PrivateCubeScreen::updateGeometry (int,int) is always called like this updateGeometry (screen->vpSize ().width (), mInvert);, which means sides will never become 0, because screen->vpSize ().width () will always return a value >= 1.
PrivateCubeScre en::updateGeome try (int,int) is always called like this updateGeometry (screen->vpSize ().width (), mInvert);, which means sides will never become 0, because screen->vpSize ().width () will always return a value >= 1.