Changed the hud to ignore mouse clicks when not visible.
Changed the hud to ignore mouse clicks when not visible.

shengfuintel/OpenSubdiv,lookup1980/OpenSubdiv,shengfuintel/OpenSubdiv,takahito-tejima/OpenSubdiv,lookup1980/OpenSubdiv,poljere/OpenSubdiv,jcowles/OpenSubdiv,anshuarya/OpenSubdiv,takahito-tejima/OpenSubdiv-exp,takahito-tejima/OpenSubdiv-exp,jcowles/OpenSubdiv,jcowles/OpenSubdiv,anshuarya/OpenSubdiv,poljere/OpenSubdiv,takahito-tejima/OpenSubdiv-exp,nyotis/OpenSubdiv,lookup1980/OpenSubdiv,c64kernal/OpenSubdiv,nyotis/OpenSubdiv,takahito-tejima/OpenSubdiv-exp,anshuarya/OpenSubdiv,xldeveloper/OpenSubdiv,shengfuintel/OpenSubdiv,xldeveloper/OpenSubdiv,nyotis/OpenSubdiv,c64kernal/OpenSubdiv,poljere/OpenSubdiv,takahito-tejima/OpenSubdiv,xldeveloper/OpenSubdiv,takahito-tejima/OpenSubdiv,c64kernal/OpenSubdiv