[comp.lang.postscript] rotate

kevin@math.lsa.umich.edu (Kevin Coombes) (10/06/89)

Since the PostScript command
	90 cos
returns a non-zero value (at least on the Apple LaserWriter), the command
	90 rotate
returns a matrix which isn't quite the same as what you'd get by
the supposedly equivalent command
	[ 0 1 -1 0 0 0 ] concat

My question is: which of these commands should be preferred, for example,
when printing a page in landscape mode? Since the rotate command is
supposed to first compute the cosine and then perform the concatenation,
shouldn't it even be more efficient to use the concat version?

Kevin Coombes
<kevin@math.lsa.umich.edu>