Problem: 'Model shadows' option on Hillshade dialog box should be disabled when input is a TIN
TIN's don't support modeling of cast shadows, so even though the option is enabled, using it does nothing.
This is a known issue.
Solution or Workaround
- Convert the TIN to a raster via the 'TIN to Raster conversion' tool found on the 3D Toolbar.
- Use the resulting raster surface as input to the Hillshade dialog.