Add engine settings to mjmModel.

PiperOrigin-RevId: 608915453
Change-Id: Ic58566d7a9cdb57e25954caec69f595c8c9ee88a

src/xml/xml_native_reader.cc

@@ -39,7 +39,6 @@
 #include "user/user_api.h"
 #include "user/user_composite.h"
 #include "user/user_flexcomp.h"
-#include "user/user_model.h"
 #include "user/user_util.h"
 #include "xml/xml_base.h"
 #include "xml/xml_util.h"
@@ -805,7 +804,10 @@ void mjXReader::Parse(XMLElement* root) {
   }
 
   // get model name
-  ReadAttrTxt(root, "model", model->modelname);
+  string modelname;
+  if (ReadAttrTxt(root, "model", modelname)) {
+    mjm_setString(model->spec.modelname, modelname.c_str());
+  }
 
   // get comment
   if (root->FirstChild() && root->FirstChild()->ToComment()) {
@@ -823,12 +825,12 @@ void mjXReader::Parse(XMLElement* root) {
 
   for (XMLElement* section = FirstChildElement(root, "option"); section;
        section = NextSiblingElement(section, "option")) {
-    Option(section, &model->option);
+    Option(section, &model->spec.option);
   }
 
   for (XMLElement* section = FirstChildElement(root, "size"); section;
        section = NextSiblingElement(section, "size")) {
-    Size(section, model);
+    Size(section, &model->spec);
   }
 
   //------------------ parse MJCF-specific sections
@@ -1096,7 +1098,7 @@ void mjXReader::Option(XMLElement* section, mjOption* opt) {
 
 
 // size section parser
-void mjXReader::Size(XMLElement* section, mjCModel* mod) {
+void mjXReader::Size(XMLElement* section, mjmModel* mod) {
   // read memory bytes
   {
     constexpr char err_msg[] =
@@ -2936,7 +2938,7 @@ void mjXReader::Custom(XMLElement* section) {
 void mjXReader::Visual(XMLElement* section) {
   string text, name;
   XMLElement* elem;
-  mjVisual* vis = &model->visual;
+  mjVisual* vis = &model->spec.visual;
 
   // iterate over child elements
   elem = FirstChildElement(section);

src/xml/xml_native_reader.h

@@ -22,7 +22,6 @@
 
 #include <mujoco/mujoco.h>
 #include "user/user_api.h"
-#include "user/user_model.h"
 #include "xml/xml_base.h"
 #include "xml/xml_util.h"
 
@@ -45,7 +44,7 @@ class mjXReader : public mjXBase {
   // XML sections embedded in all formats
   static void Compiler(tinyxml2::XMLElement* section, mjmModel* mod);  // compiler section
   static void Option(tinyxml2::XMLElement* section, mjOption* opt);    // option section
-  static void Size(tinyxml2::XMLElement* section, mjCModel* mod);      // size section
+  static void Size(tinyxml2::XMLElement* section, mjmModel* mod);      // size section
 
  private:
   // XML section specific to MJCF

src/xml/xml_native_writer.cc

@@ -775,7 +775,7 @@ string mjXWriter::Write(char *error, size_t error_sz) {
   // create document and root
   XMLDocument doc;
   XMLElement* root = doc.NewElement("mujoco");
-  root->SetAttribute("model", model->modelname.c_str());
+  root->SetAttribute("model", mjm_getString(model->modelname));
 
   // insert root
   doc.InsertFirstChild(root);

src/xml/xml_urdf.cc

@@ -97,11 +97,11 @@ void mjXURDF::Parse(
     }
 
     if ((section = FindSubElem(mjc, "option"))) {
-      mjXReader::Option(section, &model->option);
+      mjXReader::Option(section, &model->spec.option);
     }
 
     if ((section = FindSubElem(mjc, "size"))) {
-      mjXReader::Size(section, model);
+      mjXReader::Size(section, &model->spec);
     }
   }
 
@@ -109,7 +109,10 @@ void mjXURDF::Parse(
   model->spec.degree = false;
 
   // get model name
-  ReadAttrTxt(root, "name", model->modelname);
+  std::string modelname;
+  if (ReadAttrTxt(root, "name", modelname)) {
+    mjm_setString(model->spec.modelname, modelname.c_str());
+  }
 
   // find and register all materials
   MakeMaterials(root);