Remove vertcollide attribute from flex contact.

The `vertcollide` attribute in flex and flexcomp contact specifications has been removed since the next mjWarp release will support flex collisions. This attribute was previously used to enable vertex-based collisions by adding sphere geoms at flex vertices. The functionality associated with this attribute has been deprecated and removed from the XML parser, documentation, and internal data structures. Affected example XML files have also been updated.

PiperOrigin-RevId: 885595503
Change-Id: I6a78975f1bc540c09ea8b5306ff3be0962b7ab24

doc/XMLreference.rst

@@ -3801,7 +3801,6 @@ saving the XML:
 
 .. _flexcomp-contact-internal:
 .. _flexcomp-contact-selfcollide:
-.. _flexcomp-contact-vertcollide:
 .. _flexcomp-contact-activelayers:
 .. _flexcomp-contact-contype:
 .. _flexcomp-contact-conaffinity:
@@ -3816,8 +3815,8 @@ saving the XML:
 .. _flexcomp-contact-passive:
 
 .. |body/flexcomp/contact attrib list| replace::
-   :at:`internal`, :at:`selfcollide`, :at:`vertcollide`, :at:`activelayers`, :at:`contype`, :at:`conaffinity`,
+   :at:`internal`, :at:`selfcollide`, :at:`activelayers`, :at:`contype`, :at:`conaffinity`, :at:`condim`,
-   :at:`condim`, :at:`priority`, :at:`friction`, :at:`solmix`, :at:`solimp`, :at:`margin`, :at:`gap`
+   :at:`priority`, :at:`friction`, :at:`solmix`, :at:`solimp`, :at:`margin`, :at:`gap`
 
 |body/flexcomp/contact attrib list|
    Same as in :ref:`flex/contact<flex-contact>`. All attributes are passed through to the automatically-generated flex.
@@ -4336,13 +4335,6 @@ extensions specific to flexes.
    **sap** in 1D and 2D, and **bvh** in 3D. Which strategy performs better depends on the specifics of the model. The
    automatic setting is just a simple rule which we have found to perform well in general.
 
-.. _flex-contact-vertcollide:
-
-:at:`vertcollide`: :at-val:`[true, false], "false"`
-   Enables or disables vertex collisions. if **true**, spherical geoms are added at the vertices of flex, with radius
-   equal to the radius of the flex. These geoms can collide with other geoms and are not visible by default. If
-   **false**, no additional geoms are added.
-
 .. _flex-contact-activelayers:
 
 :at:`activelayers`: :at-val:`int(1), "1"`

doc/XMLschema.rst

@@ -1564,9 +1564,6 @@
                .. grid-item::
                   :ref:`activelayers<flexcomp-contact-activelayers>`
 
-               .. grid-item::
-                  :ref:`vertcollide<flexcomp-contact-vertcollide>`
-
                .. grid-item::
                   :ref:`passive<flexcomp-contact-passive>`
 
@@ -1705,9 +1702,6 @@
                .. grid-item::
                   :ref:`activelayers<flex-contact-activelayers>`
 
-               .. grid-item::
-                  :ref:`vertcollide<flex-contact-vertcollide>`
-
                .. grid-item::
                   :ref:`passive<flex-contact-passive>`
 

doc/changelog.rst

@@ -29,6 +29,9 @@ General
 
      **Migration:** Replace assignments like ``joint.stiffness = val`` with ``joint.stiffness[0] = val``.
 
+   - The ``vertcollide`` field in :ref:`mjsContact` has been deprecated since the next release of :doc:`MuJoCo Warp <mjwarp/index>`
+     will support native flex collisions.
+
 
