Added functionality for user payload data in mjSpec.

PiperOrigin-RevId: 738343134
Change-Id: I6217362ced9993afcd5a2914c78718ffe3bf753a

src/user/user_api.cc

@@ -769,6 +769,30 @@ mjsFrame* mjs_bodyToFrame(mjsBody** body) {
 
 
 
+// set user payload
+void mjs_setUserValue(mjsElement* element, const char* key, const void* data) {
+  mjCBase* baseC = static_cast<mjCBase*>(element);
+  baseC->SetUserValue(key, data);
+}
+
+
+
+// return user payload or NULL if none found
+const void* mjs_getUserValue(mjsElement* element, const char* key) {
+  mjCBase* baseC = static_cast<mjCBase*>(element);
+  return baseC->GetUserValue(key);
+}
+
+
+
+// delete user payload
+void mjs_deleteUserValue(mjsElement* element, const char* key) {
+  mjCBase* baseC = static_cast<mjCBase*>(element);
+  baseC->DeleteUserValue(key);
+}
+
+
+
 // get id
 int mjs_getId(mjsElement* element) {
   if (!element) {

src/user/user_api.h

@@ -378,6 +378,15 @@ MJAPI const char* mjs_resolveOrientation(double quat[4], mjtByte degree, const c
 // Transform body into a frame.
 MJAPI mjsFrame* mjs_bodyToFrame(mjsBody** body);
 
+// Set user payload.
+MJAPI void mjs_setUserValue(mjsElement* element, const char* key, const void* data);
+
+// Return user payload or NULL if none found.
+MJAPI const void* mjs_getUserValue(mjsElement* element, const char* key);
+
+// Delete user payload.
+MJAPI void mjs_deleteUserValue(mjsElement* element, const char* key);
+
 
 //---------------------------------- Initialization  -----------------------------------------------
 

src/user/user_objects.cc

@@ -766,6 +766,22 @@ void mjCBase::SetFrame(mjCFrame* _frame) {
 }
 
 
+void mjCBase::SetUserValue(std::string_view key, const void* data) {
+  user_payload_[std::string(key)] = data;
+}
+
+
+const void* mjCBase::GetUserValue(std::string_view key) {
+  auto found = user_payload_.find(std::string(key));
+  return found != user_payload_.end() ? found->second : nullptr;
+}
+
+
+void mjCBase::DeleteUserValue(std::string_view key) {
+  user_payload_.erase(std::string(key));
+}
+
+
 //------------------ class mjCBody implementation --------------------------------------------------
 
 // constructor

src/user/user_objects.h

@@ -23,11 +23,14 @@
 #include <map>
 #include <string>
 #include <string_view>
+#include <unordered_map>
 #include <utility>
 #include <vector>
 
+#include <mujoco/mjmodel.h>
+#include <mujoco/mjplugin.h>
 #include <mujoco/mjspec.h>
-#include <mujoco/mujoco.h>
+#include <mujoco/mjtnum.h>
 #include "user/user_cache.h"
 #include "user/user_util.h"
 #include <tiny_obj_loader.h>
@@ -274,12 +277,20 @@ class mjCBase : public mjCBase_ {
     }
   }
 
+  // Set and get user payload
+  void SetUserValue(std::string_view key, const void* data);
+  const void* GetUserValue(std::string_view key);
+  void DeleteUserValue(std::string_view key);
+
  protected:
   mjCBase();                                 // constructor
   mjCBase(const mjCBase& other);             // copy constructor
 
   // reference count for allowing deleting an attached object
   int refcount = 1;
+
+  // user payload
+  std::unordered_map<std::string, const void*> user_payload_;
 };
 
 
@@ -781,7 +792,7 @@ class mjCLight : public mjCLight_, private mjsLight {
 
 class mjCFlex_ : public mjCBase {
  protected:
-  int nvert;                              // number of verices
+  int nvert;                              // number of vertices
   int nnode;                              // number of nodes
   int nedge;                              // number of edges
   int nelem;                              // number of elements