#!/bin/bash
set -e

echo '=== REGENERATE TRI TILES WITH LOWER THRESHOLDS ==='
echo "Start: $(date)"

TMP='/tmp/tri_gen'
TERRAIN_DIR='/home/slin/enduro-trails/data/terrain'
TRI_DIR="${TERRAIN_DIR}/tri"

echo ''
echo '=== Step 1: New color ramp (lower thresholds) ==='
# TRI stats: mean=2.97, stddev=2.12, max=86.8
# Most terrain: 0-5. Interesting: 3+. Very rugged: 8+
cat > $TMP/tri_color_v2.txt << 'EOF'
nv    0    0    0    0
0     0    0    0    0
2     0    0    0    0
3     255  255  100  60
4     255  230  50   100
5     255  200  0    140
7     255  150  0    180
10    255  100  0    200
15    230  50   0    220
20    200  0    0    235
30    180  0   50    245
50    150  0   100   255
EOF

echo ''
echo '=== Step 2: Generate colored TRI ==='
gdaldem color-relief \
  $TMP/tri_raw.tif \
  $TMP/tri_color_v2.txt \
  $TMP/tri_colored_v2.tif \
  -alpha \
  -of GTiff \
  -co COMPRESS=LZW \
  -co BIGTIFF=YES 2>&1

echo 'Stats:'
gdalinfo -stats $TMP/tri_colored_v2.tif 2>&1 | grep STATISTICS_MAX

echo ''
echo '=== Step 3: Regenerate tiles ==='
rm -rf ${TRI_DIR}
mkdir -p ${TRI_DIR}

gdal2tiles.py \
  --zoom=5-12 \
  --processes=4 \
  --tilesize=256 \
  --webviewer=none \
  $TMP/tri_colored_v2.tif \
  ${TRI_DIR}/ 2>&1

echo ''
echo '=== Step 4: Stats ==='
for z in 5 6 7 8 9 10 11 12; do
  total=$(find ${TRI_DIR}/$z/ -name '*.png' 2>/dev/null | wc -l)
  nonempty=$(find ${TRI_DIR}/$z/ -name '*.png' -size +400c 2>/dev/null | wc -l)
  echo "  zoom $z: $total total, $nonempty non-empty"
done

echo ''
du -sh ${TRI_DIR}
echo '=== DONE ==='
echo "End: $(date)"