#!/bin/bash

GDAL_TILE_PROCESSES=16
GDAL_TILE_ZOOMS=8-14
GDAL_SAMPLING_WARP=cubic
GDAL_SAMPLING_TILE=antialias

# Create virtual dataset with coordinates
gdal_translate -of VRT -a_srs EPSG:4326 -outsize 300% 300% -gcp 0.0 0.0 25.04917145 56.87334785 -gcp 43200.0 0.0 25.06340849 56.97044728 -gcp 43200.0 41844.0 25.23231268 56.95583387 -gcp 0.0 41844.0 25.20937443 56.86654541 GX825/GX_825_SK_frame_159.jpg GX_825_SK_frame_159.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "1884.0 3144.0\n1824.0 37620.0\n42384.0 38160.0\n41904.0 3120.0" | \
  gdaltransform -tps -output_xy GX_825_SK_frame_159.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  GX_825_SK_frame_159.vrt GX_825_SK_frame_159.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES GX_825_SK_frame_159.cut.vrt GX_825_SK_frame_159.xyz