started with generic collision_system (not working yet)

game/game.go

@@ -38,6 +38,7 @@ func NewGame(width, height, cellsize int, cfg *config.Config, startscene SceneNa
 	observers.NewPlayerObserver(&world)
 	observers.NewParticleObserver(&world)
 	observers.NewObstacleObserver(&world)
+	observers.NewEntityObserver(&world)
 	game.Observer = observers.NewGameObserver(&world, cfg.Startlevel, width, height, cellsize)
 
 	game.Scenes[Welcome] = NewWelcomeScene(game)

game/levels.go

@@ -41,6 +41,9 @@ func NewLevel(game *Game, cellsize int, plan *assets.RawLevel) *Level {
 
 	systemlist = append(systemlist, systems.NewCollectibleSystem(game.World))
 
+	systemlist = append(systemlist,
+		systems.NewCollisionSystem(game.World, gridcontainer))
+
 	systemlist = append(systemlist,
 		systems.NewPlayerSystem(game.World, gridcontainer))