Material Interface Filter does not work with non down converted data.
CTH Material Volume Fractions are generally converted from float or doubles that go from 0.0 to 1.0 to unsigned chars that go from 0 to 255. This way we have a huge memory savings. However, sometimes people need to stay with the floats or doubles, as they need a volume fraction that is in the lower (or upper) range, and has good precision. As an example, my user is trying to use a material volume fraction around 0.001 or significantly smaller. Anyway, the way to do this is by unchecking the "Down Convert Volume Fraction" checkbox.
The Material Interface Filter fails for these non down converted volume fractions. Here is how to test:
- Linux, master, builtin server
- Load dave's small cth dataset. Uncheck down convert volume fraction checkbox. Apply
- Material Interface Filter. The "Select Material Fraction Arrays" does not show the Material Volume Fractions. This is a bug.
Either all variables need to be available, or optionally (default off) all variables need to be available.