I am working on a project which River Morphodynamics Modelling is involved. I found that iRIC software Nays2DH could help. I tried the tutorial with given .xyz and .riv file as Elevation Data input, now I am willing to apply it on my study field. I have the .tif file from USGS as input (one of the acceptable input formats based on the user manual), however, when I was trying to create the grid, it did not work well. I have noticed that the solver is written in the Boundary Fitted General Coordination system, and I am now trying to convert my .tif file to a similar .xyz or .riv file for input. Could anyone please share some ideas regarding to the conversion from .tif to .xyz or .riv? Thank you for your kindly help.