From d2efc0e154a27073d438eb546c81ba6556e95d30 Mon Sep 17 00:00:00 2001
From: Google DeepMind
Date: Thu, 29 Jan 2026 07:54:50 -0800
Subject: [PATCH] Add object-based accessors for mjData in WASM bindings.
PiperOrigin-RevId: 862736608
Change-Id: I0618e9d2af37e377bad1aead1b3fd1a12334df35
---
wasm/README.md | 17 +-
wasm/codegen/generated/bindings.cc | 301 +++++++++++++++++++++++------
wasm/codegen/generators/structs.py | 30 +++
wasm/codegen/templates/bindings.cc | 274 ++++++++++++++++++++------
wasm/tests/bindings_test.ts | 230 +++++++++++++++++++++-
5 files changed, 727 insertions(+), 125 deletions(-)
diff --git a/wasm/README.md b/wasm/README.md
index 68570ee6..b0f9f22f 100644
--- a/wasm/README.md
+++ b/wasm/README.md
@@ -110,6 +110,15 @@ write your application in C++ and compile it using Emscripten, you may want to
copy a subset of the `EMSCRIPTEN_BINDINGS` from `bindings.cc` into your
application’s source file.
+### Named Access
+
+The bindings support named access methods, similar to the Python bindings,
+allowing convenient access to model and data elements by name or index. For
+example, you can access a geometry by name using `model.geom('mygeom')` or a
+joint using `data.jnt('myjoint')`.
+
+For more details and examples of how to use named access, please refer to the [named access tests](tests/bindings_test.ts;l=2010-2487) and [documentation](https://mujoco.readthedocs.io/en/stable/python.html#named-access).
+
## Development
In order to change the bindings you will need to change the [`bindings.cc`](codegen/generated/bindings.cc)
@@ -180,13 +189,7 @@ welcome!
These bindings are not yet complete. While the main MuJoCo APIs (`mj_step`,
`mj_loadXML`, etc.) are well tested, other APIs (e.g., functions from
`mjspec.h`) remain untested in real web applications (though test code for
- the `mjspec` bindings does exist). One notable feature not yet supported in
- the WASM bindings, which has proved very useful in the Python bindings, is
- named access methods — where data distributed across multiple arrays in C can
- be conveniently accessed by name, e.g., `model.geom('mygeom')` or
- `data.joint('myjoint')`. Currently, this data must be accessed via the
- `mj_name2id` function. Adding support for these features is a high priority,
- as it affects user code written in JavaScript.
+ the `mjspec` bindings does exist).
2. **Improve the developer experience.**
There is still work to be done to improve the developer experience when
diff --git a/wasm/codegen/generated/bindings.cc b/wasm/codegen/generated/bindings.cc
index 175f7414..1c4a7896 100644
--- a/wasm/codegen/generated/bindings.cc
+++ b/wasm/codegen/generated/bindings.cc
@@ -46,6 +46,7 @@ namespace mujoco::wasm {
using emscripten::enum_;
using emscripten::function;
using emscripten::val;
+using emscripten::typed_memory_view;
using emscripten::return_value_policy::reference;
using emscripten::return_value_policy::take_ownership;
@@ -83,6 +84,24 @@ EMSCRIPTEN_DECLARE_VAL_TYPE(StringOrNull);
X_ACCESSOR( TUPLE, Tuple, mjOBJ_TUPLE, tuple, ntuple ) \
X_ACCESSOR( KEYFRAME, Keyframe, mjOBJ_KEY, key, nkey )
+// Macro to define accessors for different MuJoCo object types within mjData.
+// Each line calls X_ACCESSOR with the following arguments:
+// 1. NAME: The object type name in uppercase (e.g., ACTUATOR).
+// 2. Name: The object type name in CamelCase (e.g., Actuator).
+// 3. OBJTYPE: The corresponding mjOBJ_* enum value (e.g., mjOBJ_ACTUATOR).
+// 4. field: The name of the array field in mjData (e.g., actuator).
+// 5. nfield: The name of the count field in mjModel (e.g., nu).
+#define MJDATA_ACCESSORS \
+ X_ACCESSOR( ACTUATOR, Actuator, mjOBJ_ACTUATOR, actuator, nu ) \
+ X_ACCESSOR( BODY, Body, mjOBJ_BODY, body, nbody ) \
+ X_ACCESSOR( CAMERA, Camera, mjOBJ_CAMERA, cam, ncam ) \
+ X_ACCESSOR( GEOM, Geom, mjOBJ_GEOM, geom, ngeom ) \
+ X_ACCESSOR( JOINT, Joint, mjOBJ_JOINT, jnt, njnt ) \
+ X_ACCESSOR( LIGHT, Light, mjOBJ_LIGHT, light, nlight ) \
+ X_ACCESSOR( SENSOR, Sensor, mjOBJ_SENSOR, sensor, nsensor ) \
+ X_ACCESSOR( SITE, Site, mjOBJ_SITE, site, nsite ) \
+ X_ACCESSOR( TENDON, Tendon, mjOBJ_TENDON, tendon, ntendon )
+
// Raises an error if the given val is null or undefined.
// A macro is used so that the error contains the name of the variable.
// TODO(matijak): Remove this when we can handle strings using UNPACK_STRING?
