+ if (_at_model && (_offset_m.x() == 0.0)&&(_offset_m.z() == 0.0))
+ {
+ /* avoid optical effects (e.g. rotating sky) when "looking at" with
+ * heading offsets x==z==0 (view heading cannot change). */
+ _heading_offset_deg = 0.0;
+ }
+ else
+ _heading_offset_deg = heading_offset_deg;