GlutMenuItem
new GlutMenuItem(gState.currentMenu, false, value, label);
new GlutMenuItem(gState.currentMenu, true, menu-1, label);
GlutMenuItem *item;
GlutMenuItem *item;
GlutMenuItem *item, **prev;
GlutMenuItem *item = list;
GlutMenuItem *next = list->next;
GlutMenuItem::GlutMenuItem(GlutMenu *n_menu, bool n_trig, int n_value, const char *n_label)
class GlutMenuItem;
GlutMenuItem *list; // list of menu items
class GlutMenuItem {
GlutMenuItem(GlutMenu *n_menu, bool n_trig, int n_value, const char *n_label);
GlutMenuItem *next; // next menu entry on list