@@ -211,40 +230,79 @@ using mjVisualScale = decltype(::mjVisual::scale);
// - dim1: The fixed dimension of the array if not dynamically sized. If "1",
// a single element is returned. Otherwise, it's used as the stride
// for the typed memory view.
-#define X(type, prefix, var, dim0, dim1) \
- auto var() const { \
- if constexpr (std::string_view(#dim0) == "nq") { \
- int start = model_->jnt_qposadr[id_]; \
- int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
- return emscripten::val(emscripten::typed_memory_view(end - start, model_->prefix##var + start)); \
- } else if constexpr (std::string_view(#dim0) == "nv") { \
- int start = model_->jnt_dofadr[id_]; \
- int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
- return emscripten::val(emscripten::typed_memory_view(end - start, model_->prefix##var + start)); \
- } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
- int start = model_->hfield_adr[id_]; \
- int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->hfield_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
- int start = model_->tex_adr[id_]; \
- int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->tex_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
- int start = model_->numeric_adr[id_]; \
- int count = model_->numeric_size[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->numeric_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
- int start = model_->tuple_adr[id_]; \
- int count = model_->tuple_size[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->prefix##var + start)); \
- } else { \
- if constexpr (std::string_view(#dim1) == "1") { \
- return model_->prefix##var[id_]; \
- } else { \
- return emscripten::val( \
- emscripten::typed_memory_view(dim1, model_->prefix##var + id_ * dim1)); \
- } \
- } \
+#define X(type, prefix, var, dim0, dim1) \
+ emscripten::val get_##var() const { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ return val(typed_memory_view(end - start, model_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ return val(typed_memory_view(end - start, model_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
+ int start = model_->hfield_adr[id_]; \
+ int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
+ return val(typed_memory_view(count, model_->hfield_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
+ int start = model_->tex_adr[id_]; \
+ int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
+ return val(typed_memory_view(count, model_->tex_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
+ int start = model_->numeric_adr[id_]; \
+ int count = model_->numeric_size[id_]; \
+ return val(typed_memory_view(count, model_->numeric_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
+ int start = model_->tuple_adr[id_]; \
+ int count = model_->tuple_size[id_]; \
+ return val(typed_memory_view(count, model_->prefix##var + start)); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(model_->prefix##var[id_]); \
+ } else { \
+ return val(typed_memory_view(dim1, model_->prefix##var + id_ * dim1)); \
+ } \
+ } \
+ } \
+ void set_##var(const emscripten::val& value) { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ val(typed_memory_view(end - start, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ val(typed_memory_view(end - start, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
+ int start = model_->hfield_adr[id_]; \
+ int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
+ val(typed_memory_view(count, model_->hfield_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
+ int start = model_->tex_adr[id_]; \
+ int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
+ val(typed_memory_view(count, model_->tex_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
+ int start = model_->numeric_adr[id_]; \
+ int count = model_->numeric_size[id_]; \
+ val(typed_memory_view(count, model_->numeric_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
+ int start = model_->tuple_adr[id_]; \
+ int count = model_->tuple_size[id_]; \
+ val(typed_memory_view(count, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ model_->prefix##var[id_] = value.as(); \
+ } else { \
+ val(typed_memory_view(dim1, model_->prefix##var + id_ * dim1)) \
+ .call("set", value); \
+ } \
+ } \
}
// Expands to a struct definition for each object type in MJMODEL_ACCESSORS.
@@ -254,24 +312,114 @@ using mjVisualScale = decltype(::mjVisual::scale);
// - A `name()` method to get the object's name using `mj_id2name`.
// - Member functions generated by the `MJMODEL_##NAME` macro, which in turn
// uses the `X` macro to define accessors for fields within `mjModel`.
-#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
- struct MjModel##Name##Accessor { \
- MjModel##Name##Accessor(mjModel* model, int id) : model_(model), id_(id) {} \
- \
- int id() const { return id_; } \
- std::string name() const { \
- return mj_id2name(model_, OBJTYPE, id_); \
- } \
- \
- MJMODEL_##NAME \
- \
- private: \
- mjModel* model_; \
- int id_; \
+#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ struct MjModel##Name##Accessor { \
+ MjModel##Name##Accessor(mjModel* model, int id) : model_(model), id_(id) {} \
+ \
+ int id() const { return id_; } \
+ std::string name() const { \
+ const char* name = mj_id2name(model_, OBJTYPE, id_); \
+ return name ? name : ""; \
+ } \
+ \
+ MJMODEL_##NAME \
+ \
+ private: \
+ mjModel* model_; \
+ int id_; \
};
MJMODEL_ACCESSORS
#undef X_ACCESSOR
+// Expands to a struct definition for each object type in MJDATA_ACCESSORS.
+// Each struct, named `MjData{Name}Accessor`, provides:
+// - A constructor taking an `mjData*`, an `mjModel*`, and an integer `id`.
+// - An `id()` method to get the object's index.
+// - A `name()` method to get the object's name using `mj_id2name`.
+// - Member functions generated by the `MJDATA_##NAME` macro, which in turn
+// uses the `X` macro to define accessors for fields within `mjData`.
