Question about depth calculation at different stages

[Mysterious-handsome-man]

Thank you for your amazing work! Your idea about the sparse view iput and depth guidance has been very inspiring to us. However, we have some questions regarding depth estimation:

（1）After 2000 iterations, is the depth of the synthesized pseudo-views estimated using the Midas model's estimate_depth function?
（2）Before 2000 iterations, how was the depth of the given sparse views obtained? Was it also estimated using the Midas model? However, referring to the figure below, I did not find the process of depth calculation. Could you please inform me how the depth of the given sparse views was obtained before synthesizing the pseudo-views?

（3）Throughout the entire 10000 iterations, was all render_depth estimated using the relevant code in diff_gaussian_rasterization? Does this mean that you added a depth attribute to diff_gaussian_rasterization based on the original 3D GS and added relative calculation method？