TopMenu/Water: Fixed hydrax crashing on nd start

still very glitchy though, and crashes upon return to main menu (during rendering - invalid pointer to listener)

Author: ohlidalp

source/main/gfx/HydraxWater.cpp

@@ -42,23 +42,38 @@ HydraxWater::HydraxWater(float water_height, Ogre::TerrainGroup* terrain_grp, Og
     , waterHeight(water_height)
     , waveHeight(water_height)
     , CurrentConfigFile(conf_file)
+    , mTerrainGroup(terrain_grp)
 {
     App::GetCameraManager()->GetCamera()->setNearClipDistance(0.1f);
 
     InitHydrax();
 
     //Apply depth technique to the terrain
-    TerrainGroup::TerrainIterator ti = terrain_grp->getTerrainIterator();
+    TerrainGroup::TerrainIterator ti = mTerrainGroup->getTerrainIterator();
     while (ti.hasMoreElements())
     {
+        // getNext() advances the iterator
         Ogre::Terrain* t = ti.getNext()->instance;
-        MaterialPtr ptr = t->getMaterial();
-        mHydrax->getMaterialManager()->addDepthTechnique(ptr->createTechnique());
+        MaterialPtr tMat = t->getMaterial();
+        mHydrax->getMaterialManager()->addDepthTechnique(tMat->createTechnique());
     }
 }
 
 HydraxWater::~HydraxWater()
 {
+    //Remove depth technique from the terrain
+    TerrainGroup::TerrainIterator ti = mTerrainGroup->getTerrainIterator();
+    while (ti.hasMoreElements())
+    {
+        // getNext() advances the iterator
+        Ogre::Terrain* t = ti.getNext()->instance;
+        MaterialPtr tMat = t->getMaterial();
+        for (Ogre::Technique* technique: tMat->getTechniques())
+        {
+            mHydrax->getMaterialManager()->removeDepthTechnique(technique);
+        }
+    }
+
     mHydrax->remove();
     mHydrax = nullptr;
 }

source/main/gfx/HydraxWater.h

@@ -62,6 +62,7 @@ class HydraxWater : public IWater
     Hydrax::Noise::Perlin* waternoise;
     Hydrax::Module::ProjectedGrid* mModule;
     Ogre::String CurrentConfigFile;
+    Ogre::TerrainGroup* mTerrainGroup; //!< For cleanup only
 };
 
 /// @} // addtogroup Gfx

source/main/gfx/hydrax/MaterialManager.cpp

@@ -3368,6 +3368,26 @@ namespace Hydrax
 		}
 	}
 
+	void MaterialManager::removeDepthTechnique(Ogre::Technique *Technique)
+	{
+		Ogre::Pass *DM_Technique_Pass0 = Technique->getPass(0);
+		ROR_ASSERT(DM_Technique_Pass0);
+		if (!DM_Technique_Pass0)
+		{
+			return;
+		}
+
+		if (DM_Technique_Pass0->getVertexProgramName() == _def_Depth_Shader_VP_Name)
+		{
+			DM_Technique_Pass0->setVertexProgram(""); // Remove vertex shader
+		}
+
+		if (DM_Technique_Pass0->getFragmentProgramName() == _def_Depth_Shader_FP_Name)
+		{
+			DM_Technique_Pass0->setFragmentProgram(""); // Remove fragment shader
+		}
+	}
+
 	void MaterialManager::addDepthTechnique(Ogre::Technique *Technique, const bool& AutoUpdate)
 	{
 		if (!Ogre::MaterialManager::getSingleton().resourceExists(_def_Depth_Material_Name))

source/main/gfx/hydrax/MaterialManager.h

@@ -255,6 +255,10 @@ namespace Hydrax
 			return mOptions;
 		}
 
+		/** Undo `addDepthTechnique()`
+		  */
+		void removeDepthTechnique(Ogre::Technique *Technique);
+
 		/** Add depth technique to an especified material
 		    @param Technique Technique where depth technique will be added
 			@param AutoUpdate The technique will be automatically updated when water parameters change