Delete remaining code related to now-removed distance equality constraint.

PiperOrigin-RevId: 513391064
Change-Id: I47fc344708a580c1e99bd2753113aaa408812966

src/engine/engine_core_constraint.c

@@ -540,10 +540,6 @@ void mj_instantiateEquality(const mjModel* m, mjData* d) {
         size = 1;
         break;
 
-      case mjEQ_DISTANCE:
-        mju_error("distance equality constraints are no longer supported");
-        break;
-
       default:                    // SHOULD NOT OCCUR
         mju_error_i("Invalid equality constraint type %d", m->eq_type[i]);
       }
@@ -806,7 +802,7 @@ void mj_instantiateContact(const mjModel* m, mjData* d) {
       // skip contact if no DOFs affected
       if (NV==0) {
         con->efc_address = -1;
-        con->exclude = 4;
+        con->exclude = 3;
         continue;
       }
 
@@ -920,8 +916,8 @@ void mj_diagApprox(const mjModel* m, mjData* d) {
                     m->tendon_invweight0[m->eq_obj2id[id]]);
         break;
 
-      case mjEQ_DISTANCE:
-        mju_error("distance equality constraints are no longer supported");
+      default:
+        mju_error_i("Unknown constraint type type %d", d->efc_type[i]);    // SHOULD NOT OCCUR
       }
       break;
 

src/engine/engine_core_smooth.c

@@ -908,7 +908,7 @@ void mj_transmission(const mjModel* m, mjData* d) {
             }
           }
 
-          // excluded contact, get sparse or dense Jacobian, accumulate
+          // excluded contact in gap: get sparse or dense Jacobian, accumulate
           else if (con->exclude == 1) {
             counter++;
 
@@ -2034,10 +2034,6 @@ void mj_rnePostConstraint(const mjModel* m, mjData* d) {
       i++;
       break;
 
-    case mjEQ_DISTANCE:
-      mju_error("distance equality constraints are no longer supported");
-      break;
-
     default:
       mju_error_i("Unknown constraint type type %d", m->eq_type[id]);    // SHOULD NOT OCCUR
     }

src/engine/engine_vis_visualize.c

@@ -468,7 +468,6 @@ void mjv_addGeoms(const mjModel* m, mjData* d, const mjvOption* vopt,
   mjtNum *cur, *nxt, *xpos, *xfrc;
   mjtNum vec[3], end[3], axis[3], rod, len, det, tmp[9], quat[4];
   mjtByte broken;
-  mjContact *con;
   mjvGeom* thisgeom;
   mjvPerturb localpert;
   float scl = m->stat.meansize, rgba[4];
@@ -1667,39 +1666,6 @@ void mjv_addGeoms(const mjModel* m, mjData* d, const mjvOption* vopt,
         FINISH
       }
     }
-
-    // distance: find constraints at the end of the contact list
-    int j = d->ncon-1;
-    while (j>=0 && d->contact[j].exclude==3) {
-      // recover constraint id
-      int i = -d->contact[j].efc_address-2;
-
-      // segment = pos +/- normal*len
-      con = d->contact+j;
-      len = con->dist - m->eq_data[mjNEQDATA*i];
-      mju_addScl3(vec, con->pos, con->frame, 0.5*len);
-      mju_addScl3(end, con->pos, con->frame, -0.5*len);
-
-      // connect endpoints
-      START
-
-      // construct geom
-      sz[0] = scl * m->vis.scale.constraint;
-      mjv_makeConnector(thisgeom, mjGEOM_CAPSULE, sz[0],
-                        vec[0], vec[1], vec[2],
-                        end[0], end[1], end[2]);
-
-      f2f(thisgeom->rgba, m->vis.rgba.constraint, 4);
-
-      // vopt->label flag
-      if (vopt->label==mjLABEL_CONSTRAINT) {
-        makeLabel(m, mjOBJ_EQUALITY, i, thisgeom->label);
-      }
-
-      FINISH
-
-      j--;
-    }
   }
 
   // contact