flat Warp arrays.

newton/sim/collide.py (4)

48-50: LGTM! Correct shape geometry attribute flattening.

The replacement of nested shape geometry attributes (shape_geo.type, shape_geo.scale, shape_geo.source) with flat attributes (shape_type, shape_scale, shape_source) correctly implements the structural refactoring to remove ShapeGeometry structs.

---

170-172: LGTM! Consistent shape geometry flattening.

The shape geometry attribute flattening is correctly applied to the create_soft_contacts kernel launch, maintaining consistency with the broader refactoring effort.

---

202-204: LGTM! Shape geometry flattening applied consistently.

The broadphase collision pairs kernel correctly uses the flattened shape geometry attributes, maintaining consistency across all collision-related kernel launches.

---

236-239: LGTM! Complete shape geometry attribute flattening.

The handle_contact_pairs kernel launch correctly implements the complete flattening of shape geometry attributes, including the transformation of shape_geo.thickness to shape_thickness. All changes align with the PR objectives.

newton/tests/test_mujoco_solver.py (7)

669-669: LGTM! Test updated for flattened shape type attribute.

The test correctly uses the new shape_type attribute instead of the nested shape_geo.type, maintaining the same test logic while adapting to the API changes.

---

673-676: LGTM! Material property attributes correctly flattened in tests.

The test code correctly updates from structured material properties (shape_materials.mu, shape_materials.ke, shape_materials.kd) to flattened arrays (shape_material_mu, shape_material_ke, shape_material_kd), preserving the original test validation logic.

---

851-851: LGTM! Material property assignment updated correctly.

The assignment to shape_material_mu correctly replaces the previous nested structure access, maintaining the test's functionality while using the new flattened API.

---

856-857: LGTM! Contact parameter assignments updated correctly.

The assignments to shape_material_ke and shape_material_kd correctly use the new flattened material property arrays, maintaining the test's ability to update contact parameters.

---

866-866: LGTM! Shape scale reading updated correctly.

The test correctly reads from the flattened shape_scale attribute instead of the nested shape_geo.scale, maintaining the same test functionality.

---

869-869: LGTM! Shape scale assignment updated correctly.

The assignment to the flattened shape_scale attribute correctly replaces the previous nested structure assignment, preserving the test's ability to update shape sizes.

---

1088-1089: LGTM! Shape source attribute access updated correctly.

The test correctly uses the renamed shape_src attribute (previously shape_geo_src) to access mesh objects and verify their maxhullvert properties, maintaining the test's validation logic.

newton/solvers/mujoco/solver_mujoco.py (5)

1789-1789: LGTM!

The attribute name change from model.shape_geo_src to model.shape_src is consistent with the refactoring to flat arrays.

---

1832-1833: LGTM!

The attribute name changes from model.shape_materials.mu to model.shape_material_mu are consistent with the refactoring to flat arrays and follow a clear naming convention.

---

2166-2166: LGTM!

The attribute name change from model.shape_materials.mu to model.shape_material_mu is consistent with the broader refactoring.

---

2371-2377: LGTM!

All attribute name changes are consistent with the refactoring from structured types to flat arrays:

• shape_materials.* → shape_material_*
• shape_geo.* → shape_*

The parameter updates correctly reflect the new flat array structure.

---

1651-2377: No remaining references to old structured types in solver_mujoco.py

All searches for shape_geo., shape_materials., and shape_geo_src returned no hits, confirming that the old structured‐type attributes have been fully removed or renamed. No further changes are required.

newton/solvers/vbd/solver_vbd.py (5)

540-540: LGTM! Parameter refactoring is consistent with the broader changes.

The replacement of structured ShapeMaterials with flat shape_material_mu array is correctly implemented. The usage pattern on line 572 properly accesses the friction coefficient via shape_material_mu[shape_index].

Also applies to: 572-572

---

1664-1664: LGTM! Kernel parameter passing is correctly updated.

The function signature and parameter passing to evaluate_body_particle_contact are consistent with the refactoring to use flat arrays instead of structured types.

