#!/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 3864.0 2981.3896609227345 25.3766666 59.75 -gcp 21721.5 3066.3451917732073 26.2766666 59.75 -gcp 21933.0 33384.27598665925 26.2766666 59 -gcp 3717.0 33375.40439132851 25.3766666 59 Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.JPG Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "3861.0 2979.0\n3766.5 18183.754580788453\n3717.0 33372.001665741256\n12836.25 33399.76290949472\n21936.0 33381.0\n21820.5 18235.50666296502\n21723.0 3066.0" | \
  gdaltransform -tps -output_xy Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.vrt Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.cut.vrt Latvijas_un_Igaunijas_topografiskas_kartes_Tapa_6828_A1_L36_3_02.xyz