Merge pull request #2390 from talregev:TalR/mesh

PiperOrigin-RevId: 723916727
Change-Id: I0abb0a12121c9eb291ccbc6afa0b4117bd389956

src/user/user_objects.h

@@ -31,6 +31,10 @@
 #include <mujoco/mjspec.h>
 #include "user/user_cache.h"
 #include "user/user_util.h"
+#include <tiny_obj_loader.h>
+
+using face_vertices_type =
+    decltype(tinyobj::mesh_t::num_face_vertices)::value_type;
 
 // forward declarations of all mjC/X classes
 class mjCError;
@@ -1010,7 +1014,7 @@ class mjCMesh: public mjCMesh_, private mjsMesh {
   std::vector<int> vertex_index_;
   std::vector<int> normal_index_;
   std::vector<int> texcoord_index_;
-  std::vector<unsigned char> num_face_vertices_;
+  std::vector<face_vertices_type> num_face_vertices_;
 
   // compute the volume and center-of-mass of the mesh given the face center
   void ComputeVolume(double CoM[3], mjtGeomInertia gtype, const double facecen[3]);