Remove classname from mjs* structs.

PiperOrigin-RevId: 647277317
Change-Id: Ic3cb0d3bf890d6be2712c0538e21910a8f12ab44

doc/includes/references.h

@@ -1743,7 +1743,6 @@ typedef struct mjsFrame_ {         // frame specification
 typedef struct mjsJoint_ {         // joint specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjtJoint type;                   // joint type
 
   // kinematics
@@ -1781,7 +1780,6 @@ typedef struct mjsJoint_ {         // joint specification
 typedef struct mjsGeom_ {          // geom specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // classname
   mjtGeom type;                    // geom type
 
   // frame, size
@@ -1828,7 +1826,6 @@ typedef struct mjsGeom_ {          // geom specification
 typedef struct mjsSite_ {          // site specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // frame, size
   double pos[3];                   // position
@@ -1850,7 +1847,6 @@ typedef struct mjsSite_ {          // site specification
 typedef struct mjsCamera_ {        // camera specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // extrinsics
   double pos[3];                   // position
@@ -1878,7 +1874,6 @@ typedef struct mjsCamera_ {        // camera specification
 typedef struct mjsLight_ {         // light specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // frame
   double pos[3];                   // position
@@ -1904,7 +1899,6 @@ typedef struct mjsLight_ {         // light specification
 typedef struct mjsFlex_ {          // flex specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // contact properties
   int contype;                     // contact type
@@ -1943,7 +1937,6 @@ typedef struct mjsFlex_ {          // flex specification
 typedef struct mjsMesh_ {          // mesh specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjString* content_type;          // content type of file
   mjString* file;                  // mesh file
   double refpos[3];                // reference position
@@ -1974,7 +1967,6 @@ typedef struct mjsHField_ {        // height field specification
 typedef struct mjsSkin_ {          // skin specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjString* file;                  // skin file
   mjString* material;              // name of material used for rendering
   float rgba[4];                   // rgba when material is omitted
@@ -1999,7 +1991,6 @@ typedef struct mjsSkin_ {          // skin specification
 typedef struct mjsTexture_ {       // texture specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjtTexture type;                 // texture type
 
   // method 1: builtin
@@ -2031,7 +2022,6 @@ typedef struct mjsTexture_ {       // texture specification
 typedef struct mjsMaterial_ {      // material specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjString* texture;               // name of texture (empty: none)
   mjtByte texuniform;              // make texture cube uniform
   float texrepeat[2];              // texture repetition for 2D mapping
@@ -2047,7 +2037,6 @@ typedef struct mjsMaterial_ {      // material specification
 typedef struct mjsPair_ {          // pair specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjString* geomname1;             // name of geom 1
   mjString* geomname2;             // name of geom 2
 
@@ -2071,7 +2060,6 @@ typedef struct mjsExclude_ {       // exclude specification
 typedef struct mjsEquality_ {      // equality specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
   mjtEq type;                      // constraint type
   double data[mjNEQDATA];          // type-dependent data
   mjtByte active;                  // is equality initially active
@@ -2084,7 +2072,6 @@ typedef struct mjsEquality_ {      // equality specification
 typedef struct mjsTendon_ {        // tendon specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // stiffness, damping, friction
   double stiffness;                // stiffness coefficient
@@ -2118,7 +2105,6 @@ typedef struct mjsWrap_ {          // wrapping object specification
 typedef struct mjsActuator_ {      // actuator specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // gain, bias
   mjtGain gaintype;                // gain type
@@ -2160,7 +2146,6 @@ typedef struct mjsActuator_ {      // actuator specification
 typedef struct mjsSensor_ {        // sensor specification
   mjsElement* element;             // element type
   mjString* name;                  // name
-  mjString* classname;             // class name
 
   // sensor definition
   mjtSensor type;                  // type of sensor