From fa5708850ec8b4d7d9795501d1bba7b83aa5a30b Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 22 Nov 2013 01:33:30 +0200
Subject: [PATCH] Automatically adjust the secondary_axis flag when elevations
 are changed

---
 source/libr2c2/terrain.cpp | 10 ++++++++--
 source/libr2c2/terrain.h   |  1 +
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/source/libr2c2/terrain.cpp b/source/libr2c2/terrain.cpp
index 5a31774..072a6e5 100644
--- a/source/libr2c2/terrain.cpp
+++ b/source/libr2c2/terrain.cpp
@@ -97,7 +97,7 @@ void Terrain::set_node_elevation(const NodeCoordinates &c, float elev, bool join
 				Tile &tile = tiles[x+y*width];
 				if(tile.nodes[i].elevation==ref)
 				{
-					tile.nodes[i].elevation = elev;
+					tile.set_node_elevation(i, elev);
 					signal_tile_changed.emit(x, y);
 				}
 			}
@@ -105,7 +105,7 @@ void Terrain::set_node_elevation(const NodeCoordinates &c, float elev, bool join
 	}
 	else
 	{
-		tiles[c.x+c.y*width].nodes[c.i].elevation = elev;
+		tiles[c.x+c.y*width].set_node_elevation(c.i, elev);
 		signal_tile_changed.emit(c.x, c.y);
 	}
 }
@@ -186,6 +186,12 @@ Terrain::Tile::Tile():
 	secondary_axis(false)
 { }
 
+void Terrain::Tile::set_node_elevation(unsigned i, float e)
+{
+	nodes[i].elevation = e;
+	secondary_axis = ((nodes[1].elevation+nodes[2].elevation) < (nodes[0].elevation+nodes[3].elevation));
+}
+
 void Terrain::Tile::save(list<DataFile::Statement> &st) const
 {
 	bool flat = true;
diff --git a/source/libr2c2/terrain.h b/source/libr2c2/terrain.h
index 837119e..fb3328e 100644
--- a/source/libr2c2/terrain.h
+++ b/source/libr2c2/terrain.h
@@ -69,6 +69,7 @@ public:
 
 		Tile();
 
+		void set_node_elevation(unsigned, float);
 		void save(std::list<Msp::DataFile::Statement> &) const;
 	};
 
-- 
2.43.0