--- /dev/null
+#include "yearline.h"
+
+int convert_date_to_height(struct date_value *dv)
+{
+ struct date_value * date = gedcom_new_date_value(dv);
+
+ if (date->date1.year_type != YEAR_SINGLE) {
+ debug("Date->OY conversion when type != YEAR_SINGLE");
+ }
+
+ if (date->date1.cal != CAL_GREGORIAN) {
+ debug("Not a gregorian calendar. Converting...");
+ date->date1.cal = CAL_GREGORIAN;
+ date->date1.year_type = YEAR_SINGLE;
+ }
+
+ if (gedcom_normalize_date(DI_FROM_SDN, date) != 0) {
+ debug("Error when normalizing date");
+ }
+
+ int year = date->date1.year;
+
+ free(date);
+
+ return year;
+}
\ No newline at end of file
--- /dev/null
+/****************************************************************************
+ * Familia Lignum - Genealogical program *
+ * Copyright (C) 2011-2012 Rafał Długołęcki <rafal@dlugolecki.net.pl> *
+ * *
+ * 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; version 2 of the License. *
+ * *
+ * 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., *
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
+ * *
+ ****************************************************************************/
+
+#ifndef _FAMILIA_MATH_YEARLINE_H
+#define _FAMILIA_MATH_YEARLINE_H
+
+#include <gedcom.h>
+
+/**
+ * @file math/yearline.h
+ * @brief Code for calculating year->position conversion.
+ *
+ */
+
+/**
+ * Return normalized year, which is used as a point value on the Y axis.
+ *
+ * This function is used as a common place for converting date years to global
+ * Y coords. If there will be a change in displaying height position, it will be
+ * changed in this function.
+ *
+ * @param dv Date for which to convert to the Y position.
+ * @return GLOBAL coordinate for Y axis for the given date.
+ */
+int convert_date_to_height(struct date_value *dv);
+
+
+
+#endif /* _FAMILIA_MATH_YEARLINE_H */