+#undef MJ_M
+#define MJ_M(n) model_->n
+#undef X
+#define X(type, prefix, var, dim0, dim1) \
+ emscripten::val get_##var() const { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ return val(typed_memory_view(end - start, data_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(typed_memory_view(end - start, data_->prefix##var + start)); \
+ } else { \
+ return val(typed_memory_view( \
+ (end - start) * dim1, data_->prefix##var + start * dim1)); \
+ } \
+ } else if constexpr (std::string_view(#dim0) == "nsensordata") { \
+ int start = model_->sensor_adr[id_]; \
+ int count = model_->sensor_dim[id_]; \
+ return val(typed_memory_view(count, data_->sensordata + start)); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(data_->prefix##var[id_]); \
+ } else { \
+ return val(typed_memory_view(dim1, data_->prefix##var + id_ * dim1)); \
+ } \
+ } \
+ } \
+ void set_##var(const emscripten::val& value) { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ val(typed_memory_view(end - start, data_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ val(typed_memory_view(end - start, data_->prefix##var + start)) \
+ .call("set", value); \
+ } else { \
+ val(typed_memory_view((end - start) * dim1, \
+ data_->prefix##var + start * dim1)) \
+ .call("set", value); \
+ } \
+ } else if constexpr (std::string_view(#dim0) == "nsensordata") { \
+ int start = model_->sensor_adr[id_]; \
+ int count = model_->sensor_dim[id_]; \
+ val(typed_memory_view(count, data_->sensordata + start)) \
+ .call("set", value); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ data_->prefix##var[id_] = value.as(); \
+ } else { \
+ val(typed_memory_view(dim1, data_->prefix##var + id_ * dim1)) \
+ .call("set", value); \
+ } \
+ } \
+ }
+
+#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ struct MjData##Name##Accessor { \
+ MjData##Name##Accessor(mjData* data, mjModel* model, int id) : data_(data), model_(model), id_(id) {} \
+ \
+ int id() const { return id_; } \
+ std::string name() const { \
+ const char* name = mj_id2name(model_, OBJTYPE, id_); \
+ return name ? name : ""; \
+ } \
+ \
+ MJDATA_##NAME \
+ \
+ private: \
+ mjData* data_; \
+ mjModel* model_; \
+ int id_; \
+ };
+MJDATA_ACCESSORS
+#undef X_ACCESSOR
+
#undef X
#undef MJ_M
@@ -6778,6 +6926,28 @@ struct MjData {
void set_signature(uint64_t value) {
ptr_->signature = value;
}
+ // Generates functions to return accessor classes.
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, accessor_name, nfield) \
+ MjData##Name##Accessor accessor_name(const NumberOrString& val) const { \
+ if (val.isString()) { \
+ int id = mj_name2id(model, OBJTYPE, val.as().c_str()); \
+ if (id == -1) { \
+ mju_error("%s", KeyErrorMessage(model, OBJTYPE, model->nfield, val.as(), #accessor_name).c_str()); \
+ } \
+ return MjData##Name##Accessor(ptr_, model, id); \
+ } else if (val.isNumber()) { \
+ int id = val.as(); \
+ if (id < 0 || id >= model->nfield) { \
+ mju_error("%s", IndexErrorMessage(id, model->nfield, #accessor_name).c_str()); \
+ } \
+ return MjData##Name##Accessor(ptr_, model, id); \
+ } else { \
+ mju_error(#accessor_name "() argument must be a string or number"); \
+ return MjData##Name##Accessor(nullptr, nullptr, 0); \
+ } \
+ }
+ MJDATA_ACCESSORS
+ #undef X_ACCESSOR
private:
mjData* ptr_;
@@ -11048,19 +11218,33 @@ EMSCRIPTEN_BINDINGS(mujoco_bindings) {
.value("mjWRAP_CYLINDER", mjWRAP_CYLINDER);
// Bindings for the MjModel accessor classes.
- #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::var)
- #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
- { \
- using Accessor = MjModel##Name##Accessor; \
- emscripten::class_("MjModel" #Name "Accessor") \
- .property("id", &Accessor::id) \
- .property("name", &Accessor::name) \
- MJMODEL_##NAME; \
+ #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::get_##var, &Accessor::set_##var)
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ { \
+ using Accessor = MjModel##Name##Accessor; \
+ emscripten::class_("MjModel" #Name "Accessor") \
+ .property("id", &Accessor::id) \
+ .property("name", &Accessor::name) \
+ MJMODEL_##NAME; \
}
MJMODEL_ACCESSORS
#undef X
#undef X_ACCESSOR
+ // Bindings for the MjData accessor classes.
+ #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::get_##var, &Accessor::set_##var)
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ { \
+ using Accessor = MjData##Name##Accessor; \
+ emscripten::class_("MjData" #Name "Accessor") \
+ .property("id", &Accessor::id) \
+ .property("name", &Accessor::name) \
+ MJDATA_##NAME; \
+ }
+ MJDATA_ACCESSORS
+ #undef X
+ #undef X_ACCESSOR
+
emscripten::class_("MjContact")
.constructor<>()
.function("copy", &MjContact::copy, take_ownership())
@@ -11086,6 +11270,11 @@ EMSCRIPTEN_BINDINGS(mujoco_bindings) {
emscripten::class_("MjData")
.constructor()
.constructor()
+ // Binds the functions on MjData that return accessors.
