Add more link APIs, with tutorial (gazebosim#375)

Signed-off-by: Louise Poubel <[email protected]>
Signed-off-by: Guillaume Doisy <[email protected]>

include/ignition/gazebo/Link.hh

@@ -20,6 +20,7 @@
 #include <memory>
 #include <optional>
 #include <string>
+#include <vector>
 
 #include <ignition/math/Pose3.hh>
 #include <ignition/math/Quaternion.hh>
@@ -114,6 +115,56 @@ namespace ignition
       public: std::optional<Model> ParentModel(
           const EntityComponentManager &_ecm) const;
 
+      /// \brief Check if this is the canonical link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return True if it is the canonical link.
+      public: bool IsCanonical(const EntityComponentManager &_ecm) const;
+
+      /// \brief Get whether this link has wind enabled.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return True if wind mode is on.
+      public: bool WindMode(const EntityComponentManager &_ecm) const;
+
+      /// \brief Get the ID of a collision entity which is an immediate child of
+      /// this link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \param[in] _name Collision name.
+      /// \return Collision entity.
+      public: gazebo::Entity CollisionByName(const EntityComponentManager &_ecm,
+          const std::string &_name) const;
+
+      /// \brief Get the ID of a visual entity which is an immediate child of
+      /// this link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \param[in] _name Visual name.
+      /// \return Visual entity.
+      public: gazebo::Entity VisualByName(const EntityComponentManager &_ecm,
+          const std::string &_name) const;
+
+      /// \brief Get all collisions which are immediate children of this link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return All collisions in this link.
+      public: std::vector<gazebo::Entity> Collisions(
+          const EntityComponentManager &_ecm) const;
+
+      /// \brief Get all visuals which are immediate children of this link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return All visuals in this link.
+      public: std::vector<gazebo::Entity> Visuals(
+          const EntityComponentManager &_ecm) const;
+
+      /// \brief Get the number of collisions which are immediate children of
+      /// this link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return Number of collisions in this link.
+      public: uint64_t CollisionCount(const EntityComponentManager &_ecm) const;
+
+      /// \brief Get the number of visuals which are immediate children of this
+      /// link.
+      /// \param[in] _ecm Entity-component manager.
+      /// \return Number of visuals in this link.
+      public: uint64_t VisualCount(const EntityComponentManager &_ecm) const;
+
       /// \brief Get the pose of the link frame in the world coordinate frame.
       /// \param[in] _ecm Entity-component manager.
       /// \return Absolute Pose of the link or nullopt if the entity does not

include/ignition/gazebo/Model.hh

@@ -98,12 +98,6 @@ namespace ignition
       /// \return Model's name.
       public: std::string Name(const EntityComponentManager &_ecm) const;
 
-      /// \brief Get the ID of the entity which is the immediate parent of this
-      /// model.
-      /// \param[in] _ecm Entity-component manager.
-      /// \return Parent entity ID.
-      public: gazebo::Entity Parent(const EntityComponentManager &_ecm) const;
-
       /// \brief Get whether this model is static.
       /// \param[in] _ecm Entity-component manager.
       /// \return True if static.

src/Link.cc

@@ -18,6 +18,8 @@
 #include <ignition/msgs/Utility.hh>
 
 #include "ignition/gazebo/components/AngularVelocity.hh"
+#include "ignition/gazebo/components/CanonicalLink.hh"
+#include "ignition/gazebo/components/Collision.hh"
 #include "ignition/gazebo/components/ExternalWorldWrenchCmd.hh"
 #include "ignition/gazebo/components/Inertial.hh"
 #include "ignition/gazebo/components/Joint.hh"
@@ -28,6 +30,8 @@
 #include "ignition/gazebo/components/Name.hh"
 #include "ignition/gazebo/components/ParentEntity.hh"
 #include "ignition/gazebo/components/Pose.hh"
+#include "ignition/gazebo/components/Visual.hh"
+#include "ignition/gazebo/components/WindMode.hh"
 
 #include "ignition/gazebo/Link.hh"
 
@@ -108,6 +112,71 @@ std::optional<Model> Link::ParentModel(const EntityComponentManager &_ecm) const
   return std::optional<Model>(parent->Data());
 }
 
+//////////////////////////////////////////////////
+Entity Link::CollisionByName(const EntityComponentManager &_ecm,
+    const std::string &_name) const
+{
+  return _ecm.EntityByComponents(
+      components::ParentEntity(this->dataPtr->id),
+      components::Name(_name),
+      components::Collision());
+}
+
+//////////////////////////////////////////////////
+Entity Link::VisualByName(const EntityComponentManager &_ecm,
+    const std::string &_name) const
+{
+  return _ecm.EntityByComponents(
+      components::ParentEntity(this->dataPtr->id),
+      components::Name(_name),
+      components::Visual());
+}
+
+//////////////////////////////////////////////////
+std::vector<Entity> Link::Collisions(const EntityComponentManager &_ecm) const
+{
+  return _ecm.EntitiesByComponents(
+      components::ParentEntity(this->dataPtr->id),
+      components::Collision());
+}
+
+//////////////////////////////////////////////////
+std::vector<Entity> Link::Visuals(const EntityComponentManager &_ecm) const
+{
+  return _ecm.EntitiesByComponents(
+      components::ParentEntity(this->dataPtr->id),
+      components::Visual());
+}
+
+//////////////////////////////////////////////////
+uint64_t Link::CollisionCount(const EntityComponentManager &_ecm) const
+{
+  return this->Collisions(_ecm).size();
+}
+
+//////////////////////////////////////////////////
+uint64_t Link::VisualCount(const EntityComponentManager &_ecm) const
+{
+  return this->Visuals(_ecm).size();
+}
+
+//////////////////////////////////////////////////
+bool Link::IsCanonical(const EntityComponentManager &_ecm) const
+{
+  auto comp = _ecm.Component<components::CanonicalLink>(this->dataPtr->id);
+  return comp != nullptr;
+}
+
+//////////////////////////////////////////////////
+bool Link::WindMode(const EntityComponentManager &_ecm) const
+{
+  auto comp = _ecm.Component<components::WindMode>(this->dataPtr->id);
+  if (comp)
+    return comp->Data();
+
+  return false;
+}
+
 //////////////////////////////////////////////////
 std::optional<math::Pose3d> Link::WorldPose(
     const EntityComponentManager &_ecm) const

src/Model.cc

@@ -86,16 +86,6 @@ std::string Model::Name(const EntityComponentManager &_ecm) const
   return "";
 }
 
