EntityId GetMouseEntityID()
{
  static ray_hit hit;
  float x, y, xMouse, yMouse, zMouse = 0.0f;
   
  if(!gEnv->pHardwareMouse || !gEnv->pRenderer || !gEnv->p3DEngine || !gEnv->pSystem  
                    || !gEnv->pEntitySystem || !g_pGame->GetIGameFramework())
   return 0;
   
  IActor *pClientActor = g_pGame->GetIGameFramework()->GetClientActor();
   
  if (!pClientActor)
   return 0;
   
  gEnv->pHardwareMouse->GetHardwareMouseClientPosition(&x,&y);
  y = gEnv->pRenderer->GetHeight() - y;
   
  gEnv->pRenderer->UnProjectFromScreen(x, y, 0.0f,&xMouse,&yMouse,&zMouse);
   
  static const unsigned int flags = rwi_stop_at_pierceable|rwi_colltype_any;
   
  float  fRange = gEnv->p3DEngine->GetMaxViewDistance();
  Vec3  vCamPos = gEnv->pSystem->GetViewCamera().GetPosition();
  Vec3     vDir = (Vec3(xMouse,yMouse,zMouse) - vCamPos).GetNormalizedSafe();
   
  IPhysicalEntity *pPhysicalEnt = pClientActor->GetEntity() ? pClientActor->GetEntity()->GetPhysics() : NULL;
   
  if(!pPhysicalEnt)
   return 0;
   
  if (gEnv->pPhysicalWorld &&  
          gEnv->pPhysicalWorld->RayWorldIntersection(vCamPos, vDir * fRange, ent_all, flags, &hit, 1, pPhysicalEnt))
  {
   if (gEnv->p3DEngine->RefineRayHit(&hit, vDir * fRange))
   {  
    if (IEntity *pEntity = gEnv->pEntitySystem->GetEntityFromPhysics(hit.pCollider))
    {
     return pEntity->GetId();
    }
   }  
  }  
   
  return 0;
}