These flexes use only 24 DOFs (3 per vertex of the bounding box), while colliding with the full high resolution mesh.
On an 8x8x8 cube, the performance using DOFs at all vertices is
```
Simulation time : 18.74 s
Steps per second : 533
Realtime factor : 0.53 x
Time per step : 1874.4 µs
Contacts per step : 114.88
Constraints per step : 3322.51
Degrees of freedom : 1536
```
With the new implementation, it is the following:
```
Simulation time : 1.82 s
Steps per second : 5507
Realtime factor : 5.51 x
Time per step : 181.6 µs
Contacts per step : 38.84
Constraints per step : 155.36
Degrees of freedom : 24
```
PiperOrigin-RevId: 721008829
Change-Id: I833df027527db578d86667cc4b24295bcf6f7d22
This functionality is meant for fast copying of `mjModel` when synchronizing the visualization state, as in the Python passive viewer.
PiperOrigin-RevId: 699199743
Change-Id: I13a5160063eb09139ec1aee9c4969bc1c6f547f1
When built and run under address sanitizer (asan), `mj_markStack` and `mj_freeStack` are instrumented to detect leakage of mjData stack frames. When the compiler inlines several callees that call into mark/free in the same function, this instrumentation requires that the compiler retains separate mark/free calls for each original callee.
This change adds necessary optimization barriers to ensure that this is the case.
PiperOrigin-RevId: 609373993
Change-Id: I30dfd998fb66530735348e9715d92ee713f28210
Also add asan instrumentation to detect stack frame leakages (i.e. `mj_markStack` without a corresponding `mj_freeStack` in the same caller function).
PiperOrigin-RevId: 562625645
Change-Id: I4e3ff66ca0b9d08ed0a95cef45393db8e3053e22
This results in approximately 4-5% speedup in collision detection for particle.xml.
PiperOrigin-RevId: 562526634
Change-Id: Ia6487b1908618064d858bac484fe6861ed37a402
This implementation explicitly avoids calling division instructions (which are generally expensive) even when link-time optimization is not active or if the alloc functions aren't inlined for some reason.
Also make mj_stackAlloc cheaper for external callers who may be linking against MuJoCo dynamically (and therefore cannot benefit from inlining).
PiperOrigin-RevId: 561299565
Change-Id: Iea4be5bf6d351ddf0c9d1fd8bd89a0c207b39309
- Add private function `mj_arenaAlloc`. This is used internally to allocate memory from the arena.
- Add private function `mj_nefc` to count constraints. This function returns a tight upper bound on `d->nefc`. The number of counted constraints can be slightly bigger than exact `d->nefc` in the case of constraints with empty Jacobian, as when placing a frictional tendon between two world sites.
- Add new `memory` attribute to the `size` XML element for specification of arena memory size. This attribute is mutually exclusive with `nstack` and `njmax` specifications, which are now deprecated (but left around for the time being for legacy compatibility).
- Move `d->stack` to the end of the new arena space. The stack now grows in reverse from the end.
PiperOrigin-RevId: 479341539
Change-Id: Ie019c202e0908577ffc6f833a37920858116f667