--Define constant and bindings for stage ID (#2325)

* --fix bindings error (!!!)
Improperly terminated string caused a binding to be subsumed into a descriptor string.
* --provide a constant ref to the id used for the rigid stage.
* --add bindings and update tests
* --c++ test that references stage ID

examples/viewer.py

@@ -723,7 +723,7 @@ def mouse_press_event(self, event: Application.MouseEvent) -> None:
                 hit_object, ao_link = -1, -1
                 hit_info = raycast_results.hits[0]
 
-                if hit_info.object_id >= 0:
+                if hit_info.object_id > habitat_sim.stage_id:
                     # we hit an non-staged collision object
                     ro_mngr = self.sim.get_rigid_object_manager()
                     ao_mngr = self.sim.get_articulated_object_manager()

src/esp/bindings/Bindings.cpp

@@ -7,6 +7,7 @@
 #include "esp/assets/ResourceManager.h"
 #include "esp/core/Check.h"
 #include "esp/core/Configuration.h"
+#include "esp/core/Esp.h"
 #include "esp/core/RigidState.h"
 
 namespace py = pybind11;
@@ -44,6 +45,7 @@ PYBIND11_MODULE(habitat_sim_bindings, m) {
 #else
       false;
 #endif
+  m.attr("stage_id") = esp::RIGID_STAGE_ID;
 
   /* This function pointer is used by ESP_CHECK(). If it's null, it
      std::abort()s, if not, it calls it to cause a Python AssertionError */

src/esp/bindings/SimBindings.cpp

@@ -209,17 +209,16 @@ void initSimBindings(py::module& m) {
           &Simulator::getStageInitializationTemplate,
           R"(Get a copy of the StageAttributes template used to instance a scene's stage or None if it does not exist.)")
 
-      .def("build_semantic_CC_objects", &Simulator::buildSemanticCCObjects,
-           R"(Get a dictionary of the current semantic scene's connected
-          components keyed by color or id, where each value is a list of Semantic Objects
-          corresponding to an individual connected component.")
+      .def(
+          "build_semantic_CC_objects", &Simulator::buildSemanticCCObjects,
+          R"(Get a dictionary of the current semantic scene's connected components keyed by color or id,
+          where each value is a list of Semantic Objects corresponding to an individual connected component.)")
       .def(
           "build_vertex_color_map_report",
           &Simulator::buildVertexColorMapReport,
-          R"(Get a list of strings describing first each color found on vertices in the
-          semantic mesh that is not present in the loaded semantic scene descriptor file,
-          and then a list of each semantic object whose specified color is not found on
-          any vertex in the mesh.)")
+          R"(Get a list of strings describing first each color found on vertices in the semantic mesh that is
+          not present in the loaded semantic scene descriptor file, and then a list of each semantic object
+          whose specified color is not found on any vertex in the mesh.)")
 
       /* --- Kinematics and dynamics --- */
       .def(

src/esp/core/Esp.h

@@ -77,8 +77,8 @@ inline std::shared_ptr<Derived> shared_from(Derived* derived) {
 /** @brief Returned on failed creation or lookup of an ID. */
 constexpr int ID_UNDEFINED = -1;
 
-/** @brief Undefined or invalid attribute in physics property query. */
-constexpr double PHYSICS_ATTR_UNDEFINED = -1.0;
+/** @brief Object ID of the rigid stage.*/
+constexpr int RIGID_STAGE_ID = -1;
 
 static const double NO_TIME = 0.0;
 

src/esp/physics/RigidStage.cpp

@@ -9,7 +9,7 @@ namespace physics {
 
 RigidStage::RigidStage(scene::SceneNode* rigidBodyNode,
                        const assets::ResourceManager& resMgr)
-    : RigidBase(rigidBodyNode, ID_UNDEFINED, resMgr) {}
+    : RigidBase(rigidBodyNode, RIGID_STAGE_ID, resMgr) {}
 
 bool RigidStage::initialize(
     metadata::attributes::AbstractObjectAttributes::ptr initAttributes) {

