Improve warning

src/graphics/stk_tex_manager.cpp

@@ -32,13 +32,14 @@ STKTexManager::~STKTexManager()
 STKTexture* STKTexManager::findTextureInFileSystem(const std::string& filename,
                                                    std::string* full_path)
 {
-    *full_path = file_manager->getFileSystem()->getAbsolutePath
-        (file_manager->searchTexture(filename).c_str()).c_str();
-    if (full_path->empty())
+    io::path relative_path = file_manager->searchTexture(filename).c_str();
+    if (relative_path.empty())
     {
         Log::warn("STKTexManager", "Failed to load %s.", filename.c_str());
         return NULL;
     }
+    *full_path =
+        file_manager->getFileSystem()->getAbsolutePath(relative_path).c_str();
     for (auto p : m_all_textures)
     {
         if (p.second == NULL)

src/tracks/track_object_presentation.cpp

@@ -31,7 +31,6 @@
 #include "graphics/particle_emitter.hpp"
 #include "graphics/particle_kind_manager.hpp"
 #include "graphics/stk_mesh_scene_node.hpp"
-#include "graphics/stk_texture.hpp"
 #include "graphics/stk_tex_manager.hpp"
 #include "graphics/render_info.hpp"
 #include "io/file_manager.hpp"