 Bug fixes
 ^^^^^^^^^

doc/includes/references.h

@@ -2228,7 +2228,6 @@ typedef struct mjsFlex_ {          // flex specification
   mjtByte internal;                // enable internal collisions
   mjtByte flatskin;                // render flex skin with flat shading
   int selfcollide;                 // mode for flex self collision
-  int vertcollide;                 // mode for vertex collision
   int passive;                     // mode for passive collisions
   int activelayers;                // number of active element layers in 3D
   int group;                       // group for visualization

include/mujoco/mjspec.h

@@ -442,7 +442,6 @@ typedef struct mjsFlex_ {          // flex specification
   mjtByte internal;                // enable internal collisions
   mjtByte flatskin;                // render flex skin with flat shading
   int selfcollide;                 // mode for flex self collision
-  int vertcollide;                 // mode for vertex collision
   int passive;                     // mode for passive collisions
   int activelayers;                // number of active element layers in 3D
   int group;                       // group for visualization

model/flex/poncho_edgeequality.xml

@@ -15,7 +15,7 @@
 
 <mujoco model="Poncho">
   <include file="mannequin.xml"/>
-  <option timestep="0.01" integrator="implicitfast" viscosity=".3" solver="CG" tolerance="1e-6">
+  <option timestep="0.005" integrator="implicitfast" viscosity=".3" solver="CG" tolerance="1e-6">
     <flag energy="enable"/>
   </option>
 
@@ -33,7 +33,7 @@
   <worldbody>
     <light directional="false" diffuse=".2 .2 .2" specular="0 0 0" pos="0 0 5" dir="0 0 -1"/>
 
-    <flexcomp name="f1" type="direct" rgba=".8 .2 .2 1" radius="0.02" dim="2" pos="0 0 2"
+    <flexcomp name="f1" type="direct" rgba=".8 .2 .2 1" radius="0.01" dim="2" pos="0 0 2"
               mass="1"
          point="0 0 0
                 -1 1 0
@@ -1414,8 +1414,8 @@
                 398 399 418
                 398 376 378">
       <edge equality="true" damping="0.1"/>
-      <elasticity poisson="0.3" young="3e5" thickness="8e-3" elastic2d="bend"/>
+      <elasticity poisson="0" young="3e5" thickness="8e-3" elastic2d="bend"/>
-      <contact solref="0.003" contype="0" conaffinity="0" vertcollide="true"/>
+      <contact solref="0.003"/>
     </flexcomp>
 
   </worldbody>

python/mujoco/introspect/structs.py

@@ -8119,11 +8119,6 @@ STRUCTS: Mapping[str, StructDecl] = dict([
                  type=ValueType(name='int'),
                  doc='mode for flex self collision',
              ),
-             StructFieldDecl(
-                 name='vertcollide',
-                 type=ValueType(name='int'),
-                 doc='mode for vertex collision',
-             ),
              StructFieldDecl(
                  name='passive',
                  type=ValueType(name='int'),

src/experimental/platform/gui_spec.cc

@@ -537,7 +537,6 @@ void ElementSpecGui(mjsElement* element, SpecEditor* editor) {
       FIELD(internal, "enable internal collisions");
       FIELD(flatskin, "render flex skin with flat shading");
       FIELD(selfcollide, "mode for flex self collision");
-      FIELD(vertcollide, "mode for vertex collision");
       FIELD(passive, "mode for passive collisions");
       FIELD(activelayers, "number of active element layers in 3D");
       FIELD(group, "group for visualization");

src/user/user_flexcomp.cc

@@ -502,14 +502,6 @@ bool mjCFlexcomp::Make(mjsBody* body, char* error, int error_sz, const mjVFS* vf
       // add new body at vertex coordinates
       mjsBody* pb = mjs_addBody(body, 0);
 
-      // add geom if vertcollide
-      if (dflex->vertcollide) {
-        mjsGeom* geom = mjs_addGeom(pb, 0);
-        geom->type = mjGEOM_SPHERE;
-        geom->size[0] = dflex->radius;
-        geom->group = 4;
-      }
-
       // set frame and inertial
       pb->pos[0] = point[3*i];
       pb->pos[1] = point[3*i+1];
@@ -605,13 +597,6 @@ bool mjCFlexcomp::Make(mjsBody* body, char* error, int error_sz, const mjVFS* vf
           pb->inertia[2] = pb->mass*(2.0*inertiabox*inertiabox)/3.0;
           pb->explicitinertial = true;
 
