DS =\
-dsco NAME="Example of single folded axis in street naming, Manila South Cemetery." \
-dsco DESCRIPTION="See $(subst $(HOME)/,https://www.,$(PWD))"
## Author: Dan Jacobson https://www.jidanni.org/
## Copyright: https://www.gnu.org/licenses/gpl.html
## Created: 2025-07-04T22:25:17+0000
## Last-Updated: 2025-07-05T11:26:02+0000
##     Update #: 72
P=smc
v=viking
$P.vik:
# Ground control points. "X","Y",lat,lon:
G:=$G B M 14.568237 121.018253
G:=$G B Q 14.566825 121.021997
G:=$G J O 14.563790 121.018703
see_gcps:$P.kml; $v $<
%.csv:%.optfile; perl -anwle 'printf "%s,%s,%s/%s\n", @F[3,4,1,2];' $< > $@
$P.kml:$P.csv; ogr2ogr -f LIBKML $@ $< -oo X_POSSIBLE_NAMES=field_1 \
        -oo Y_POSSIBLE_NAMES=field_2 -sql 'SELECT field_3 AS Name FROM "$(basename $<)"'
$P.optfile:Makefile; echo $G|xargs --max-args 4|perl -anwe \
	'print join " ","-gcp", map((ord)-64, @F[0,1]), @F[3,2]; print $$/;' > $@
# Drape contours over the wedge. Our own version of "gdal_create
# -outsize 2 2". (Makes four points per line, we actually only want
# the middle two, but will get clipped or {-simplify}ed anyway.):
K=gdal_contour -q -a Name $< $@ -lco GEOMETRY=AS_WKT
%.csv:%.xyz; $K -i 1
%.single_axis.csv:%.xyz; $K -fl 1 #1=A
#oops, rotated:
W=0
E=10
S=0
N=17
$P.%.xyz:Makefile
	perl -wle "for([$W,$N],[$E,$N],[$W,$S],[$E,$S]){print qq(@\$$_ @\$$_[$*])}" > $@
$P.%0.kml:$P.%.csv $P.optfile Makefile
	ogr2ogr -f LIBKML $@ $< --optfile $P.optfile -clipsrc 2 13 10 17 -sql \
	'SELECT Name FROM "$(basename $<)"'
$P.%.single_axis0.kml:$P.%.single_axis.csv $P.optfile
	ogr2ogr -f LIBKML $@ $< --optfile $P.optfile -clipsrc 1 1 13 18 -sql \
	'SELECT Name FROM "$(basename $<)"' -simplify 999999
%.kml:%0.kml; perl -wlpe 's!(<name>)(\d+)(</name>)!$$1 . (chr($$2+64)) . $$3!e;' $< > $@
sak=$P.0.single_axis.kml $P.1.single_axis.kml
single_axis:$(sak); $v $^
%.kmz: %.1.kml %.0.kml %.0.single_axis.kml %.1.single_axis.kml
	ogrmerge -f LIBKML -overwrite_ds -o $@ $^ $(DS)
.SECONDARY:
.PRECIOUS: %.kmz
%.vik:%.kmz; viking $< && sleep 11111
clean:; rm *.xyz *.km? *.csv *.optfile
# P.S., we notice the Cemetery is laid out on 290 deg azimuth.