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field_name, nfield) \
+ .function(#field_name, &MjData::field_name)
+ MJDATA_ACCESSORS
+ #undef X_ACCESSOR
.property("M", &MjData::M)
.property("act", &MjData::act)
.property("act_dot", &MjData::act_dot)
diff --git a/wasm/codegen/generators/structs.py b/wasm/codegen/generators/structs.py
index 1dae82cf..f6282693 100644
--- a/wasm/codegen/generators/structs.py
+++ b/wasm/codegen/generators/structs.py
@@ -413,6 +413,30 @@ def build_struct_header(
MJMODEL_ACCESSORS
#undef X_ACCESSOR""".lstrip())
+ elif w == "MjData":
+ builder.line("""
+ // Generates functions to return accessor classes.
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, accessor_name, nfield) \\
+ MjData##Name##Accessor accessor_name(const NumberOrString& val) const { \\
+ if (val.isString()) { \\
+ int id = mj_name2id(model, OBJTYPE, val.as().c_str()); \\
+ if (id == -1) { \\
+ mju_error("%s", KeyErrorMessage(model, OBJTYPE, model->nfield, val.as(), #accessor_name).c_str()); \\
+ } \\
+ return MjData##Name##Accessor(ptr_, model, id); \\
+ } else if (val.isNumber()) { \\
+ int id = val.as(); \\
+ if (id < 0 || id >= model->nfield) { \\
+ mju_error("%s", IndexErrorMessage(id, model->nfield, #accessor_name).c_str()); \\
+ } \\
+ return MjData##Name##Accessor(ptr_, model, id); \\
+ } else { \\
+ mju_error(#accessor_name "() argument must be a string or number"); \\
+ return MjData##Name##Accessor(nullptr, nullptr, 0); \\
+ } \\
+ }
+ MJDATA_ACCESSORS
+ #undef X_ACCESSOR""".lstrip())
# define private struct members
builder.private()
@@ -518,6 +542,12 @@ def _build_struct_bindings(
if w == "MjData":
builder.line(".constructor()")
builder.line(".constructor()")
+ builder.line("""
+ // Binds the functions on MjData that return accessors.
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field_name, nfield) \\
+ .function(#field_name, &MjData::field_name)
+ MJDATA_ACCESSORS
+ #undef X_ACCESSOR""".lstrip())
elif w == "MjModel":
f1 = common.wrapped_function_name(
introspect_functions.FUNCTIONS["mj_loadXML"]
diff --git a/wasm/codegen/templates/bindings.cc b/wasm/codegen/templates/bindings.cc
index dadcdbc2..8e29a080 100644
--- a/wasm/codegen/templates/bindings.cc
+++ b/wasm/codegen/templates/bindings.cc
@@ -46,6 +46,7 @@ namespace mujoco::wasm {
using emscripten::enum_;
using emscripten::function;
using emscripten::val;
+using emscripten::typed_memory_view;
using emscripten::return_value_policy::reference;
using emscripten::return_value_policy::take_ownership;
@@ -83,6 +84,24 @@ EMSCRIPTEN_DECLARE_VAL_TYPE(StringOrNull);
X_ACCESSOR( TUPLE, Tuple, mjOBJ_TUPLE, tuple, ntuple ) \
X_ACCESSOR( KEYFRAME, Keyframe, mjOBJ_KEY, key, nkey )
+// Macro to define accessors for different MuJoCo object types within mjData.
+// Each line calls X_ACCESSOR with the following arguments:
+// 1. NAME: The object type name in uppercase (e.g., ACTUATOR).
+// 2. Name: The object type name in CamelCase (e.g., Actuator).
+// 3. OBJTYPE: The corresponding mjOBJ_* enum value (e.g., mjOBJ_ACTUATOR).
+// 4. field: The name of the array field in mjData (e.g., actuator).
+// 5. nfield: The name of the count field in mjModel (e.g., nu).
+#define MJDATA_ACCESSORS \
+ X_ACCESSOR( ACTUATOR, Actuator, mjOBJ_ACTUATOR, actuator, nu ) \
+ X_ACCESSOR( BODY, Body, mjOBJ_BODY, body, nbody ) \
+ X_ACCESSOR( CAMERA, Camera, mjOBJ_CAMERA, cam, ncam ) \
+ X_ACCESSOR( GEOM, Geom, mjOBJ_GEOM, geom, ngeom ) \
+ X_ACCESSOR( JOINT, Joint, mjOBJ_JOINT, jnt, njnt ) \
+ X_ACCESSOR( LIGHT, Light, mjOBJ_LIGHT, light, nlight ) \
+ X_ACCESSOR( SENSOR, Sensor, mjOBJ_SENSOR, sensor, nsensor ) \
+ X_ACCESSOR( SITE, Site, mjOBJ_SITE, site, nsite ) \
+ X_ACCESSOR( TENDON, Tendon, mjOBJ_TENDON, tendon, ntendon )
+
// Raises an error if the given val is null or undefined.
// A macro is used so that the error contains the name of the variable.
// TODO(matijak): Remove this when we can handle strings using UNPACK_STRING?
@@ -206,40 +225,79 @@ val get_mjRNDSTRING() { return MakeValArray3(mjRNDSTRING); }
// - dim1: The fixed dimension of the array if not dynamically sized. If "1",
// a single element is returned. Otherwise, it's used as the stride
// for the typed memory view.
