1 files changed, 101 insertions, 0 deletions
diff --git a/frontend/pisa_change_unit.cc b/frontend/pisa_change_unit.cc
new file mode 100644
index 0000000..49f88b5
--- /dev/null
+++ b/frontend/pisa_change_unit.cc
@@ -0,0 +1,101 @@
+/* 
+   SANE EPSON backend
+   Copyright (C) 2001, 2005 SEIKO EPSON CORPORATION
+
+   This file is part of the `iscan' program.
+
+   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, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+   As a special exception, the copyright holders give permission
+   to link the code of this program with the esmod library and
+   distribute linked combinations including the two.  You must obey
+   the GNU General Public License in all respects for all of the
+   code used other then esmod.
+*/
+
+#include "pisa_change_unit.h"
+
+const double CM_PER_INCH = 2.54;	// exact, per definition
+
+
+double
+inches_reflect_zoom (double inch, long zoom)
+{
+  return inch * zoom / 100;
+}
+
+double
+inch2centi (double inch, long zoom)
+{
+  return (inch * CM_PER_INCH * zoom) / 100;
+}
+
+
+long
+inch2width (double inch, long resolution, long zoom, bool monochrome)
+{
+  int boundary = (monochrome ? 32 : 8);
+
+  return (inch2pixel (inch, resolution, zoom) / boundary) * boundary;
+}
+
+long
+inch2height (double inch, long resolution, long zoom)
+{
+  return inch2pixel (inch, resolution, zoom);
+}
+
+long
+inch2pixel (double inch, long resolution, long zoom)
+{
+  return (long) ((inch * resolution * zoom) / 100);
+}
+
+long
+inch2pixel (bool is_width,
+	    double inch, long resolution, long zoom)
+{
+  return (is_width
+	  ? inch2width  (inch, resolution, zoom)
+	  : inch2height (inch, resolution, zoom));
+}
+
+
+long
+centi2width (double centi, long resolution, long zoom)
+{
+  return (centi2pixel (centi, resolution, zoom) / 8) * 8;
+}
+
+long
+centi2height (double centi, long resolution, long zoom)
+{
+  return centi2pixel (centi, resolution, zoom);
+}
+
+long
+centi2pixel (double centi, long resolution, long zoom)
+{
+  return (long) ((centi * resolution * zoom) / (100 * CM_PER_INCH));
+}
+
+long
+centi2pixel (bool is_width,
+	     double centi, long resolution, long zoom)
+{
+  return (is_width
+	  ? centi2width  (centi, resolution, zoom)
+	  : centi2height (centi, resolution, zoom));
+}