Add mjs_makeMesh to create a builtin mesh.

PiperOrigin-RevId: 788538127
Change-Id: I999733399a1a0da07b0f915f34d31364ab8b3b52

include/mujoco/mjspec.h

@@ -70,6 +70,16 @@ typedef enum mjtMeshInertia_ {      // type of mesh inertia
   mjMESH_INERTIA_SHELL              // shell mesh inertia
 } mjtMeshInertia;
 
+typedef enum mjtMeshBuiltin_ {      // type of built-in procedural mesh
+  mjMESH_BUILTIN_NONE = 0,          // no built-in mesh
+  mjMESH_BUILTIN_SPHERE,            // sphere
+  mjMESH_BUILTIN_HEMISPHERE,        // hemisphere
+  mjMESH_BUILTIN_PRISM,             // prism
+  mjMESH_BUILTIN_CONE,              // cone
+  mjMESH_BUILTIN_TORUS,             // torus
+  mjMESH_BUILTIN_WEDGE,             // wedge
+  mjMESH_BUILTIN_PLATE,             // plate
+} mjtMeshBuiltin;
 
 typedef enum mjtBuiltin_ {         // type of built-in procedural texture
   mjBUILTIN_NONE = 0,              // no built-in texture

include/mujoco/mujoco.h

@@ -1545,6 +1545,8 @@ MJAPI mjsTexture* mjs_addTexture(mjSpec* s);
 // Add material.
 MJAPI mjsMaterial* mjs_addMaterial(mjSpec* s, const mjsDefault* def);
 
+// Sets the vertices and normals of a mesh.
+MJAPI int mjs_makeMesh(mjsMesh* mesh, mjtMeshBuiltin builtin, double* params, int nparams);
 
 //---------------------------------- Find and get utilities ----------------------------------------