Try cleaning up textures when unloading tracks. Crashes at this time, more debugging is required

src/graphics/material.cpp

@@ -521,7 +521,6 @@ void Material::install(bool is_full_path, bool complain_if_not_found)
         video::ITexture* tex = irr_driver->applyMask(m_texture, m_mask);
         if (tex)
         {
-            // TODO
             irr_driver->removeTexture(m_texture);
             m_texture = tex;
         }
@@ -537,15 +536,7 @@ void Material::install(bool is_full_path, bool complain_if_not_found)
 //-----------------------------------------------------------------------------
 Material::~Material()
 {
-    if (m_texture != NULL)
-    {
-        m_texture->drop();
-        if (m_texture->getReferenceCount() == 1)
-        {
-            irr_driver->removeTexture(m_texture);
-            m_texture = NULL;
-        }
-    }
+    unloadTexture();
 
     // If a special sfx is installed (that isn't part of stk itself), the
     // entry needs to be removed from the sfx_manager's mapping, since other
@@ -556,6 +547,22 @@ Material::~Material()
     }
 }   // ~Material
 
+//-----------------------------------------------------------------------------
+
+void Material::unloadTexture()
+{
+    if (m_texture != NULL)
+    {
+        m_texture->drop();
+        if (m_texture->getReferenceCount() == 1)
+        {
+            irr_driver->removeTexture(m_texture);
+        }
+        m_texture = NULL;
+        m_installed = false;
+    }
+}
+
 //-----------------------------------------------------------------------------
 /** Initialise the data structures for a custom sfx to be played when a
  *  kart is driving on that particular material.

src/graphics/material.hpp

@@ -283,6 +283,8 @@ public:
                    bool load_texture = true);
          ~Material ();
 
+    void unloadTexture();
+
     void  setSFXSpeed(SFXBase *sfx, float speed, bool should_be_paused) const;
     void  setMaterialProperties(video::SMaterial *m, scene::IMeshBuffer* mb);
     void  adjustForFog(scene::ISceneNode* parent, video::SMaterial *m, 

src/graphics/material_manager.cpp

@@ -383,6 +383,16 @@ void MaterialManager::makeMaterialsPermanent()
     m_shared_material_index = (int) m_materials.size();
 }   // makeMaterialsPermanent
 
+// ----------------------------------------------------------------------------
+
+void MaterialManager::unloadAllTextures()
+{
+    for (int i = 0; i < m_shared_material_index; i++)
+    {
+        m_materials[i]->unloadTexture();
+    }
+}
+
 // ----------------------------------------------------------------------------
 bool MaterialManager::hasMaterial(const std::string& fname)
 {

src/graphics/material_manager.hpp

@@ -83,6 +83,8 @@ public:
     void      makeMaterialsPermanent();
     bool      hasMaterial(const std::string& fname);
 
+    void      unloadAllTextures();
+
     Material* getLatestMaterial() { return m_materials[m_materials.size()-1]; }
 };   // MaterialManager
 

src/modes/world.cpp

@@ -28,6 +28,7 @@
 #include "graphics/camera.hpp"
 #include "graphics/irr_driver.hpp"
 #include "graphics/material.hpp"
+#include "graphics/material_manager.hpp"
 #include "graphics/render_info.hpp"
 #include "io/file_manager.hpp"
 #include "input/device_manager.hpp"
@@ -430,6 +431,7 @@ Controller* World::loadAIController(AbstractKart *kart)
 //-----------------------------------------------------------------------------
 World::~World()
 {
+    material_manager->unloadAllTextures();
     RewindManager::destroy();
 
     irr_driver->onUnloadWorld();