A two-component rectilinearity measure

Recently several approaches for measuring the rectilinearity of shapes have been published [P.L. Rosin, J. Žunić, Measuring rectilinearity, Computer Vision and Image Understanding, 99(2) (2005) 175–188; J. Žunić, P.L. Rosin, Rectilinearity measurements for polygons, IEEE Transactions on Pattern Analysis and Machine Intelligence, 25(9) (2003) 1193–1200]. This paper generalises the R 1 and R 2 measures defined by Žunić and Rosin [J. Žunić, P.L. Rosin, Rectilinearity measurements for polygons, IEEE Transactions on Pattern Analysis and Machine Intelligence, 25(9) (2003) 1193–1200] to detect rectilinearity in two new situations: (1) the polygon has been skewed and (2) the shape contains two rectilinear components oriented differently to each other.