docs: private static void checkBehindCamera(SceneStructureMetric structure, SceneObservations observations, BundleAdjustment<SceneStructureMetric> bundleAdjustment) {
  
  		int totalBehind = 0;
  		Point3D_F64 X = new Point3D_F64();
  		for (int i = 0; i < structure.points.length; i++) {
  			structure.points[i].get(X);
  			if( X.z < 0 )
  				totalBehind++;
  		}
  		structure.views[1].worldToView.T.print();
  		if( totalBehind > structure.points.length/2 ) {
  			System.out.println("Flipping because it's reversed. score = "+bundleAdjustment.getFitScore());
  			for (int i = 1; i < structure.views.length; i++) {
  				Se3_F64 w2v = structure.views[i].worldToView;
  				w2v.set(w2v.invert(null));
  			}
  			triangulatePoints(structure,observations);
  
  			bundleAdjustment.setParameters(structure,observations);
  			bundleAdjustment.optimize(structure);
  			System.out.println("  after = "+bundleAdjustment.getFitScore());
  		} else {
  			System.out.println("Points not behind camera. "+totalBehind+" / "+structure.points.length);
  		}
  	}