The flood fill is a very common programming algorithm used for a variety of purposes from filling in the confined area in paint program to finding a path from A to B to expanding water outward from a single source.
This asset contains a single flood fill script with a few utility scripts used within the main script in order to set a confined area of a ds_grid to a single value but easily modifiable for other purposes and if support is required to edit this to your needs it is available.
Usage : ds_grid_flood_fill(grid, start x , start y,value)
Utility scripts included
These scripts are called from ds_grid_flood_fill but have utility usages which make accessing them from outside of the flood fill script useful.