#!/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 2409.0 3006.0 21.776666666666667 56.75 -gcp 21954.0 3030.0 22.226666666666667 56.75 -gcp 22083.0 23211.0 22.226666666666667 56.5 -gcp 2415.0 23157.0 21.776666666666667 56.5 lvva/Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.JPG Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "2409.0 3006.0\n21954.0 3030.0\n22083.0 23211.0\n2415.0 23157.0" | \
  gdaltransform -tps -output_xy Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.vrt Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.cut.vrt Kurzemes,Vidzemes,Kaunas_un_Vitebskas_gubernas__Skrundas_apkartne__6828__A1_L22_23_02.xyz