Extending {tilework}

{tilework} provides an extensible framework for:

• tile planning

• tile selection

• batch iteration

• parallelized data processing

Data flow

The framework accesses and processes data according to the following flow:

1. tileApply(x, tiles, ...) # operate across tiles

2. getTile(x, tiles, ..., get_params) # get data for tiles

   1. bounds <- tiles[...] # generate bounds info

   2. getBoundedData(x, bounds, get_params) # data extraction

Expanded roles:

• tileApply()- handles the function parallelization strategy and logic.

• getTile() - deals with any interactions between the data type and the tile indexing. Operations that should be performed before extraction of the actual data by tile bounds should happen at this level.

• getBoundedData() - performs the low-level data extraction from the data source, provided with a set of bounds information (commonly a SpatExtent or numeric of c(xmin, xmax, ymin, ymax))

Adding new data type support

{tilework} functionalities can be extended to work with other data types/backends by creating a getBoundedData() method for the data type. Optional additional steps:

• Method for tileApply() should also be added if there are pre-run validation/data collection steps needed.

• Method for getTile() should be added if there are operations that affect data/tile interactions.

See also

Other tilework extension: redispatch_tileapply,SpatRaster,freeTilePlan-method, token-class

Examples

if (FALSE) {
    # Extending for a custom data type:
    setMethod(
        "getBoundedData", signature("MyDataType", "SpatExtent"),
        function(x, bound) {
            # Your data extraction logic here
            my_extract_function(x, bound)
        }
    )
}