The FoxGUI toolkit does not work in Sabayon. It requires libGLU which is apparently related to OpenGL. I tried compiling from source which reported the following:
po -c FXGLCone.cpp -fPIC -DPIC -o .libs/FXGLCone.o
FXGLCone.cpp: In member function 'virtual void FX::FXGLCone::drawshape(FX::FXGLViewer*)':
FXGLCone.cpp:110:3: error: 'GLUquadric' was not declared in this scope
FXGLCone.cpp:110:18: error: 'quad' was not declared in this scope
FXGLCone.cpp:110:37: error: 'gluNewQuadric' was not declared in this scope
FXGLCone.cpp:111:36: error: 'GLU_FILL' was not declared in this scope
FXGLCone.cpp:111:44: error: 'gluQuadricDrawStyle' was not declared in this scope
FXGLCone.cpp:118:81: error: 'gluCylinder' was not declared in this scope
FXGLCone.cpp:119:38: error: 'GLU_INSIDE' was not declared in this scope
FXGLCone.cpp:119:48: error: 'gluQuadricOrientation' was not declared in this scope
FXGLCone.cpp:120:62: error: 'gluDisk' was not declared in this scope
FXGLCone.cpp:121:24: error: 'gluDeleteQuadric' was not declared in this scope
make[1]: *** [FXGLCone.lo] Error 1
make[1]: Leaving directory `/home/bobmc/Downloads/fox-1.6.47/src'
