1 files changed, 144 insertions, 0 deletions
diff --git a/icons/moonshadow.pl b/icons/moonshadow.pl
new file mode 100755
index 0000000..957045a
--- /dev/null
+++ b/icons/moonshadow.pl
@@ -0,0 +1,144 @@
+#!/usr/bin/perl -w
+
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, see
+# <http://www.gnu.org/licenses/>.
+
+use Cwd;
+use Getopt::Long;
+use File::Basename;
+
+#
+# This script is used to generate the shaded cresent or
+# gibbous shapes in a moon icon.  After creating icon files
+# weather-clear-night.svg and weather-few-clouds.svg or
+# any other icon file which includes a moon image, find the path
+# that represent the inner, lighter colored outline of the moon.
+# The center and radius arguments that you pass to this script
+# should be based on the location and the radius less half the path
+# width after adjusting for the path's 'transform' attribute.
+#
+# Once you've determined that, go to the end of the layer object
+# (the following '</g>').  Add the following, adjusting 'style'
+# and 'id' attributes if desired:
+#
+#   <path
+#       sodipodi:nodetypes="ccaaac"
+#       style="opacity:0.25;fill:#000000;fill-opacity:1;stroke:#000000;stroke-width:0;stroke-miterlimit:4;stroke-linejoin:miter;stroke-opacity:1;"
+#       id="shadow"
+#       d="M __X0__,__Y0__
+#          C __X1__,__Y0__ __X2__,__Y2__ __X2__,__Y3__
+#          S __X1__,__Y4__ __X0__,__Y4__
+#          C __X6__,__Y4__ __X7__,__Y7__ __X7__,__Y3__
+#          S __X6__,__Y0__ __X0__,__Y0__
+#          z" />
+#
+# The first three points define the arc on the outside edge from the
+# the top center at <X0,Y0> through center left or right <X2,Y3> to bottom
+# center <X0,Y4>.  The final two define the Bezier curve for terminator
+# (the edge between light and dark portions of the moon's surface) from
+# <X0,Y4> through <X7,Y3> and ending back at the start.
+#
+# The string __ANGLE__ will be replaced within each generated file
+# with the three-digit angle value.
+#
+# An additional __OPACITY__ value can be included in the template.
+# This controls the shading of an object that would depend on the
+# amount of light being reflected off the moon; e.g.: a darker cloud
+# image when the moon is new and a lighter one when full.  The resulting
+# value will vary from 0.125 at the darkest to 0 for brightest
+#
+# Note that the file "*-night-180.svg" file is not generated.  The routine
+# in libmateweather that returns icon names knows to not append '-180' to the
+# return value.
+
+GetOptions("center=s"=>\$center,
+		   "radius=f"=>\$radius);
+
+# Slurp the svg template
+die "missing icon template" unless $#ARGV == 0;
+my $src = $ARGV[0];
+die "$src not found" unless -f $src;
+{
+  local ($/,undef);
+  open(T, $src) || die "can't open $src: $!";
+  $fmt=<T>;
+}
+
+# The "-c" option can be either an "x,y" value
+# or just a single numeric ("x,x")
+
+my $x;
+my $y;
+print "center=$center\n";
+if ($center =~ /^(.+)\,(.+)$/) {
+  $x = $1;
+  $y = $2;
+} elsif ($center =~ /^(.+)$/) {
+  $y = $x = $1;
+} else {
+  die "can't parse '-c': should be <n> or <n,n>\n";
+}
+
+use constant PI => atan2(1,1)*4;
+my $b = $radius * 4/3 * (sqrt(2) - 1.);
+
+my $x0=$x;
+my $x1=$x - $b;
+my $x2=$x - $radius;
+
+my $y0=$y+$radius;
+my $y2=$y + $b;
+my $y3=$y;
+my $y4=$y-$radius;
+
+$_ = $fmt;
+
+eval s/__X0__/$x0/g;
+eval s/__Y0__/$y0/g;
+eval s/__Y2__/$y2/g;
+eval s/__Y3__/$y3/g;
+eval s/__Y4__/$y4/g;
+
+my $pass1=$_;
+
+my $out = basename($src,".svg");
+for ($d=0; $d<360; $d+=10) {
+  if ($d == 180) {
+	$x1=$x+$b;
+	$x2=$x+$radius;
+	next;
+  }
+
+  my $angle = sprintf "%03d",$d;
+  my $name = sprintf "%s-%03d.svg",$out,$d;
+
+  open (D, ">$name") || die "can't open $name: $!";
+
+  my $h= cos( ($d % 180) * PI / 180.);
+  my $x6=$x+$h*$b;
+  my $x7=$x+$h*$radius;
+  my $y7=$y - $b;
+  my $opacity = (1+ cos($d * PI / 180.)) / 16.;
+  $_=$pass1;
+
+  eval s/__X1__/$x1/g;
+  eval s/__X2__/$x2/g;
+  eval s/__X6__/$x6/g;
+  eval s/__X7__/$x7/g;
+  eval s/__Y7__/$y7/g;
+  eval s/__OPACITY__/$opacity/g;
+  eval s/__ANGLE__/$angle/g;
+  print D;
+  close (D);
+}