YASim performance optimization

[flightgear.git] / src / FDM / UIUCModel / uiuc_getwind.cpp

diff --git a/src/FDM/UIUCModel/uiuc_getwind.cpp b/src/FDM/UIUCModel/uiuc_getwind.cpp
index 802a90d38f090e9b0c2b1b85d6817f812da07c45..35628407b85b976b9ec471f43554d8f51382500d 100644 (file)
--- a/src/FDM/UIUCModel/uiuc_getwind.cpp
+++ b/src/FDM/UIUCModel/uiuc_getwind.cpp
@@ -100,9 +100,12 @@ void uiuc_getwind()
        /* Get wind vector */
        double windmag = 0; //Wind magnitude
        double a = 0; //Parabola: Altitude = a*windmag^2 + zoff
+        double x = pow(uref,2.);
        
-       a = zref/pow(uref,2.);
-       if (Altitude >= zoff)
+        if (x) {
+           a = zref/x;
+        }
+       if ((Altitude >= zoff) && (a > 0))
                windmag = sqrt(Altitude/a);
        else
                windmag = 0.;