only evaluate click-on-terrain on left mouse button clicks

diff --git a/src/Input/input.cxx b/src/Input/input.cxx
index 8a49324b1a903b5e091184d36d83819ef0a13f2e..925e5c21e53e357ec0359526baf54b9b9b2d2d81 100644 (file)
--- a/src/Input/input.cxx
+++ b/src/Input/input.cxx
@@ -319,7 +319,7 @@ FGInput::doMouseClick (int b, int updown, int x, int y)
       // and be happy.
       FGScenery* scenery = globals->get_scenery();
       sgdVec3 start, dir, hit;
-      if (updown == MOUSE_BUTTON_DOWN && FGRenderer::getPickInfo(start, dir, x, y)
+      if (!b && updown == MOUSE_BUTTON_DOWN && FGRenderer::getPickInfo(start, dir, x, y)
           && scenery->get_cart_ground_intersection(start, dir, hit)) {
 
         Point3D geod = sgCartToGeod(Point3D(hit[0], hit[1], hit[2]));