//#ifdef RAYAABB2
Vector3f rayFrom = Stack.alloc(raySource);
Vector3f rayDirection = Stack.alloc(Vector3f.class);
tmp.sub(rayTarget, raySource);
rayDirection.normalize(tmp);
lambda_max = rayDirection.dot(tmp);
rayDirection.x = 1f / rayDirection.x;
rayDirection.y = 1f / rayDirection.y;
rayDirection.z = 1f / rayDirection.z;
// boolean sign_x = rayDirection.x < 0f;
// boolean sign_y = rayDirection.y < 0f;