Clarification about GNSS constraint usage in the code

[shizhinian]

Hello, thank you for sharing your excellent work and making the code available.

I was reading your paper and noticed that in the first stage, both the DD factor and Doppler factor are mentioned as part of the optimization. However, when I looked through the released code, it seems that these parts might be commented out or not currently active( if 0). For example, the optimizeSlidingWindowWithLandMark() function does not appear to incorporate GNSS constraints at this stage. Similarly, the Doppler factor also seems to be disabled in the second stage.

I might be misunderstanding something—could you kindly clarify whether these parts are currently implemented but hidden, or if the code differs slightly from the paper for some reason?

Looking forward to your insights. Thank you again for your contributions!