-#define X(type, prefix, var, dim0, dim1) \
- auto var() const { \
- if constexpr (std::string_view(#dim0) == "nq") { \
- int start = model_->jnt_qposadr[id_]; \
- int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
- return emscripten::val(emscripten::typed_memory_view(end - start, model_->prefix##var + start)); \
- } else if constexpr (std::string_view(#dim0) == "nv") { \
- int start = model_->jnt_dofadr[id_]; \
- int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
- return emscripten::val(emscripten::typed_memory_view(end - start, model_->prefix##var + start)); \
- } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
- int start = model_->hfield_adr[id_]; \
- int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->hfield_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
- int start = model_->tex_adr[id_]; \
- int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->tex_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
- int start = model_->numeric_adr[id_]; \
- int count = model_->numeric_size[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->numeric_data + start)); \
- } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
- int start = model_->tuple_adr[id_]; \
- int count = model_->tuple_size[id_]; \
- return emscripten::val(emscripten::typed_memory_view(count, model_->prefix##var + start)); \
- } else { \
- if constexpr (std::string_view(#dim1) == "1") { \
- return model_->prefix##var[id_]; \
- } else { \
- return emscripten::val( \
- emscripten::typed_memory_view(dim1, model_->prefix##var + id_ * dim1)); \
- } \
- } \
+#define X(type, prefix, var, dim0, dim1) \
+ emscripten::val get_##var() const { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ return val(typed_memory_view(end - start, model_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ return val(typed_memory_view(end - start, model_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
+ int start = model_->hfield_adr[id_]; \
+ int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
+ return val(typed_memory_view(count, model_->hfield_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
+ int start = model_->tex_adr[id_]; \
+ int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
+ return val(typed_memory_view(count, model_->tex_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
+ int start = model_->numeric_adr[id_]; \
+ int count = model_->numeric_size[id_]; \
+ return val(typed_memory_view(count, model_->numeric_data + start)); \
+ } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
+ int start = model_->tuple_adr[id_]; \
+ int count = model_->tuple_size[id_]; \
+ return val(typed_memory_view(count, model_->prefix##var + start)); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(model_->prefix##var[id_]); \
+ } else { \
+ return val(typed_memory_view(dim1, model_->prefix##var + id_ * dim1)); \
+ } \
+ } \
+ } \
+ void set_##var(const emscripten::val& value) { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ val(typed_memory_view(end - start, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ val(typed_memory_view(end - start, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nhfielddata") { \
+ int start = model_->hfield_adr[id_]; \
+ int count = model_->hfield_nrow[id_] * model_->hfield_ncol[id_]; \
+ val(typed_memory_view(count, model_->hfield_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "ntexdata") { \
+ int start = model_->tex_adr[id_]; \
+ int count = model_->tex_height[id_] * model_->tex_width[id_] * model_->tex_nchannel[id_]; \
+ val(typed_memory_view(count, model_->tex_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nnumericdata") { \
+ int start = model_->numeric_adr[id_]; \
+ int count = model_->numeric_size[id_]; \
+ val(typed_memory_view(count, model_->numeric_data + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "ntupledata") { \
+ int start = model_->tuple_adr[id_]; \
+ int count = model_->tuple_size[id_]; \
+ val(typed_memory_view(count, model_->prefix##var + start)) \
+ .call("set", value); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ model_->prefix##var[id_] = value.as(); \
+ } else { \
+ val(typed_memory_view(dim1, model_->prefix##var + id_ * dim1)) \
+ .call("set", value); \
+ } \
+ } \
}
// Expands to a struct definition for each object type in MJMODEL_ACCESSORS.
@@ -249,24 +307,114 @@ val get_mjRNDSTRING() { return MakeValArray3(mjRNDSTRING); }
// - A `name()` method to get the object's name using `mj_id2name`.
// - Member functions generated by the `MJMODEL_##NAME` macro, which in turn
// uses the `X` macro to define accessors for fields within `mjModel`.
-#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
- struct MjModel##Name##Accessor { \
- MjModel##Name##Accessor(mjModel* model, int id) : model_(model), id_(id) {} \
- \
- int id() const { return id_; } \
- std::string name() const { \
- return mj_id2name(model_, OBJTYPE, id_); \
- } \
- \
- MJMODEL_##NAME \
- \
- private: \
- mjModel* model_; \
- int id_; \
+#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ struct MjModel##Name##Accessor { \
+ MjModel##Name##Accessor(mjModel* model, int id) : model_(model), id_(id) {} \
+ \
+ int id() const { return id_; } \
+ std::string name() const { \
+ const char* name = mj_id2name(model_, OBJTYPE, id_); \
+ return name ? name : ""; \
+ } \
+ \
+ MJMODEL_##NAME \
+ \
+ private: \
+ mjModel* model_; \
+ int id_; \
};
MJMODEL_ACCESSORS
#undef X_ACCESSOR
+// Expands to a struct definition for each object type in MJDATA_ACCESSORS.
+// Each struct, named `MjData{Name}Accessor`, provides:
+// - A constructor taking an `mjData*`, an `mjModel*`, and an integer `id`.
+// - An `id()` method to get the object's index.
+// - A `name()` method to get the object's name using `mj_id2name`.
+// - Member functions generated by the `MJDATA_##NAME` macro, which in turn
+// uses the `X` macro to define accessors for fields within `mjData`.
