From 52b4508e08474163c6e3f99ff8e5aa490f4d71b9 Mon Sep 17 00:00:00 2001
From: Christian Sueltrop <christian.sueltrop@web.de>
Date: Mon, 6 May 2024 21:53:46 +0200
Subject: [PATCH] Added LUA script "passport_guide_germany.lua", which
 implements a cropping guide for passport photos according to the standards
 for German passport and ID card photos.

---
 contrib/passport_guide_germany.lua | 105 +++++++++++++++++++++++++++++
 1 file changed, 105 insertions(+)
 create mode 100644 contrib/passport_guide_germany.lua

diff --git a/contrib/passport_guide_germany.lua b/contrib/passport_guide_germany.lua
new file mode 100644
index 0000000..f020ae7
--- /dev/null
+++ b/contrib/passport_guide_germany.lua
@@ -0,0 +1,105 @@
+--[[
+  German passport photo cropping guide for darktable.
+  Derived from the passport cropping guide by Kåre Hampf.
+
+  copyright (c) 2017  Kåre Hampf
+  copyright (c) 2024  Christian Sültrop
+  
+  darktable 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 3 of the License, or
+  (at your option) any later version.
+
+  darktable 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 darktable.  If not, see <http://www.gnu.org/licenses/>.
+]]
+
+--[[
+PASSPORT CROPPING GUIDE
+Guides for cropping passport and ID card ("Personalausweis") photos based on the "Passbild-Schablone" 
+from the German Federal Ministry of the Interior and Community. 
+(https://www.bmi.bund.de/SharedDocs/downloads/DE/veroeffentlichungen/themen/moderne-verwaltung/ausweise/passbild-schablone-erwachsene.pdf?__blob=publicationFile&v=3) 
+
+INSTALLATION
+* copy this file in $CONFIGDIR/lua/ where CONFIGDIR is your darktable configuration directory
+* add the following line in the file $CONFIGDIR/luarc
+  require "passport_guide_germany"
+* (optional) add the line:
+  "plugins/darkroom/clipping/extra_aspect_ratios/passport 35x45mm=45:35"
+  to $CONFIGDIR/darktablerc
+
+USAGE
+* when using the cropping tool, select "Passport Photo Germany" as guide and if you added the line in yout rc
+  select "passport 35x45mm" as aspect
+]]
+
+local dt = require "darktable"
+local du = require "lib/dtutils"
+local gettext = dt.gettext
+
+du.check_min_api_version("2.0.0", "passport_guide_germany") 
+
+-- Tell gettext where to find the .mo file translating messages for a particular domain
+gettext.bindtextdomain("passport_guide_germany",dt.configuration.config_dir.."/lua/locale/")
+
+local function _(msgid)
+  return gettext.dgettext("passport_guide_germany", msgid)
+end
+
+dt.guides.register_guide("Passport Photo Germany",
+-- draw
+function(cairo, x, y, width, height, zoom_scale)
+  local _width, _height
+
+  -- get the max 35x45 rectangle
+  local aspect_ratio = 45 / 35
+  if width * aspect_ratio > height then
+    _width = height / aspect_ratio
+    _height = height
+  else
+    _width = width
+    _height = width * aspect_ratio
+  end
+
+  cairo:save()
+
+  cairo:translate(x + (width - _width) / 2, y + (height - _height) / 2)
+  cairo:scale(_width / 35, _height / 45)
+
+  -- the outer rectangle
+  cairo:rectangle( 0, 0, 35, 45)
+
+  -- Nose position: The nose tip must be between these lines
+  cairo:draw_line(15.5, 45, 15.5, 13)
+  cairo:draw_line(35-15.5, 45, 35-15.5, 13)
+
+  -- Face height
+  -- optimum face height: The upper end of the head should be between these lines
+  cairo:draw_line(0, 4, 35, 4)
+  cairo:draw_line(0, 8, 35, 8)
+
+  -- tolerated face height: The upper end of the head must not be below this line
+  cairo:draw_line(6, 13, 30, 13)
+
+  -- Eye area: The eyes must be between these lines
+  cairo:draw_line(0, 13, 35, 13)
+  cairo:draw_line(0, 23, 35, 23)
+
+  -- Cheek line: The cheek must lie on this line
+  cairo:draw_line(9, 45-5, 27, 45-5)
+
+  cairo:restore()
+end,
+-- gui
+function()
+  return dt.new_widget("label"){label = _("Passport Photo Germany"), halign = "start"}
+end
+)
+
+-- kate: tab-indents: off; indent-width 2; replace-tabs on; remove-trailing-space on; hl Lua;
+-- vim: shiftwidth=2 expandtab tabstop=2 cindent syntax=lua