import java.awt.image.ImagingOpException;
import java.awt.image.RenderedImage;
import org.apache.sis.coverage.grid.GridCoverage;
import org.apache.sis.image.ImageProcessor;

public class ParallelTileComputation {
    /**
     * Demo entry point.
     *
     * @param  args  ignored.
     * @throws ImagingOpException unchecked exception thrown if an error occurred while computing a tile.
     */
    public static void main(String[] args) {
        GridCoverage coverage = ...;        // See "Resample a raster" code example.
        /*
         * Get all data from the coverage, assuming that the grid is two-dimensional.
         * If there is three or more dimensions, the null value needs to be replaced
         * by a `GridExtent` specifying the two-dimensional slice to fetch.
         */
        RenderedImage data = coverage.render(null);
        /*
         * With above `RenderedImage`, tiles are computed when first requested and cached for future uses.
         * If all tiles will be requested in the same thread, it results in a sequential tile computation.
         * For parallel computation using all available processors, we need to inform Apache SIS in advance
         * about which pixels will be requested. The `null` argument below means "all pixels in the image".
         * Don't use that null argument if the image is very big!
         */
        var processor = new ImageProcessor();
        data = processor.prefetch(data, null);
        /*
         * See for example "Get raster values at pixel coordinates" for using this image.
         */
    }
}