Clean up internal resources on Destroy

ogre/src/OgreDistortionPass.cc

@@ -444,6 +444,21 @@ void OgreDistortionPass::Destroy()
     this->dataPtr->distortionInstance = nullptr;
     this->dataPtr->distortionCompositorListener.reset();
   }
+
+  if (!this->dataPtr->distortionMaterial.isNull())
+  {
+    Ogre::MaterialManager &matManager = Ogre::MaterialManager::getSingleton();
+    matManager.remove(this->dataPtr->distortionMaterial->getName());
+    this->dataPtr->distortionMaterial.setNull();
+  }
+
+  if (!this->dataPtr->distortionTexture.isNull())
+  {
+    auto &textureManager = Ogre::TextureManager::getSingleton();
+    textureManager.unload(this->dataPtr->distortionTexture->getName());
+    textureManager.remove(this->dataPtr->distortionTexture->getName());
+    this->dataPtr->distortionTexture.setNull();
+  }
 }
 
 //////////////////////////////////////////////////

ogre2/include/gz/rendering/ogre2/Ogre2LensFlarePass.hh

@@ -78,6 +78,9 @@ namespace gz
       public: void WorkspaceRemoved(
             Ogre::CompositorWorkspace *_workspace) override;
 
+      // Documentation inherited
+      public: virtual void Destroy() override;
+
       /// \brief Check to see if the lens flare is occluded and return a scaling
       /// factor that is proportional to the lens flare's visibility
       /// \remark Ogre2LensFlarePass::PreRender must have been called first.

ogre2/src/Ogre2LensFlarePass.cc

@@ -126,6 +126,14 @@ Ogre2LensFlarePass::Ogre2LensFlarePass() :
 //////////////////////////////////////////////////
 Ogre2LensFlarePass::~Ogre2LensFlarePass()
 {
+  this->Destroy();
+}
+
+//////////////////////////////////////////////////
+void Ogre2LensFlarePass::Destroy()
+{
+  this->dataPtr->rayQuery.reset();
+  this->dataPtr->currentCamera.reset();
 }
 
 //////////////////////////////////////////////////

ogre2/src/Ogre2Material.cc

@@ -151,7 +151,12 @@ Ogre2Material::~Ogre2Material()
 void Ogre2Material::Destroy()
 {
   if (!this->Scene()->IsInitialized())
+  {
+    // just reset the ogre pointers and return.
+    this->dataPtr->ogreSolidColorMat.reset();
+    this->dataPtr->ogreSolidColorShader.reset();
     return;
+  }
 
   if (!this->ogreDatablock)
     return;

ogre2/src/Ogre2RayQuery.cc

@@ -88,6 +88,9 @@ Ogre2RayQuery::Ogre2RayQuery()
 //////////////////////////////////////////////////
 Ogre2RayQuery::~Ogre2RayQuery()
 {
+  if (!this->Scene()->IsInitialized())
+    return;
+
   if (this->dataPtr->rayQuery)
   {
     Ogre2ScenePtr ogreScene =

ogre2/src/Ogre2SelectionBuffer.cc

@@ -144,6 +144,9 @@
 /////////////////////////////////////////////////
 Ogre2SelectionBuffer::~Ogre2SelectionBuffer()
 {
+  if (!this->dataPtr->scene || !this->dataPtr->scene->IsInitialized())
+    return;
+
   this->DeleteRTTBuffer();
 
   // remove selectionMaterial in destructor
@@ -157,7 +160,14 @@
   }
 
   // remove selection buffer camera
-  this->dataPtr->sceneMgr->destroyCamera(this->dataPtr->selectionCamera);
+  if (this->dataPtr->selectionCamera)
+  {
+    this->dataPtr->selectionCamera->removeListener(
+        this->dataPtr->materialSwitcher.get());
+    this->dataPtr->sceneMgr->destroyCamera(this->dataPtr->selectionCamera);
+    this->dataPtr->selectionCamera = nullptr;
+    this->dataPtr->materialSwitcher.reset();
+  }
 }
 
 /////////////////////////////////////////////////