Add frame support to the cable composite.

Also cleanup user_composite.cc includes.

PiperOrigin-RevId: 740730596
Change-Id: I05df59926d8e61de45fd6b2a3a63121b7a390448

src/user/user_composite.cc

@@ -12,25 +12,17 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include <mujoco/mjspec.h>
 #include "user/user_composite.h"
 
-#include <algorithm>
 #include <cmath>
-#include <cstddef>
-#include <cstdio>
 #include <cstring>
-#include <map>
-#include <stdexcept>
 #include <string>
-#include <utility>
 #include <vector>
 
-#include <mujoco/mjmacro.h>
 #include <mujoco/mjmodel.h>
+#include <mujoco/mjspec.h>
 #include <mujoco/mjtnum.h>
 #include "cc/array_safety.h"
-#include "engine/engine_io.h"
 #include "engine/engine_util_blas.h"
 #include "engine/engine_util_errmem.h"
 #include "engine/engine_util_misc.h"
@@ -40,9 +32,9 @@
 #include "user/user_util.h"
 
 namespace {
+
 namespace mju = ::mujoco::util;
-using mujoco::user::VectorToString;
-using mujoco::user::StringToVector;
+
 }  // namespace
 
 // strncpy with 0, return false
@@ -60,6 +52,7 @@ mjCComposite::mjCComposite(void) {
   type = mjCOMPTYPE_PARTICLE;
   count[0] = count[1] = count[2] = 1;
   mjuu_setvec(offset, 0, 0, 0);
+  frame = nullptr;
 
   // plugin variables
   mjs_defaultPlugin(&plugin);
@@ -381,6 +374,9 @@ mjsBody* mjCComposite::AddCableBody(mjCModel* model, mjsBody* body, int ix,
                            offset[1]+uservert[3*ix+1],
                            offset[2]+uservert[3*ix+2]);
     mjuu_copyvec(body->quat, this_quat, 4);
+    if (frame) {
+      mjs_setFrame(body->element, frame);
+    }
   } else {
     mjuu_setvec(body->pos, length_prev, 0, 0);
     double negquat[4] = {prev_quat[0], -prev_quat[1], -prev_quat[2], -prev_quat[3]};

src/user/user_composite.h

@@ -80,6 +80,7 @@ class mjCComposite {
   std::vector<float> uservert;    // user-specified vertex positions
   double size[3];                 // rope size (meaning depends on the shape)
   mjtCompShape curve[3];          // geometric shape
+  mjsFrame* frame;                // frame where the composite is defined
 
   // body names used in the skin
   std::vector<std::string> username;