src/tests/PhysicsTest.cpp

@@ -724,9 +724,10 @@ void PhysicsTest::testNumActiveContactPoints() {
     CORRADE_COMPARE(physicsManager_->getNumActiveContactPoints(), 4);
     // simple_room.glb has multiple subparts and our box is near two of them
     CORRADE_COMPARE(physicsManager_->getNumActiveOverlappingPairs(), 2);
-    CORRADE_COMPARE(
-        physicsManager_->getStepCollisionSummary(),
-        "[RigidObject, cubeSolid, id 0] vs [Stage, subpart 6], 4 points\n");
+    const std::string test_string = Cr::Utility::formatString(
+        "[RigidObject, cubeSolid, id {}] vs [Stage, subpart 6], 4 points\n",
+        (esp::RIGID_STAGE_ID + 1));
+    CORRADE_COMPARE(physicsManager_->getStepCollisionSummary(), test_string);
 
     float totalNormalForce = 0;
     for (auto& cp : allContactPoints) {
@@ -736,9 +737,9 @@ void PhysicsTest::testNumActiveContactPoints() {
       CORRADE_COMPARE_AS(
           (cp.contactNormalOnBInWS - Magnum::Vector3{0.0, 1.0, 0.0}).length(),
           1.0e-4, Cr::TestSuite::Compare::LessOrEqual);
-      // one object is the cube (0), other is the stage (-1)
-      CORRADE_COMPARE(cp.objectIdA, 0);
-      CORRADE_COMPARE(cp.objectIdB, -1);
+      // one object is the cube (id esp::RIGID_STAGE_ID + 1), other is the stage
+      CORRADE_COMPARE(cp.objectIdA, (esp::RIGID_STAGE_ID + 1));
+      CORRADE_COMPARE(cp.objectIdB, esp::RIGID_STAGE_ID);
       // accumulate the normal force
       totalNormalForce += cp.normalForce;
       // solver should keep the cube at the contact boundary (~0 penetration)

src_python/habitat_sim/__init__.py

@@ -59,6 +59,7 @@
         audio_enabled,
         built_with_bullet,
         cuda_enabled,
+        stage_id,
     )
     from habitat_sim.nav import (  # noqa: F401
         GreedyFollowerCodes,

src_python/habitat_sim/bindings/__init__.py

@@ -49,4 +49,5 @@
     audio_enabled,
     built_with_bullet,
     cuda_enabled,
+    stage_id,
 )

tests/test_physics.py

@@ -543,7 +543,8 @@ def test_raycast():
                 atol=0.07,
             )
             assert abs(raycast_results.hits[0].ray_distance - 6.831) < 0.001
-            assert raycast_results.hits[0].object_id == -1
+            # hit stage
+            assert raycast_results.hits[0].object_id == habitat_sim.stage_id
 
             # add a primitive object to the world and test a ray away from the origin
             cube_prim_handle = obj_template_mgr.get_template_handles("cube")[0]
@@ -906,7 +907,7 @@ def test_articulated_object_add_remove():
         robot = art_obj_mgr.add_articulated_object_from_urdf(filepath=robot_file)
         assert robot
         assert robot.is_alive
-        assert robot.object_id == 0  # first robot added
+        assert robot.object_id == habitat_sim.stage_id + 1  # first robot added
 
         # add a second robot
         robot2 = art_obj_mgr.add_articulated_object_from_urdf(
@@ -1859,7 +1860,7 @@ def test_rigid_constraints():
         assert robot.translation[1] < -3
 
         # hang AO from the world with P2P
-        constraint_settings_2.object_id_b = -1
+        constraint_settings_2.object_id_b = habitat_sim.stage_id
         constraint_settings_2.constraint_type = (
             habitat_sim.physics.RigidConstraintType.PointToPoint
         )
@@ -1903,7 +1904,7 @@ def test_rigid_constraints():
         assert abs(float(angle_error)) < 0.2
 
         # hang the object from its base link
-        constraint_settings_2.link_id_a = -1
+        constraint_settings_2.link_id_a = habitat_sim.stage_id
         sim.remove_rigid_constraint(constraint_id_2)
         constraint_id_2 = sim.create_rigid_constraint(constraint_settings_2)
         observations += simulate(sim, 5.0, produce_debug_video)

tests/test_simulator.py

@@ -247,7 +247,7 @@ def test_object_template_editing():
 
             # test adding a new object
             obj = rigid_obj_mgr.add_object_by_template_id(template_ids[0])
-            assert obj.object_id != -1
+            assert obj.object_id != habitat_sim.stage_id
 
             # test getting initialization templates
             stage_init_template = sim.get_stage_initialization_template()