Add MjcPhysicsEqualityConnectAPI to MjcPhysics for equality/connect parsing.

PiperOrigin-RevId: 867736241
Change-Id: I2d4e9abcb14280dcfbbf63ff5f888fb57350cfb6

include/mujoco/experimental/usd/mjcPhysics/equalityConnectAPI.h

@@ -0,0 +1,161 @@
+// Copyright 2025 DeepMind Technologies Limited
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef MJCPHYSICS_GENERATED_EQUALITYCONNECTAPI_H
+#define MJCPHYSICS_GENERATED_EQUALITYCONNECTAPI_H
+
+/// \file mjcPhysics/equalityConnectAPI.h
+
+#include <mujoco/experimental/usd/mjcPhysics/api.h>
+#include <pxr/base/gf/matrix4d.h>
+#include <pxr/base/gf/vec3d.h>
+#include <pxr/base/gf/vec3f.h>
+#include <pxr/base/tf/token.h>
+#include <pxr/base/tf/type.h>
+#include <pxr/base/vt/value.h>
+#include <pxr/pxr.h>
+#include <pxr/usd/usd/apiSchemaBase.h>
+#include <pxr/usd/usd/prim.h>
+#include <pxr/usd/usd/stage.h>
+
+PXR_NAMESPACE_OPEN_SCOPE
+
+class SdfAssetPath;
+
+// -------------------------------------------------------------------------- //
+// MJCEQUALITYCONNECTAPI                                                      //
+// -------------------------------------------------------------------------- //
+
+/// \class MjcPhysicsEqualityConnectAPI
+///
+/// API providing extension attributes to represent equality/connect
+/// constraints.
+///
+class MjcPhysicsEqualityConnectAPI : public UsdAPISchemaBase {
+ public:
+  /// Compile time constant representing what kind of schema this class is.
+  ///
+  /// \sa UsdSchemaKind
+  static const UsdSchemaKind schemaKind = UsdSchemaKind::SingleApplyAPI;
+
+  /// Construct a MjcPhysicsEqualityConnectAPI on UsdPrim \p prim .
+  /// Equivalent to MjcPhysicsEqualityConnectAPI::Get(prim.GetStage(),
+  /// prim.GetPath()) for a \em valid \p prim, but will not immediately throw an
+  /// error for an invalid \p prim
+  explicit MjcPhysicsEqualityConnectAPI(const UsdPrim& prim = UsdPrim())
+      : UsdAPISchemaBase(prim) {}
+
+  /// Construct a MjcPhysicsEqualityConnectAPI on the prim held by \p schemaObj
+  /// . Should be preferred over
+  /// MjcPhysicsEqualityConnectAPI(schemaObj.GetPrim()), as it preserves
+  /// SchemaBase state.
+  explicit MjcPhysicsEqualityConnectAPI(const UsdSchemaBase& schemaObj)
+      : UsdAPISchemaBase(schemaObj) {}
+
+  /// Destructor.
+  MJCPHYSICS_API
+  virtual ~MjcPhysicsEqualityConnectAPI();
+
+  /// Return a vector of names of all pre-declared attributes for this schema
+  /// class and all its ancestor classes.  Does not include attributes that
+  /// may be authored by custom/extended methods of the schemas involved.
+  MJCPHYSICS_API
+  static const TfTokenVector& GetSchemaAttributeNames(
+      bool includeInherited = true);
+
+  /// Return a MjcPhysicsEqualityConnectAPI holding the prim adhering to this
+  /// schema at \p path on \p stage.  If no prim exists at \p path on
+  /// \p stage, or if the prim at that path does not adhere to this schema,
+  /// return an invalid schema object.  This is shorthand for the following:
+  ///
+  /// \code
+  /// MjcPhysicsEqualityConnectAPI(stage->GetPrimAtPath(path));
+  /// \endcode
+  ///
+  MJCPHYSICS_API
+  static MjcPhysicsEqualityConnectAPI Get(const UsdStagePtr& stage,
+                                          const SdfPath& path);
+
+  /// Returns true if this <b>single-apply</b> API schema can be applied to
+  /// the given \p prim. If this schema can not be a applied to the prim,
+  /// this returns false and, if provided, populates \p whyNot with the
+  /// reason it can not be applied.
+  ///
+  /// Note that if CanApply returns false, that does not necessarily imply
+  /// that calling Apply will fail. Callers are expected to call CanApply
+  /// before calling Apply if they want to ensure that it is valid to
+  /// apply a schema.
+  ///
+  /// \sa UsdPrim::GetAppliedSchemas()
+  /// \sa UsdPrim::HasAPI()
+  /// \sa UsdPrim::CanApplyAPI()
+  /// \sa UsdPrim::ApplyAPI()
+  /// \sa UsdPrim::RemoveAPI()
+  ///
+  MJCPHYSICS_API
+  static bool CanApply(const UsdPrim& prim, std::string* whyNot = nullptr);
+
+  /// Applies this <b>single-apply</b> API schema to the given \p prim.
+  /// This information is stored by adding "MjcEqualityConnectAPI" to the
+  /// token-valued, listOp metadata \em apiSchemas on the prim.
+  ///
+  /// \return A valid MjcPhysicsEqualityConnectAPI object is returned upon
+  /// success. An invalid (or empty) MjcPhysicsEqualityConnectAPI object is
+  /// returned upon failure. See \ref UsdPrim::ApplyAPI() for conditions
+  /// resulting in failure.
+  ///
+  /// \sa UsdPrim::GetAppliedSchemas()
+  /// \sa UsdPrim::HasAPI()
+  /// \sa UsdPrim::CanApplyAPI()
+  /// \sa UsdPrim::ApplyAPI()
+  /// \sa UsdPrim::RemoveAPI()
+  ///
+  MJCPHYSICS_API
+  static MjcPhysicsEqualityConnectAPI Apply(const UsdPrim& prim);
+
+ protected:
+  /// Returns the kind of schema this class belongs to.
+  ///
+  /// \sa UsdSchemaKind
+  MJCPHYSICS_API
+  UsdSchemaKind _GetSchemaKind() const override;
+
+ private:
+  // needs to invoke _GetStaticTfType.
+  friend class UsdSchemaRegistry;
+  MJCPHYSICS_API
+  static const TfType& _GetStaticTfType();
+
+  static bool _IsTypedSchema();
+
+  // override SchemaBase virtuals.
+  MJCPHYSICS_API
+  const TfType& _GetTfType() const override;
+
+ public:
+  // ===================================================================== //
+  // Feel free to add custom code below this line, it will be preserved by
+  // the code generator.
+  //
+  // Just remember to:
+  //  - Close the class declaration with };
+  //  - Close the namespace with PXR_NAMESPACE_CLOSE_SCOPE
+  //  - Close the include guard with #endif
+  // ===================================================================== //
+  // --(BEGIN CUSTOM CODE)--
+};
+
+PXR_NAMESPACE_CLOSE_SCOPE
+
+#endif

include/mujoco/experimental/usd/mjcPhysics/tokens.h

@@ -792,6 +792,10 @@ struct MjcPhysicsTokensType {
   ///
   /// Schema identifier and family for MjcPhysicsEqualityAPI
   const TfToken MjcEqualityAPI;
+  /// \brief "MjcEqualityConnectAPI"
+  ///
+  /// Schema identifier and family for MjcPhysicsEqualityConnectAPI
+  const TfToken MjcEqualityConnectAPI;
   /// \brief "MjcEqualityJointAPI"
   ///
   /// Schema identifier and family for MjcPhysicsEqualityJointAPI