From 39472e4d817d8b2c47c9987556af1c12a45f282a Mon Sep 17 00:00:00 2001
From: ehofman <ehofman>
Date: Thu, 5 Nov 2009 13:46:15 +0000
Subject: [PATCH] Save a costly SGVec3d::fromGeod() calculation

---
 simgear/scene/sky/sky.cxx | 14 ++++++--------
 simgear/scene/sky/sky.hxx |  3 ++-
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/simgear/scene/sky/sky.cxx b/simgear/scene/sky/sky.cxx
index 2eec5cc3..21662c66 100644
--- a/simgear/scene/sky/sky.cxx
+++ b/simgear/scene/sky/sky.cxx
@@ -147,22 +147,20 @@ bool SGSky::reposition( const SGSkyState &st, const SGEphemeris& eph, double dt
     double angle = st.gst * 15;	// degrees
     double angleRad = SGMiscd::deg2rad(angle);
 
-    SGVec3f view_pos, zero_elev, view_up;
+    SGVec3f zero_elev, view_up;
     double lon, lat, alt;
 
-    view_pos = toVec3f( SGVec3d::fromGeod(st.pos) );
-    SGGeod geodZeroViewPos = SGGeod::fromGeodM(st.pos, 0);
+    SGGeod geodZeroViewPos = SGGeod::fromGeodM(st.pos_geod, 0);
     zero_elev = toVec3f( SGVec3d::fromGeod(geodZeroViewPos) );
-
     view_up = toVec3f( st.ori.backTransform(SGVec3d::e2()) );
-    lon = st.pos.getLongitudeRad();
-    lat = st.pos.getLatitudeRad();
-    alt = st.pos.getElevationM();
+    lon = st.pos_geod.getLongitudeRad();
+    lat = st.pos_geod.getLatitudeRad();
+    alt = st.pos_geod.getElevationM();
 
     dome->reposition( zero_elev, alt, lon, lat, st.spin );
 
     osg::Matrix m = osg::Matrix::rotate(angleRad, osg::Vec3(0, 0, -1));
-    m.postMultTranslate(toOsg(view_pos));
+    m.postMultTranslate(toOsg(st.pos));
     _ephTransform->setMatrix(m);
 
     double sun_ra = eph.getSunRightAscension();
diff --git a/simgear/scene/sky/sky.hxx b/simgear/scene/sky/sky.hxx
index 1f1190f8..28678041 100644
--- a/simgear/scene/sky/sky.hxx
+++ b/simgear/scene/sky/sky.hxx
@@ -57,7 +57,8 @@ using std::vector;
 
 
 typedef struct {
-        SGGeod pos;
+        SGVec3d pos;
+        SGGeod pos_geod;
         SGQuatd ori;
         double spin;
 	double gst;
-- 
2.39.5