was curious about this while looking through:
github.com/alicevision/geogram/blob/05b3ef4edf0b87b5e52ff7f93a520e0e98ab3951/src/lib/geogram/basic/quaternion.h#L67
Have tried following the dependency for: libmotif-dev → libxft-dev → libfontconfig1-dev → libfreetype6-dev → libpng-dev
where finally resolved by 'apt install libpng-dev' which removed an older installed packge, libpng16-dev and replaced with newer libpng12-dev