-          // add geom if vertcollide
-          if (dflex->vertcollide) {
-            mjsGeom* geom = mjs_addGeom(pb, 0);
-            geom->type = mjGEOM_SPHERE;
-            geom->size[0] = dflex->radius;
-          }
-
           for (int d=0; d < 3; d++) {
             mjsJoint* jnt = mjs_addJoint(pb, 0);
             jnt->type = mjJNT_SLIDE;

src/xml/xml_native_reader.cc

@@ -318,7 +318,7 @@ std::vector<const char*> MJCF[nMJCF] = {
             {"elasticity", "?", "young", "poisson", "damping", "thickness", "elastic2d"},
             {"contact", "?",  "contype", "conaffinity", "condim", "priority",
                 "friction", "solmix", "solref", "solimp", "margin", "gap",
-                "internal", "selfcollide", "activelayers", "vertcollide", "passive"},
+                "internal", "selfcollide", "activelayers", "passive"},
             {"pin", "*", "id", "range", "grid", "gridrange"},
             {"plugin", "*", "plugin", "instance"},
             {"<"},
@@ -334,7 +334,7 @@ std::vector<const char*> MJCF[nMJCF] = {
         {"<"},
             {"contact", "?",  "contype", "conaffinity", "condim", "priority",
                 "friction", "solmix", "solref", "solimp", "margin", "gap",
-                "internal", "selfcollide", "activelayers", "vertcollide", "passive"},
+                "internal", "selfcollide", "activelayers", "passive"},
             {"edge", "?", "stiffness", "damping"},
             {"elasticity", "?", "young", "poisson", "damping", "thickness", "elastic2d"},
         {">"},
@@ -1519,9 +1519,6 @@ void mjXReader::OneFlex(XMLElement* elem, mjsFlex* flex) {
       flex->internal = (n == 1);
     }
     MapValue(cont, "selfcollide", &flex->selfcollide, flexself_map, 5);
-    if (MapValue(cont, "vertcollide", &flex->vertcollide, bool_map, 2)) {
-      flex->vertcollide = (n == 1);
-    }
     if (MapValue(cont, "passive", &flex->passive, bool_map, 2)) {
       flex->passive = (n == 1);
     }
@@ -2822,9 +2819,6 @@ void mjXReader::OneFlexcomp(XMLElement* elem, mjsBody* body, const mjVFS* vfs) {
       dflex.internal = (n == 1);
     }
     MapValue(cont, "selfcollide", &dflex.selfcollide, flexself_map, 5);
-    if (MapValue(cont, "vertcollide", &n, bool_map, 2)) {
-      dflex.vertcollide = (n == 1);
-    }
     if (MapValue(cont, "passive", &n, bool_map, 2)) {
       dflex.passive = (n == 1);
     }

wasm/codegen/generated/bindings.cc

@@ -2375,12 +2375,6 @@ struct MjsFlex {
   void set_selfcollide(int value) {
     ptr_->selfcollide = value;
   }
-  int vertcollide() const {
-    return ptr_->vertcollide;
-  }
-  void set_vertcollide(int value) {
-    ptr_->vertcollide = value;
-  }
   int passive() const {
     return ptr_->passive;
   }
@@ -12554,7 +12548,6 @@ EMSCRIPTEN_BINDINGS(mujoco_bindings) {
     .property("thickness", &MjsFlex::thickness, &MjsFlex::set_thickness, reference())
     .property("vert", &MjsFlex::vert, reference())
     .property("vertbody", &MjsFlex::vertbody, reference())
-    .property("vertcollide", &MjsFlex::vertcollide, &MjsFlex::set_vertcollide, reference())
     .property("young", &MjsFlex::young, &MjsFlex::set_young, reference());
   emscripten::class_<MjsFrame>("MjsFrame")
     .property("alt", &MjsFrame::alt, reference())