Assign value to raster cells based on the nearest polygon value

Question

I'm using ArcGIS Pro 3.1.2

I have a polygonal layer of agricultural fields, with three possible Ecological values (a range of 1-3). Between the polygons, there are gaps with no polygons (due to dirt roads, water reservoirs and such). I need to fill these gaps with the same values the fields have, to turn the whole thing into a gapless polygonal layer. To do this, I turned the gap area into a raster and now I want to assign each cell a value based on its nearest polygon. Any ideas on how to do this?

The next step would be to turn the raster layer back to a polygonal layer, and then merge the two polygon layers.

Answer 1

1. Convert polygon data to raster, smallest cell size that is sensible for you, use your ecological values field.

Rasterized polygons (1m resolution)

2. Run the Distance Allocation tool, your input raster being your rasterized polygons. Set output name, other parameters can be ignored. Result is this:

You don't need to merge anything as the source cell is included. Simply convert this raster back to a polygon format. Optionally smooth the polygon boundaries?