+#undef MJ_M
+#define MJ_M(n) model_->n
+#undef X
+#define X(type, prefix, var, dim0, dim1) \
+ emscripten::val get_##var() const { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ return val(typed_memory_view(end - start, data_->prefix##var + start)); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(typed_memory_view(end - start, data_->prefix##var + start)); \
+ } else { \
+ return val(typed_memory_view( \
+ (end - start) * dim1, data_->prefix##var + start * dim1)); \
+ } \
+ } else if constexpr (std::string_view(#dim0) == "nsensordata") { \
+ int start = model_->sensor_adr[id_]; \
+ int count = model_->sensor_dim[id_]; \
+ return val(typed_memory_view(count, data_->sensordata + start)); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ return val(data_->prefix##var[id_]); \
+ } else { \
+ return val(typed_memory_view(dim1, data_->prefix##var + id_ * dim1)); \
+ } \
+ } \
+ } \
+ void set_##var(const emscripten::val& value) { \
+ if constexpr (std::string_view(#dim0) == "nq") { \
+ int start = model_->jnt_qposadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_qposadr[id_ + 1] : model_->nq; \
+ val(typed_memory_view(end - start, data_->prefix##var + start)) \
+ .call("set", value); \
+ } else if constexpr (std::string_view(#dim0) == "nv") { \
+ int start = model_->jnt_dofadr[id_]; \
+ int end = (id_ < model_->njnt - 1) ? model_->jnt_dofadr[id_ + 1] : model_->nv; \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ val(typed_memory_view(end - start, data_->prefix##var + start)) \
+ .call("set", value); \
+ } else { \
+ val(typed_memory_view((end - start) * dim1, \
+ data_->prefix##var + start * dim1)) \
+ .call("set", value); \
+ } \
+ } else if constexpr (std::string_view(#dim0) == "nsensordata") { \
+ int start = model_->sensor_adr[id_]; \
+ int count = model_->sensor_dim[id_]; \
+ val(typed_memory_view(count, data_->sensordata + start)) \
+ .call("set", value); \
+ } else { \
+ if constexpr (std::string_view(#dim1) == "1") { \
+ data_->prefix##var[id_] = value.as(); \
+ } else { \
+ val(typed_memory_view(dim1, data_->prefix##var + id_ * dim1)) \
+ .call("set", value); \
+ } \
+ } \
+ }
+
+#define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ struct MjData##Name##Accessor { \
+ MjData##Name##Accessor(mjData* data, mjModel* model, int id) : data_(data), model_(model), id_(id) {} \
+ \
+ int id() const { return id_; } \
+ std::string name() const { \
+ const char* name = mj_id2name(model_, OBJTYPE, id_); \
+ return name ? name : ""; \
+ } \
+ \
+ MJDATA_##NAME \
+ \
+ private: \
+ mjData* data_; \
+ mjModel* model_; \
+ int id_; \
+ };
+MJDATA_ACCESSORS
+#undef X_ACCESSOR
+
#undef X
#undef MJ_M
@@ -644,19 +792,33 @@ EMSCRIPTEN_BINDINGS(mujoco_bindings) {
// {{ ENUM_BINDINGS }}
// Bindings for the MjModel accessor classes.
- #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::var)
- #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
- { \
- using Accessor = MjModel##Name##Accessor; \
- emscripten::class_("MjModel" #Name "Accessor") \
- .property("id", &Accessor::id) \
- .property("name", &Accessor::name) \
- MJMODEL_##NAME; \
+ #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::get_##var, &Accessor::set_##var)
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ { \
+ using Accessor = MjModel##Name##Accessor; \
+ emscripten::class_("MjModel" #Name "Accessor") \
+ .property("id", &Accessor::id) \
+ .property("name", &Accessor::name) \
+ MJMODEL_##NAME; \
}
MJMODEL_ACCESSORS
#undef X
#undef X_ACCESSOR
+ // Bindings for the MjData accessor classes.
+ #define X(type, prefix, var, dim0, dim1) .property(#var, &Accessor::get_##var, &Accessor::set_##var)
+ #define X_ACCESSOR(NAME, Name, OBJTYPE, field, nfield) \
+ { \
+ using Accessor = MjData##Name##Accessor; \
+ emscripten::class_("MjData" #Name "Accessor") \
+ .property("id", &Accessor::id) \
+ .property("name", &Accessor::name) \
+ MJDATA_##NAME; \
+ }
+ MJDATA_ACCESSORS
+ #undef X
+ #undef X_ACCESSOR
+
// {{ STRUCTS_BINDINGS }}
emscripten::class_("MjVFS")
diff --git a/wasm/tests/bindings_test.ts b/wasm/tests/bindings_test.ts
index 3b524964..a7f30eb9 100644
--- a/wasm/tests/bindings_test.ts
+++ b/wasm/tests/bindings_test.ts
@@ -45,17 +45,17 @@ const TEST_XML = `
+
-
+
-
-
+
+
