Combine sparse vectors in-place by first counting total `nnz` and then working backwards from the end. This removes the need for temporary buffers in `mju_combineSparse` and its callers and speeds up the function by ~10%.
PiperOrigin-RevId: 902530210
Change-Id: I4f48c327103552ab968d3915399c6067367bec9f
This provides a reduction from 26 to 18 constraints for trilinear and from 162 to 75 for quadratic. The assembly of the constraints becomes trivial. In total the speedup for a trilinear 3x3x3 grid is about 3x.
PiperOrigin-RevId: 902502398
Change-Id: I764772c7adef78da5a644f64701f842d36e4b543
The flex interpolation stiffness matrix within the implicit/implicitfast solvers is now built and factorized in a banded format instead of a dense one. This involves:
- Calculating the bandwidth based on the sparsity of the mass/damping matrix and the connectivity within flex cells.
- Allocating and populating a banded matrix `H`.
- Using `mju_cholFactorBand` and `mju_cholSolveBand` for factorization and solving.
This change improves performance for flexes with many DOFs but local coupling.
PiperOrigin-RevId: 901297952
Change-Id: I3efe06353d1903ea65ab30dc49685cede228bb68
This change introduces a `flex_cellcount` field to `mjModel` to specify the number of cells in each dimension for interpolated flexes. The stiffness computation, passive force calculation, and Jacobian derivatives are updated to operate on a per-cell basis, significantly improving performance by localizing computations to the nodes within each cell.
PiperOrigin-RevId: 901216393
Change-Id: Ic23132e609de11e71bb7fef8d1f139daad2ec264
This change introduces `nflexstiffness` and `flex_stiffnessadr` to allow flex stiffness matrices to have sizes other than the fixed 21 per element. Higher-order flexes can now store larger stiffness matrices based on their number of nodes. The `flex_stiffnessadr` array provides the starting index for each flex's stiffness data within the `flex_stiffness` array.
PiperOrigin-RevId: 899632263
Change-Id: Ie49182c46c3777acf0c6b492345edfcf62fb5e44
This change disallows calling `mjs_delete` on an mjSpec that has been attached to another mjSpec via `mjs_attach`. Attempting to delete an element from an attached spec will now result in an error. The Python bindings for `mjSpec.delete` have been updated to raise a ValueError when this occurs.
PiperOrigin-RevId: 897266695
Change-Id: Ic0670125a3028191ec50eca890f02b5910ec8b03
This removes the need to load these decoders via mj_loadAllPluginLibraries when using MuJoCo built with CMake. Other plugins are unchanged.
PiperOrigin-RevId: 897114719
Change-Id: Iee914cc5e05798186f384a67901f1cf86bc2f887
- Remove `lugre:viscous`, should now be added directly to actuator `damping`. Trying to do this for the user was incompatible with default inheritance (compounding instead of overriding).
- Move voltage limiting from the `saturation` to the `controller` attribute.
- Fix indexing issues in default inheritance.
PiperOrigin-RevId: 897087642
Change-Id: I5388c2633e15c7e223992e7eb5d6a28db75a6438
Add a warning in user_model.cc if a flex is not rigid and has no edge equality constraints or passive forces (edge stiffness, edge damping, or vertex damping). Such flexes would not affect the simulation. A test case is added to verify the warning.
PiperOrigin-RevId: 889215981
Change-Id: I481128e1456921b632719547c676d201fdfbe931
Add a new mjpEncoder plugin type mirroring the existing mjpDecoder pattern.
Encoders serialize an mjSpec + mjModel to an mjResource for a given format.
New API functions:
- mjp_registerEncoder: globally register an encoder
- mjp_defaultEncoder: zero-initialize an encoder struct
- mjp_findEncoder: look up an encoder by filename extension or content type
The mjfEncode callback takes (mjSpec*, mjModel*, mjVFS*, mjResource*) and
returns 0 on success. Writing to mjResource keeps symmetry with the decoder
reading from mjResource and leaves the door open for writable resource providers.
PiperOrigin-RevId: 889187898
Change-Id: I180771b2255b91dea188ac5e2cdc3a8f0fb85364
*** Reason for rollback ***
Rolling back obj/stl decoder inclusion as sources due to broken windows build.
*** Original change description ***
Include obj and stl decoder plugins as sources in CMake builds.
This removes the need to load these decoders via mj_loadAllPluginLibraries when using MuJoCo built with CMake. Other plugins are unchanged.
***
PiperOrigin-RevId: 885576586
Change-Id: I31e6fa4d10697862f7d800d0d771ca752747e36d
This removes the need to load these decoders via mj_loadAllPluginLibraries when using MuJoCo built with CMake. Other plugins are unchanged.
PiperOrigin-RevId: 885555524
Change-Id: I20aa5b6c55b678398345d49cb1c47667ae2bebcf
The frustum_top and frustum_bottom assignments in mjv_updateCamera used
the wrong elements of the zver array, causing the principal point cy
offset to be applied with an inverted sign. This shifted the rendered
image vertically by 2*cy pixels.
The flex-SDF algorithm uses the same logic as mesh-SDF. Previous to this change, the flex was instead colliding with the convex hull of the mesh generated automatically with marching cubes from the SDF.
PiperOrigin-RevId: 876420302
Change-Id: I3bf6552b6b8e108ba4c4209bbcf10fe5f2b2fd90
The `mjCOctree::ComputeSdfCoeffs` function has been replaced by `mjCOctree::ComputeSdf`. The new implementation removes the dependency on the `triangle_mesh_distance` library. Instead, it uses a provided `mjCBoundingVolumeHierarchy` to perform closest point queries on the mesh. The signed distance is computed by finding the closest triangle face via the BVH and determining the sign based on the dot product of the vector from the closest point on the triangle to the octree vertex and the triangle's normal.
Optional Laplacian smoothing has been added to the SDF coefficients. This helps smooth out potential discontinuities at octree level boundaries.
PiperOrigin-RevId: 875093374
Change-Id: I6fa53243a2dda107ccf255bc6b876ca5a4554d4f
This change introduces methods to cache and load the computed stiffness matrix and nodal masses for flex elements. The cache key is generated based on material properties (Young's modulus, Poisson's ratio), interpolation order, and the bounding box of the flex. This avoids redundant expensive computations when compiling models with identical flex definitions.
PiperOrigin-RevId: 874689771
Change-Id: I6d1e299baf294a984b507e2a2602b2c068610536
MujocoTest now loads plugins from MUJOCO_PLUGIN_DIR if set.
PluginTest is removed; all tests use MujocoTest directly.
testspeed binary loads plugins from MUJOCO_PLUGIN_DIR.
This is in preparation for moving common asset format parsing (obj, msh, stl, etc.) where we will always want to load those plugins.
PiperOrigin-RevId: 874194428
Change-Id: Id90805a9ba5de4627911b56d8b9c4ab4e1b29310
Yuval Tassa