#!/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 1831.7666362807659 1929.2760180995476 23.5766666 56.75 -gcp 11558.001823154056 2022.1168929110104 24.0266666 56.75 -gcp 11503.886964448495 12147.325791855204 24.0266666 56.5 -gcp 1705.897903372835 12049.940422322776 23.5766666 56.5 Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.JPG Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.vrt

# Add cutline to VRT
gdalwarp -r $GDAL_SAMPLING_WARP -tps -dstalpha -cutline_srs EPSG:4326 \
  -cutline "POLYGON(($(echo -e "1830.6631722880584 1928.2993966817498\n11559.18869644485 2018.9713423831072\n11503.484958979034 12143.993966817496\n1706.7155879671832 12048.24886877828" | \
  gdaltransform -tps -output_xy Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.vrt | \
  awk 'NR==1{first=$0} {printf "%s %s,", $1,$2} END{print " " first}')))" \
  Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.vrt Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.cut.vrt

# Generate tiles
gdal2tiles.py -r $GDAL_SAMPLING_TILE --xyz -z $GDAL_TILE_ZOOMS -x --processes=$GDAL_TILE_PROCESSES Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.cut.vrt Latvijas_topografiskas_kartes_Elgavas_apkartne__6828_A1_L30_5_02.xyz