Previously we used a `CellValue` class to hold the data for a cell,
and called a function to fill it whenever necessary. This is an
unnecessary complication when we have virtual generic arrays
and most data is already easily accessible that way anyway.
This patch removes `CellValue` and uses `fn::GVArray` to provide
access to data instead.
In the future, if rows have different types within a single column,
we can use a `GVArray` of `blender::Any` to interface with the drawing.
Along with that, the use of virtual arrays made it easy to do a
few other cleanups:
- Use selection domain interpolations from rB5841f8656d95
for the mesh selection filter.
- Change the row filter to only calculate for necessary indices.
Differential Revision: https://developer.blender.org/D13478
This patch adds support for filtering rows based on rules and values.
Filters will work for any attribute data source, they are a property
of the spreadsheet rather than of the attribute system. The properties
displayed in the row filter can depend on data type of the currently
visible column with that name. If the name is no longer visible, the
row filter filter is grayed out, but it will remember the value until
a column with its name is visible again.
Note: The comments in `screen.c` combined with tagging the sidebar
for redraw after the main region point to a lack of understanding
or technical debt, that is a point to improve in the future.
**Future Improvements**
* T89272: A search menu for visible columns when adding a new filter.
* T89273: Possibly a "Range" operation.
Differential Revision: https://developer.blender.org/D10959