@@ -900,7 +900,7 @@ describe('MuJoCo WASM Bindings', () => {
// Corresponds to bindings_test.py:test_can_read_array
it('should read an array from the model', () => {
const expected =
- new Float64Array([0, 0, 0, 0, 0, 0.1, 0, 0, 0, 0, 0, 0, 42, 0, 42]);
+ new Float64Array([0, 0, 0, 0, 0, 0.1, 0, 0, 1, 2, 0, 1, 42, 0, 42]);
const bodyPos = new Float64Array(model!.body_pos);
expectArraysEqual(bodyPos, expected);
});
@@ -1881,7 +1881,7 @@ describe('MuJoCo WASM Bindings', () => {
model!.geom('badgeom');
})
.toThrowError(
- `MuJoCo Error: Invalid name 'badgeom' for geom. Valid names: \['mybox', 'myplane'\]`);
+ `MuJoCo Error: Invalid name 'badgeom' for geom. Valid names: ['mocap-sphere', 'mybox', 'myplane']`);
});
// Corresponds to
@@ -2160,6 +2160,223 @@ describe('MuJoCo WASM Bindings', () => {
});
});
+ describe('MjData named access', () => {
+ it('should support named access for MjData', () => {
+ mujoco.mj_forward(model!, data!);
+
+ // Actuator
+ expect(model!.nu).toBe(1);
+ const actuator = data!.actuator(0);
+ expect(actuator.name).toBe('myactuator');
+ expect(actuator.velocity).toBe(0);
+ expect(actuator.force).toBe(0);
+ expectArraysClose(
+ actuator.moment, new Float64Array([1, 0, 0, 0, 0, 0, 0, 0, 0, 0]));
+
+ // Body
+ expect(model!.nbody).toBe(5);
+ expect(data!.body('mybox').name).toBe('mybox');
+ expectArraysClose(
+ data!.body('mybox').xpos, new Float64Array([0, 0, 0.1]));
+ expect(data!.body('myhinge-body').name).toBe('myhinge-body');
+ expectArraysClose(
+ data!.body('myhinge-body').xpos, new Float64Array([0, 0, 1]));
+ expect(data!.body('myball-body').name).toBe('myball-body');
+ expectArraysClose(
+ data!.body('myball-body').xpos, new Float64Array([2, 0, 1]));
+ expect(data!.body('mocap-body').name).toBe('mocap-body');
+ expectArraysClose(
+ data!.body('mocap-body').xpos, new Float64Array([42, 0, 42]));
+
+ // Geom
+ expect(model!.ngeom).toBe(3);
+ expect(data!.geom('myplane').name).toBe('myplane');
+ expectArraysClose(
+ data!.geom('myplane').xpos, new Float64Array([0, 0, 0]));
+ expectArraysClose(
+ data!.geom('myplane').xmat,
+ new Float64Array([1, 0, 0, 0, 1, 0, 0, 0, 1]));
+
+ expect(data!.geom('mybox').name).toBe('mybox');
+ expectArraysClose(
+ data!.geom('mybox').xpos, new Float64Array([0, 0, 0.1]));
+ expectArraysClose(
+ data!.geom('mybox').xmat,
+ new Float64Array([1, 0, 0, 0, 1, 0, 0, 0, 1]));
+
+ expect(data!.geom('mocap-sphere').name).toBe('mocap-sphere');
+ expectArraysClose(
+ data!.geom('mocap-sphere').xpos, new Float64Array([42, 0, 42]));
+ expectArraysClose(
+ data!.geom('mocap-sphere').xmat,
+ new Float64Array([1, 0, 0, 0, 1, 0, 0, 0, 1]));
+
+ // Joint
+ expect(model!.njnt).toBe(3);
+ const freeJnt = data!.jnt('myfree');
+ expect(freeJnt.name).toBe('myfree');
+ expectArraysClose(freeJnt.xanchor, new Float64Array([0, 0, 0.1]));
+ expectArraysClose(freeJnt.xaxis, new Float64Array([0, 0, 1]));
+
+ const hingeJnt = data!.jnt('myhinge');
+ expect(hingeJnt.name).toBe('myhinge');
+ expectArraysClose(hingeJnt.xanchor, new Float64Array([0, 0, 1]));
+ expectArraysClose(hingeJnt.xaxis, new Float64Array([0, 1, 0]));
+
+ const ballJnt = data!.jnt('myball');
+ expect(ballJnt.name).toBe('myball');
+ expectArraysClose(ballJnt.xanchor, new Float64Array([2, 0, 1]));
+ expectArraysClose(ballJnt.xaxis, new Float64Array([0, 0, 1]));
+
+ // Sensor
+ expect(model!.nsensor).toBe(2);
+ const jointvelSensor = data!.sensor('myjointvel');
+ expect(jointvelSensor.name).toBe('myjointvel');
+ expectArraysClose(jointvelSensor.data, new Float64Array([0]));
+
+ const accelSensor = data!.sensor('myaccelerometer');
+ expect(accelSensor.name).toBe('myaccelerometer');
+ expectArraysClose(accelSensor.data, new Float64Array([0, 0, 9.81]));
+
+ // Site
+ expect(model!.nsite).toBe(1);
+ const site = data!.site('mysite');
+ expect(site.name).toBe('mysite');
+ expectArraysClose(site.xpos, new Float64Array([0, 0, 0]));
+ expectArraysClose(
+ site.xmat, new Float64Array([1, 0, 0, 0, 1, 0, 0, 0, 1]));
+ });
+
+ // Corresponds to bindings_test.py:test_indexer_name_id
+ it('should support named and indexed access for MjData geoms', () => {
+ const xml = `
+
+
+
+
+
+
+
+
+
+ `;
+ const tempXmlFilename = '/tmp/geom_idx.xml';
+ writeXMLFile(tempXmlFilename, xml);
