Assigning Bathymetry

Converting a 2dm file to gr3 or between gr3 or 2dm and shapefile

Assigning depths from prioritized DEMs

These tools are used by the preprocessor but also work with functions that can be used generically and consistently with SCHISM.

stacked_dem_fill

Smoother for complex topography

Often it is necessary to incorporate inudated marshy areas where elevations are poorly sampled and contours are tortuous. The script contour_smooth.py uses minmax curvature flow (Malladi and Sethian) to impose a minimum length scale of change for contours, essentially unraveling the features that are most contorted.

Optimizing depths for volume

A mesh draped over noisy bathymetry data does not necessarily represent important moments such as volumes and vertical face areas smoothly and realistically. To better represent these facets of the geometry, we compare the volumetric quantities that come from SCHISM shape functions (which are much like a TIN) to a higher order quadrature using the DEM with bilinear interpolation. The quadrature is more accurate, and also incorporates more sample points.