zxyfiles

#!/usr/bin/env bash
PROGRAM_NAME=$(basename "$0")

function usage {
    echo "Generate list of tiles per zoomlevel (only EPSG:28992)" 
    echo "usage: $PROGRAM_NAME <z>"
    echo "    - <z>: zoomlevel"
    exit 1
}

if test "$#" -lt 1; then
    usage
fi

set -eu

Z="$1"
RESOLUTIONS_RD_0=3440.640
EXTENT_RD=-285401.920,22598.080,595401.920,903401.920
TILESIZE_PIXELS=256

function get_resolution_for_z(){
    local z resolution resolution_z
    z="$1"
    resolution=$RESOLUTIONS_RD_0
    resolution_z=$(echo "$resolution*(2^-$z)" | bc -l)
    echo "$resolution_z"
}

function get_files_for_z(){
    local resolution_z z x y origin_x origin_y
    z="$1"
    resolution_z=$(get_resolution_for_z "$z")
    x=0
    while true;do
        y=0
        while true; do
            echo "${z}/${x}/${y}.pbf"
            y=$((y+1))
            # check if y coord is still within proj extent based on y
            height=$(echo "$TILESIZE_PIXELS*$y*$resolution_z" | bc -l)
            origin_y=$(echo $EXTENT_RD | cut -d "," -f4)
            end_y=$(echo $EXTENT_RD | cut -d "," -f2)
            current_y=$(echo "$origin_y-$height" | bc -l)
            if  (( $(echo "$current_y < $end_y" |bc -l) ));then
                break
            fi
        done
        x=$((x+1))
        # check if x coord is still within proj extent based on x
        width=$(echo "$TILESIZE_PIXELS*$x*$resolution_z" | bc -l)
        origin_x=$(echo $EXTENT_RD | cut -d "," -f1)
        end_x=$(echo $EXTENT_RD | cut -d "," -f3)
        current_x=$(echo "$width+$origin_x" | bc -l)
        if (( $(echo "$current_x > $end_x" |bc -l) ));then
            break
        fi
    done

}
get_files_for_z "$Z"