+ const model = mujoco.MjModel.mj_loadXML(tempXmlFilename);
+ const data = new mujoco.MjData(model);
+ try {
+ assertExists(model);
+ assertExists(data);
+ mujoco.mj_forward(model, data);
+
+ expect(data.geom('mygeom').id).toBe(0);
+ expect(data.geom('myothergeom').id).toBe(3);
+ expect(data.geom(0).name).toBe('mygeom');
+ expect(data.geom(1).name).toBe('');
+ expect(data.geom(2).name).toBe('');
+ expect(data.geom(3).name).toBe('myothergeom');
+ expect(data.geom(4).name).toBe('');
+
+ expect(data.geom(0).xpos[2]).toBeCloseTo(1);
+ expect(data.geom(1).xpos[2]).toBeCloseTo(2);
+ expect(data.geom(2).xpos[2]).toBeCloseTo(3);
+ expect(data.geom(3).xpos[2]).toBeCloseTo(4);
+ expect(data.geom(4).xpos[2]).toBeCloseTo(5);
+ } finally {
+ model?.delete();
+ data?.delete();
+ unlinkXMLFile(tempXmlFilename);
+ }
+ });
+
+ // Corresponds to bindings_test.py:test_named_indexing_invalid_names_in_data
+ it('should throw an error for invalid geom names in data', () => {
+ expect(() => {
+ data!.geom('badgeom');
+ })
+ .toThrowError(
+ `MuJoCo Error: Invalid name 'badgeom' for geom. Valid names: ['mocap-sphere', 'mybox', 'myplane']`);
+ });
+
+ // Corresponds to bindings_test.py:test_named_indexing_invalid_index_in_data
+ it('should throw an error for invalid geom indices in data', () => {
+ expect(() => {
+ data!.geom(3);
+ })
+ .toThrowError(
+ 'MuJoCo Error: Invalid index 3 for geom. Valid indices from 0 to 2');
+ expect(() => {
+ data!.geom(-1);
+ })
+ .toThrowError(
+ 'MuJoCo Error: Invalid index -1 for geom. Valid indices from 0 to 2');
+ });
+
+ // Corresponds to bindings_test.py:test_named_indexing_actuator_ctrl
+ it('should support named access for Actuator ctrl', () => {
+ const actuatorId = mujoco.mj_name2id(
+ model!, mujoco.mjtObj.mjOBJ_ACTUATOR.value, 'myactuator');
+ assertExists(actuatorId);
+
+ const actuator = data!.actuator('myactuator');
+ expect(actuator).toEqual(data!.actuator(actuatorId));
+ expect(actuator.ctrl).toEqual(data!.actuator(actuatorId)!.ctrl);
+
+ // Test that the indexer is returning a view into the underlying
+ data!.ctrl[actuatorId] = 5;
+ expect(actuator.ctrl).toBe(5);
+ actuator.ctrl = 7;
+ expect(data!.ctrl[actuatorId]).toBe(7);
+ });
+
+ // Corresponds to bindings_test.py:test_named_indexing_ragged_qpos
+ it('should support named access for Joint qpos', () => {
+ const balljointId =
+ mujoco.mj_name2id(model!, mujoco.mjtObj.mjOBJ_JOINT.value, 'myball');
+ assertExists(balljointId);
+
+ const ballJnt = data!.jnt('myball');
+ expect(ballJnt).toEqual(data!.jnt(balljointId));
+ expect(ballJnt.qpos).toEqual(data!.jnt(balljointId)!.qpos);
+
+ // Test that the indexer is returning a view into the underlying struct.
+ const qposFromIndexer = ballJnt.qpos;
+ const qposIdx = model!.jnt_qposadr[balljointId];
+ data!.qpos.set([4, 5, 6, 7], qposIdx);
+ expectArraysEqual(qposFromIndexer, new Float64Array([4, 5, 6, 7]));
+ ballJnt.qpos.set(new Float64Array([9, 8, 7, 6]))
+ expectArraysEqual(
+ data!.qpos.slice(qposIdx, qposIdx + 4),
+ new Float64Array([9, 8, 7, 6]));
+ });
+
+ // Corresponds to bindings_test.py:test_named_indexing_ragged2d_cdof
+ it('should support named access for Joint cdof', () => {
+ const freejointId =
+ mujoco.mj_name2id(model!, mujoco.mjtObj.mjOBJ_JOINT.value, 'myfree');
+ assertExists(freejointId);
+ mujoco.mj_forward(model!, data!);
+
+ const freeJnt = data!.jnt('myfree');
+ expect(freeJnt).toEqual(data!.jnt(freejointId));
+ expect(freeJnt.cdof).toEqual(data!.jnt(freejointId)!.cdof);
+ expect(freeJnt.cdof.length).toBe(36); // 6x6
+
+ // Test that the indexer is returning a view into the underlying
+ const cdofFromIndexer = freeJnt.cdof;
+ const dofIdx = model!.jnt_dofadr[freejointId];
+ const testArray = new Float64Array(36);
+ for (let i = 0; i < 36; i++) {
+ testArray[i] = i;
+ }
+ data!.cdof.set(testArray);
+ expectArraysEqual(freeJnt.cdof, testArray);
+ const expectedCdof = new Float64Array(36).fill(42);
+ freeJnt.cdof.set(expectedCdof);
+ expectArraysEqual(data!.cdof.slice(dofIdx, dofIdx + 36), expectedCdof);
+ });
+ });
+
it('should save model to buffer', () => {
assertExists(model);
const modelSize = mujoco.mj_sizeModel(model);
@@ -2279,4 +2496,5 @@ describe('MuJoCo WASM Bindings', () => {
unlinkXMLFile(mjbFilename);
}
});
+
});