LensFlare: param for number of occlusion steps

There is a significant amount of CPU time taken
when checking for occlusions in the LensFlare
compositor listener. This exposes the number
of steps taken when checking occlusions to allow
users to attempt to speed up this process.

Signed-off-by: Steve Peters <scpeters@openrobotics.org>

gazebo/rendering/LensFlare.cc

@@ -55,6 +55,10 @@ namespace gazebo
       /// \brief Color of lens flare.
       public: ignition::math::Vector3d color
           = ignition::math::Vector3d(1.0, 1.0, 1.0);
+
+      /// \brief Number of steps to take in each direction when checking for
+      /// occlusion.
+      public: double occlusionSteps = 10;
     };
 
     //////////////////////////////////////////////////
@@ -95,6 +99,13 @@ namespace gazebo
       this->dataPtr->color = _color;
     }
 
+    //////////////////////////////////////////////////
+    void LensFlareCompositorListener::SetOcclusionSteps(
+        double _occlusionSteps)
+    {
+      this->dataPtr->occlusionSteps = _occlusionSteps;
+    }
+
     //////////////////////////////////////////////////
     void LensFlareCompositorListener::notifyMaterialRender(unsigned int _passId,
                                               Ogre::MaterialPtr &_mat)
@@ -313,7 +324,7 @@ namespace gazebo
       // work in normalized device coordinates
       // lens flare's halfSize is just an approximated value
       double halfSize = 0.05 * this->dataPtr->scale;
-      double steps = 10;
+      double steps = this->dataPtr->occlusionSteps;
       double stepSize = halfSize * 2 / steps;
       double cx = _imgPos.X();
       double cy = _imgPos.Y();
@@ -423,6 +434,8 @@ void LensFlare::SetCamera(CameraPtr _camera)
         this->dataPtr->lensFlareScale);
     this->dataPtr->lensFlareCompositorListener->SetColor(
         this->dataPtr->lensFlareColor);
+    this->dataPtr->lensFlareCompositorListener->SetOcclusionSteps(
+        this->dataPtr->lensFlareColor);
 
     this->dataPtr->lensFlareInstance =
         Ogre::CompositorManager::getSingleton().addCompositor(
@@ -463,6 +476,12 @@ void LensFlare::SetColor(const ignition::math::Vector3d &_color)
   }
 }
 
+//////////////////////////////////////////////////
+void LensFlare::SetOcclusionSteps(double _occlusionSteps)
+{
+  this->dataPtr->occlusionSteps = _occlusionSteps;
+}
+
 //////////////////////////////////////////////////
 void LensFlare::SetCompositorName(const std::string &_name)
 {

gazebo/rendering/LensFlare.hh

@@ -59,6 +59,12 @@ namespace gazebo
       /// \param[in] _color Color of lens flare
       public: void SetColor(const ignition::math::Vector3d &_color);
 
+      /// \brief Set the number of steps to take in each direction when
+      /// checking for occlusions.
+      /// \param[in] _occlusionSteps number of steps to take in each direction
+      /// when checking for occlusion.
+      public: void SetOcclusionSteps(double _occlusionSteps);
+
       /// \brief Callback that OGRE will invoke for us on each render call
       /// \param[in] _passID OGRE material pass ID.
       /// \param[in] _mat Pointer to OGRE material.

plugins/LensFlareSensorPlugin.cc

@@ -40,6 +40,9 @@ namespace gazebo
     public: ignition::math::Vector3d color
         = ignition::math::Vector3d(1.4, 1.2, 1.0);
 
+    /// \brief Lens flare occlusion steps
+    public: double occlusionSteps = 10;
+
     /// \brief Lens flare compositor name
     public: std::string compositorName;
   };
@@ -87,6 +90,11 @@ void LensFlareSensorPlugin::Load(sensors::SensorPtr _sensor,
     this->dataPtr->color = _sdf->Get<ignition::math::Vector3d>("color");
   }
 
+  if (_sdf->HasElement("occlusion_steps"))
+  {
+    this->dataPtr->occlusionSteps = _sdf->Get<double>("occlusion_steps");
+  }
+
   const std::string compositorName = "compositor";
   if (_sdf->HasElement(compositorName))
   {
@@ -141,6 +149,17 @@ void LensFlareSensorPlugin::SetColor(const ignition::math::Vector3d &_color)
   }
 }
 
+/////////////////////////////////////////////////
+void LensFlareSensorPlugin::SetOcclusionSteps(double _occlusionSteps)
+{
+  this->dataPtr->occlusionSteps = _occlusionSteps;
+
+  for (auto flare : this->dataPtr->lensFlares)
+  {
+    flare->SetOcclusionSteps(occlusionSteps);
+  }
+}
+
 /////////////////////////////////////////////////
 void LensFlareSensorPlugin::AddLensFlare(rendering::CameraPtr _camera)
 {
@@ -156,5 +175,6 @@ void LensFlareSensorPlugin::AddLensFlare(rendering::CameraPtr _camera)
   lensFlare->SetCamera(_camera);
   lensFlare->SetScale(this->dataPtr->scale);
   lensFlare->SetColor(this->dataPtr->color);
+  lensFlare->SetOcclusionSteps(this->dataPtr->occlusionSteps);
   this->dataPtr->lensFlares.push_back(lensFlare);
 }