Fixed build system

water/water.h

@@ -26,6 +26,7 @@ class Water : public /* Ogre::FrameListener, */ Ogre::RenderTargetListener {
 	void create_cameras();
 	btGhostObject *mWaterBody;
 	Ogre::Bullet::DynamicsWorld *mDynWorld;
+	std::set<btCollisionObject *> mOverlaps;
 
 public:
 	Water();
@@ -43,5 +44,10 @@ public:
 	postRenderTargetUpdate(const Ogre::RenderTargetEvent &evt) override;
 	void add_submerged_entity(Ogre::Entity *ent);
 	void add_surface_entity(Ogre::Entity *ent);
+	bool isInWater(const btCollisionObject *body) const
+	{
+		btCollisionObject *test = const_cast<btCollisionObject *>(body);
+		return mOverlaps.find(test) != mOverlaps.end();
+	}
 };
 #endif