Also applies to: 1815-1815

---

1926-1926: LGTM! Consistent parameter refactoring for no-self-contact kernel.

The function signature and parameter passing follow the same pattern as other kernel functions in the refactor.

Also applies to: 1958-1958

---

2728-2728: LGTM! Consistent usage across all solver methods.

The method correctly uses the refactored self.model.shape_material_mu attribute, maintaining consistency with other solver methods.

---

2552-2552: Confirmed: Model.shape_material_mu is defined and populated – approving change.

The Model class in newton/sim/model.py initializes

self.shape_material_mu = None

and the builder in newton/sim/builder.py replaces it with a wp.array, so the solver’s use of self.model.shape_material_mu is valid.

newton/solvers/xpbd/kernels.py (4)

134-134: LGTM: Function signature updated correctly

The parameter change from ShapeMaterials to shape_material_mu: wp.array(dtype=float) properly implements the refactoring to use flat arrays instead of structured types.

---

184-184: LGTM: Material property access updated correctly

The change from structured field access to direct array indexing (shape_material_mu[shape_index]) is consistent with the refactoring objectives and maintains the correct indexing logic.

---

2083-2083: LGTM: Material property parameters and access updated consistently

The function parameter and material property access changes correctly implement the flat array approach:

• Parameter changed to shape_material_mu: wp.array(dtype=float)
• Array access uses proper indexing for friction coefficient calculation

Also applies to: 2166-2169

---

2318-2318: LGTM: Restitution and contact thickness changes implemented correctly

The changes properly implement the refactoring:

• Restitution parameter changed to shape_material_restitution: wp.array(dtype=float)
• Contact thickness split into contact_thickness0 and contact_thickness1 arrays
• Thickness computation correctly sums both values: contact_thickness0[tid] + contact_thickness1[tid]
• Array access patterns for restitution are consistent with the new approach

This improves the handling of per-shape properties in contact pairs.

Also applies to: 2323-2324, 2348-2352, 2396-2396

newton/sim/model.py (3)

95-107: LGTM: Shape material properties properly flattened

The individual shape material property arrays are well-defined with:

• Consistent naming convention (shape_material_*)
• Proper type annotations (wp.array(dtype=float))
• Clear documentation for each property
• Complete coverage of all material properties (elastic stiffness, damping, friction, adhesion, friction coefficient, restitution)

This correctly implements the refactoring from composite ShapeMaterials to individual arrays.

---

109-123: LGTM: Shape geometry properties properly flattened and renamed

The individual shape geometry property arrays are well-implemented:

• Consistent naming convention (shape_* instead of shape_geo_*)
• Appropriate data types for each property (int32, bool, float, uint64, etc.)
• Complete coverage of geometry properties (type, solidity, thickness, source, scale, filter)
• shape_geo_src properly renamed to shape_src for consistency

This correctly implements the flattening of ShapeGeometry into individual arrays.

---

383-394: LGTM: Attribute frequency mapping updated correctly

The attribute_frequency dictionary updates properly reflect the new individual shape properties:

• All new shape material properties (shape_material_*) correctly mapped to "shape"
• All new shape geometry properties (shape_*) correctly mapped to "shape"
• Complete coverage of all the flattened attributes
• Maintains consistency with the existing attribute frequency system

This ensures that functionality depending on attribute frequency classification continues to work correctly.

newton/utils/render.py (2)

278-283: Arguments rename propagated correctly

The populate() call site has been updated to pass model.shape_src, model.shape_type, model.shape_scale, model.shape_thickness, and model.shape_is_solid, matching the new flattened arrays introduced in the model. Good catch – this prevents a runtime mismatch between the renderer and the model.

