The field now stores either an approximate or exact diagonal of the constraint matrix A, so the name is made more general.
PiperOrigin-RevId: 924244954
Change-Id: I62b2f76531fb88b7b3bf96e6769940197596702b
with a preconditioned Conjugate Gradient (CG) solver that operates
on the full system matrix.
The previous approach extracted flex DOFs into a reduced banded system,
factored it separately, and overwrote the global solve. This required
precomputed bandwidth (makeFlexBandwidth), parent-joint detection,
coupling corrections, and a FlexInterpContext struct — and only worked
for standalone flex trees without parent joints.
The new CG solver uses the already-factored global system (M - h*qDeriv)
as a preconditioner and adds the flex stiffness contribution via
matrix-free products (mjd_flexInterp_mulKD/mulK). This handles any
kinematic configuration — including flexes attached to articulated
chains or with parent joints — without sparsity pattern restrictions.
Before (`bunny_multicell`):
```
Simulation time : 50.80 s
Steps per second : 197
Realtime factor : 0.20 x
Time per step : 5080.3 µs
CG iters / step : 3.16
Contacts / step : 31.04
Constraints / step : 124.15
Degrees of freedom : 178
Dynamic memory usage : 0.4% of 100M
```
After:
```
Simulation time : 9.52 s
Steps per second : 1051
Realtime factor : 1.05 x
Time per step : 951.7 µs
CG iters / step : 3.21
Contacts / step : 30.90
Constraints / step : 123.61
Degrees of freedom : 178
Dynamic memory usage : 0.3% of 100M
```
PiperOrigin-RevId: 913758038
Change-Id: If5aa617b2d535c86aec9bd71c9e0003a2b38bdd7
The maximum depth of the octree used for SDF generation can now be specified in the mesh definition via `mjsMesh::octree_maxdepth`. The default value is 6.
PiperOrigin-RevId: 912494999
Change-Id: I6d828d1d3999b99d1210a6829a05b04fac591e1f
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
The `vertcollide` attribute in flex and flexcomp contact specifications has been removed since the next mjWarp release will support flex collisions. This attribute was previously used to enable vertex-based collisions by adding sphere geoms at flex vertices. The functionality associated with this attribute has been deprecated and removed from the XML parser, documentation, and internal data structures. Affected example XML files have also been updated.
PiperOrigin-RevId: 885595503
Change-Id: I6a78975f1bc540c09ea8b5306ff3be0962b7ab24
Adds a test which verifies that we can index into the texture buffer at offsets larger than can be represented by a 32-bit signed int.
PiperOrigin-RevId: 868756646
Change-Id: Ibc1a2b269fce41aec370611b0aab77803837e7a8
This change updates all size-related members within the `mjModel` struct from `int` to `mjtSize`. This allows MuJoCo to handle models with a larger number of elements. Corresponding changes were made to macros, function signatures, and I/O routines to accommodate the new `mjtSize` type.
PiperOrigin-RevId: 860144595
Change-Id: I701c6d607715d240766b6210a9773cd9e4258c59
This attribute allows specifying the intended output types (e.g., RGB, depth, normal) for each camera in the XML. The output types are stored as bit flags in `mjModel`.
PiperOrigin-RevId: 853316261
Change-Id: I1ad2e94102593cf402756f8f4c80509371ca86d2
- plugin system similar to mjpResourceProvider, but instead of loading a resource it converts an existing mjResource into an mjSpec.
- The returned spec is then composed into the referencing spec.
- This enables different file types to generate arbitrary specs, and allows us to separate format parsing from compilation code.
Follow up CLs will move some of the logic in src/engine for PNG, USD, KTX, OBJ loading into decoders.
The mj_parse function MjSpec from a given file, it's a more generic version of mj_parseXML.
In it's implementation, mj_parse as opposed to mj_parseXML will look for any registered decoder and
not assume we are striclty dealing with MJCF.
PiperOrigin-RevId: 826149497
Change-Id: I0ece26904280cb94bd5ded6dd5a565c539d60254
Yuval Tassa