From 682a1a12fbb1373efdcd459bb0b034dde821c6f5 Mon Sep 17 00:00:00 2001
From: Pedro Maciel <Pedro.Maciel@ecmwf.int>
Date: Fri, 11 Aug 2023 12:01:43 +0100
Subject: [PATCH] eckit::geometry

---
 src/eckit/geometry/CMakeLists.txt      |  1 +
 src/eckit/geometry/Ordering.h          | 50 ++++++++++++++++++++++++++
 src/eckit/geometry/iterator/Regular.cc | 35 ------------------
 3 files changed, 51 insertions(+), 35 deletions(-)
 create mode 100644 src/eckit/geometry/Ordering.h

diff --git a/src/eckit/geometry/CMakeLists.txt b/src/eckit/geometry/CMakeLists.txt
index 88dc23ff5..8c1db1045 100644
--- a/src/eckit/geometry/CMakeLists.txt
+++ b/src/eckit/geometry/CMakeLists.txt
@@ -19,6 +19,7 @@ list( APPEND eckit_geometry_srcs
     Iterator.h
     KPoint.cc
     KPoint.h
+    Ordering.h
     Point.cc
     Point.h
     Point2.cc
diff --git a/src/eckit/geometry/Ordering.h b/src/eckit/geometry/Ordering.h
new file mode 100644
index 000000000..7ee940ae0
--- /dev/null
+++ b/src/eckit/geometry/Ordering.h
@@ -0,0 +1,50 @@
+/*
+ * (C) Copyright 1996- ECMWF.
+ *
+ * This software is licensed under the terms of the Apache Licence Version 2.0
+ * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * In applying this licence, ECMWF does not waive the privileges and immunities
+ * granted to it by virtue of its status as an intergovernmental organisation nor
+ * does it submit to any jurisdiction.
+ */
+
+
+#pragma once
+
+
+namespace eckit::geometry {
+
+
+enum Ordering
+{
+    scan_full_i_full_j_i_positively_j_negatively_j_consecutive_i_single_direction,
+    scan_full_i_full_j_i_negatively_j_negatively_j_consecutive_i_single_direction,
+    scan_full_i_full_j_i_positively_j_positively_j_consecutive_i_single_direction,
+    scan_full_i_full_j_i_negatively_j_positively_j_consecutive_i_single_direction,
+    scan_full_i_full_j_i_positively_j_negatively_i_consecutive_i_single_direction,
+    scan_full_i_full_j_i_negatively_j_negatively_i_consecutive_i_single_direction,
+    scan_full_i_full_j_i_positively_j_positively_i_consecutive_i_single_direction,
+    scan_full_i_full_j_i_negatively_j_positively_i_consecutive_i_single_direction,
+    scan_full_i_full_j_i_positively_j_negatively_j_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_negatively_j_negatively_j_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_positively_j_positively_j_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_negatively_j_positively_j_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_positively_j_negatively_i_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_negatively_j_negatively_i_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_positively_j_positively_i_consecutive_i_alternating_direction,
+    scan_full_i_full_j_i_negatively_j_positively_i_consecutive_i_alternating_direction,
+    // TODO scan_ ... shift
+
+    scan_reduced_i_full_j_i_positively_j_negatively,
+    scan_reduced_i_full_j_i_negatively_j_negatively,
+    scan_reduced_i_full_j_i_positively_j_positively,
+    scan_reduced_i_full_j_i_negatively_j_positively,
+    // TODO scan_ ... shift
+
+    healpix_ring,
+    healpix_nested,
+};
+
+
+}  // namespace eckit::geometry
diff --git a/src/eckit/geometry/iterator/Regular.cc b/src/eckit/geometry/iterator/Regular.cc
index f110ec900..511f612d6 100644
--- a/src/eckit/geometry/iterator/Regular.cc
+++ b/src/eckit/geometry/iterator/Regular.cc
@@ -18,41 +18,6 @@
 namespace eckit::geometry::iterator {
 
 
-#if 0
-Scanning mode (grib2/tables/30/3.4.table, grib2/template.3.scanning_mode.def)
-
-bool iScansPositively
-- 1 0 Points of first row or column scan in the +i (+x) direction
-- 1 1 Points of first row or column scan in the -i (-x) direction
-
-bool jScansPositively
-- 2 0 Points of first row or column scan in the -j (-y) direction
-- 2 1 Points of first row or column scan in the +j (+y) direction
-
-bool jPointsAreConsecutive
-- 3 0 Adjacent points in i (x) direction are consecutive
-- 3 1 Adjacent points in j (y) direction is consecutive
-
-bool alternativeRowScanning
-- 4 0 All rows scan in the same direction
-- 4 1 Adjacent rows scan in the opposite direction
-
-- 5 0 Points within odd rows are not offset in i (x) direction
-- 5 1 Points within odd rows are offset by Di/2 in i (x) direction
-- 6 0 Points within even rows are not offset in i (x) direction
-- 6 1 Points within even rows are offset by Di/2 in i (x) direction
-- 7 0 Points are not offset in j (y) direction
-- 7 1 Points are offset by Dj/2 in j (y) direction
-
-- 8 0 n_i columns, n_j rows
-- 8 1 Rows have n_i points if points are not offset in i direction
-      Rows have n_i-1 points if points are offset by Di/2 in i direction
-      Columns have n_j points if points are not offset in j direction
-      Columns have n_j-1 points if points are offset by Dj/2 in j direction
-
-#endif
-
-
 Regular::Regular(size_t ni, size_t nj, double north, double west, double we, double ns) :
     ni_(ni), nj_(nj), north_(north), west_(west), we_(we), ns_(ns), i_(0), j_(0), lat_(north_), lon_(west_), count_(0), first_(true), p_(PointLonLat{0, 0}) {
     latValue_ = lat_;