---

788-791: raycast_kernel signature correctly matches passed arguments

The raycast_kernel in newton/geometry/raycast.py is defined as:

def raycast_kernel(
    body_q: wp.array(dtype=wp.transform),
    shape_body: wp.array(dtype=int),
    shape_transform: wp.array(dtype=wp.transform),
    geom_type: wp.array(dtype=int),      # 4th parameter
    geom_size: wp.array(dtype=wp.vec3),   # 5th parameter
    ray_origin: wp.vec3,
    ray_direction: wp.vec3,
    lock: wp.array(dtype=wp.int32),
    ...
):

In newton/utils/render.py the launch call passes:

• 4th argument: self.model.shape_type (wp.array(dtype=int)) → matches geom_type
• 5th argument: self.model.shape_scale (wp.array(dtype=wp.vec3)) → matches geom_size

No changes are needed.

newton/sim/builder.py (8)

326-330: LGTM! Improved attribute naming consistency.

The systematic renaming from shape_geo_* to shape_* improves clarity by removing the redundant "geo" infix. The changes are consistent with the broader refactor to flatten shape geometry representation.

---

461-461: Correct property update.

The property correctly references the renamed shape_type attribute.

---

671-675: Consistent attribute list update.

The attribute names in the extension list correctly match the renamed attributes from the constructor.

---

1362-1362: Correct attribute reference update.

The visualization method correctly uses the renamed shape_type attribute.

---

2215-2357: Comprehensive attribute renaming in approximate_meshes method.

All shape attribute references have been systematically updated throughout the method:

• shape_geo_type → shape_type
• shape_geo_src → shape_src
• shape_geo_scale → shape_scale
• shape_geo_thickness → shape_thickness
• shape_geo_is_solid → shape_is_solid

The method logic remains unchanged and all references are consistent.

---

1776-1780: Correct attribute updates in add_shape method.

The shape creation method correctly uses all the renamed attributes while maintaining the same functionality.

---

3448-3484: Correct Model finalization with renamed attributes.

The finalize method correctly creates Warp arrays using all the renamed shape attributes:

• Uses shape_src for geometry sources
• Creates arrays for shape_type, shape_scale, shape_is_solid, shape_thickness
• Maintains all material property arrays with correct naming

The functionality is preserved while using the improved naming convention.

---

3677-3677: Final shape_count assignment updated correctly.

The Model's shape_count property correctly uses the renamed shape_type attribute.

newton/solvers/euler/kernels.py (6)

687-691: LGTM: Clean parameter declaration refactoring.

The individual material property arrays are well-named and properly typed. This flattened approach should improve GPU kernel performance compared to structured access patterns.

---

744-747: LGTM: Correct material property indexing.

The array indexing with shape_index is consistent across all material properties, and the averaging logic is preserved correctly.

---

803-807: LGTM: Consistent parameter declarations.

The material property parameter declarations match the pattern established in eval_particle_contacts, maintaining consistency across the codebase.

---

845-849: LGTM: Correct material property accumulation.

The indexing and accumulation logic is consistent for both shapes. The material properties are properly accessed using shape_a and shape_b indices, and the averaging calculation later divides by mat_nonzero correctly.

Also applies to: 853-857

---

1623-1627: LGTM: Correct kernel arguments.

The arguments passed match the kernel parameter declarations exactly, with proper ordering and naming convention.

---

1703-1707: LGTM: Consistent kernel arguments.

The arguments follow the same pattern as eval_body_contact_forces, maintaining consistency across both contact evaluation functions.

Reviewing files that changed from the base of the PR and between a3aa016 and 8d4f9bc.

• docs/migration.rst (1 hunks)
• newton/examples/example_anymal_c_walk_on_sand.py (1 hunks)
• newton/examples/example_g1.py (3 hunks)
• newton/examples/example_mujoco.py (1 hunks)

• newton/examples/example_mujoco.py
• docs/migration.rst

• newton/examples/example_anymal_c_walk_on_sand.py

• GitHub Check: Run GPU Unit Tests on AWS EC2 (Pull Request)
• GitHub Check: Run GPU Benchmarks (Pull Request)

newton/examples/example_g1.py (2)

39-39: LGTM: Explicit up_axis parameter improves clarity.

Making the up_axis="Y" parameter explicit instead of relying on defaults enhances code readability and ensures consistent behavior across the codebase.

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55-55: LGTM: Consistent explicit parameter usage.

Good practice to explicitly specify the up_axis="Y" parameter for consistency with the articulation builder and improved code clarity.