tilemaking.sh

#!/bin/bash
# adapt these to local environment
PARALLEL=/home/minetest/building/parallel-20140822/src/parallel
MAPPER=/home/minetest/minetest/util/minetestmapper
WORLDPATH=/home/minetest/minetest/worlds/newworld/
TILEPATH=/var/www/mineguild.de/mt/leafletmap/tiles
PNGCRUSH="/home/minetest/local/bin/pngcrush -q -w 512 -brute"

#MAPSIZE*TILESIZE= max/min xy reached
MAPSIZE=8
TILESIZE=256
LEVELS=5

export MAPPER
export PNGCRUSH

export WORLDPATH
export TILEPATH
export LEVELS
export TILESIZE

#xpos ypos
rendertile (){
	geomstring=$(($1 * $TILESIZE))":"$(($2 * $TILESIZE))"+$TILESIZE+$TILESIZE"
	succ=1
	while [[ $succ == 1 ]]; do
		$MAPPER \
			--drawalpha \
			--geometry $geomstring \
			-i $WORLDPATH \
			-o $TILEPATH/$LEVELS/$1_$2.png.uncrush \
			> /dev/zero 2> /dev/zero
		succ=$?
		# database locked, better wait
		if [[ $succ == 1 ]]; then
			sleep 0.1
		fi
	done
	$PNGCRUSH $TILEPATH/$LEVELS/$1"_"$2.png.uncrush $TILEPATH/$LEVELS/$1"_"$2.png
}
export -f rendertile


#prelevel basex basey
combine_resize(){
	basex=$2
	basey=$3
	if [[ $basex == -0 ]]; then basex=0; fi
	if [[ $basey == -0 ]]; then basey=0; fi

	x=$(($basex * 2))
	y=$(($basey * 2))

	drueber=$TILEPATH/$1/$x"_"$(($y + 1)).png
	diagonal=$TILEPATH/$1/$(($x + 1))_$(($y + 1)).png
	selbst=$TILEPATH/$1/$x"_"$y.png
	rechts=$TILEPATH/$1/$(($x + 1))_$y.png

	if [[ ! -f $drueber ]]; then drueber=$TILEPATH/blank.png ; fi
	if [[ ! -f $diagonal ]]; then diagonal=$TILEPATH/blank.png ; fi
	if [[ ! -f $selbst ]]; then selbst=$TILEPATH/blank.png ; fi
	if [[ ! -f $rechts ]]; then rechts=$TILEPATH/blank.png ; fi

	montage $drueber $diagonal $selbst $rechts \
		-geometry $(($TILESIZE / 2))x$(($TILESIZE / 2))+0+0 \
		$TILEPATH/$(($1 - 1))/$basex"_"$basey.png.uncrush


	$PNGCRUSH $TILEPATH/$(($1 - 1))/$basex"_"$basey.png.uncrush $TILEPATH/$(($1 - 1))/$basex"_"$basey.png
}
export -f combine_resize

rendertiles(){
	$PARALLEL --eta \
		-j$1 \
		rendertile \
		::: $(seq -$MAPSIZE $MAPSIZE) \
		::: $(seq -$MAPSIZE $MAPSIZE)
}
make_zoomlevels(){
	div=2
	for zoom in $(seq $LEVELS -1 1); do 
		$PARALLEL --eta \
			-j$1 \
			combine_resize $zoom\
			::: $(seq -$(($(($MAPSIZE / $div)) + 1)) $(($(($MAPSIZE / $div)) + 1))) \
			::: $(seq -$(($(($MAPSIZE / $div)) + 1)) $(($(($MAPSIZE / $div)) + 1)))
		div=$(($div * 2))
		wait
	done
}

dostuf(){
	echo RENDERING TILES
	rendertiles $1
	echo COMBINING TILES
	make_zoomlevels $1
	echo WAITING FOR COMPRESSION TO FINISH
	rm $TILEPATH/[0-5]/*uncrush
}
#invoke ./filename numworkers
dostuf $1

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