-//////////////////////////////////////////////////
-Entity Model::Parent(const EntityComponentManager &_ecm) const
-{
-  auto comp = _ecm.Component<components::ParentEntity>(this->dataPtr->id);
-  if (comp)
-    return comp->Data();
-
-  return kNullEntity;
-}
-
 //////////////////////////////////////////////////
 bool Model::Static(const EntityComponentManager &_ecm) const
 {

test/integration/link.cc

@@ -20,6 +20,8 @@
 #include <ignition/common/Console.hh>
 
 #include <ignition/gazebo/components/AngularVelocity.hh>
+#include <ignition/gazebo/components/CanonicalLink.hh>
+#include <ignition/gazebo/components/Collision.hh>
 #include <ignition/gazebo/components/Inertial.hh>
 #include <ignition/gazebo/components/Joint.hh>
 #include <ignition/gazebo/components/LinearAcceleration.hh>
@@ -29,6 +31,7 @@
 #include <ignition/gazebo/components/Name.hh>
 #include <ignition/gazebo/components/ParentEntity.hh>
 #include <ignition/gazebo/components/Pose.hh>
+#include <ignition/gazebo/components/Visual.hh>
 
 #include <ignition/gazebo/EntityComponentManager.hh>
 #include <ignition/gazebo/SdfEntityCreator.hh>
@@ -135,6 +138,72 @@ TEST_F(LinkIntegrationTest, ParentModel)
   EXPECT_EQ(eModel, parentModel->Entity());
 }
 
+//////////////////////////////////////////////////
+TEST_F(LinkIntegrationTest, VisualByName)
+{
+  EntityComponentManager ecm;
+
+  // Link
+  auto eLink = ecm.CreateEntity();
+  Link link(eLink);
+  EXPECT_EQ(eLink, link.Entity());
+  EXPECT_EQ(0u, link.VisualCount(ecm));
+
+  // Visual
+  auto eVisual = ecm.CreateEntity();
+  ecm.CreateComponent<components::Visual>(eVisual, components::Visual());
+  ecm.CreateComponent<components::ParentEntity>(eVisual,
+      components::ParentEntity(eLink));
+  ecm.CreateComponent<components::Name>(eVisual,
+      components::Name("visual_name"));
+
+  // Check link
+  EXPECT_EQ(eVisual, link.VisualByName(ecm, "visual_name"));
+  EXPECT_EQ(1u, link.VisualCount(ecm));
+}
+
+//////////////////////////////////////////////////
+TEST_F(LinkIntegrationTest, CollisionByName)
+{
+  EntityComponentManager ecm;
+
+  // Link
+  auto eLink = ecm.CreateEntity();
+  Link link(eLink);
+  EXPECT_EQ(eLink, link.Entity());
+  EXPECT_EQ(0u, link.CollisionCount(ecm));
+
+  // Collision
+  auto eCollision = ecm.CreateEntity();
+  ecm.CreateComponent<components::Collision>(eCollision,
+      components::Collision());
+  ecm.CreateComponent<components::ParentEntity>(eCollision,
+      components::ParentEntity(eLink));
+  ecm.CreateComponent<components::Name>(eCollision,
+      components::Name("collision_name"));
+
+  // Check link
+  EXPECT_EQ(eCollision, link.CollisionByName(ecm, "collision_name"));
+  EXPECT_EQ(1u, link.CollisionCount(ecm));
+}
+
+//////////////////////////////////////////////////
+TEST_F(LinkIntegrationTest, IsCanonical)
+{
+  EntityComponentManager ecm;
+
+  auto id = ecm.CreateEntity();
+  ecm.CreateComponent<components::Link>(id, components::Link());
+
+  Link link(id);
+
+  EXPECT_FALSE(link.IsCanonical(ecm));
+
+  ecm.CreateComponent<components::CanonicalLink>(id,
+      components::CanonicalLink());
+  EXPECT_TRUE(link.IsCanonical(ecm));
+}
+
 //////////////////////////////////////////////////
 TEST_F(LinkIntegrationTest, LinkPoses)
 {

test/integration/model.cc

@@ -90,25 +90,6 @@ TEST_F(ModelIntegrationTest, Name)
   EXPECT_EQ("model_name", model.Name(ecm));
 }
 
-//////////////////////////////////////////////////
-TEST_F(ModelIntegrationTest, Parent)
-{
-  EntityComponentManager ecm;
-
-  auto id = ecm.CreateEntity();
-  ecm.CreateComponent<components::Model>(id, components::Model());
-
-  Model model(id);
-
-  // No parent
-  EXPECT_EQ(kNullEntity, model.Parent(ecm));
-
-  // Add parent
-  ecm.CreateComponent<components::ParentEntity>(id,
-      components::ParentEntity(100u));
-  EXPECT_EQ(100u, model.Parent(ecm));
-}
-
 //////////////////////////////////////////////////
 TEST_F(ModelIntegrationTest, Static)
 {